/diy/ - Do It Yourself

Cut the box and jackhammer it out
Diamond disc on a circular saw is enough
It's not fast but neither is a concrete saw
Not sure why you couldn't just pour your ramp on top though, hammer drill some rebar in and call it a day

>>2460086
>Not sure why you couldn't just pour your ramp on top though, hammer drill some rebar in and call it a day
skateboard ramps need a good seam that wont crumble away, so you need to dig down into the ground to get a decently thick layer of concrete, at least 1.5in thick

what this about hammer drilling in rebar? does ryobi sell cheap hammer drill? i can chip concrete easy with a concrete saw blade and a hammer drill, ya?

picture of a shitty ramp seam thats appears to have been patched over multiple times.

ALSO

my ryobi circular woodsaw got caught lengthwise on a nail the other day. after that it started making a much louder grinding noise. any idea what that may be?

...shall i just buy a new one? $30 on sale at home depot, but the cheap-ass in me would rather get it warrantied (no reciept) from home depot if i could.

>>2460051

Rent a concrete saw, just one of the "little" hand ones. If you "rent" the blade with it, ask how much. Last time I got one (I think from Home Depot?) it was like $50 for the blade, and I could have just bought the exact same one on their own shelves for like $10 more. Don't know what that other anon is about concrete saws being slow. Unless you don't care at all about cut quality, they're much faster than anything else you could use.

I have no idea what the hell that other anon is on about regarding "hammer drilling in some rebar". That isn't a thing, unless you're trying to join new concrete to old and are drilling into the old concrete to attach rebar as an anchor for the new. Even if you were doing this, you want a rotary hammer, not a hammer drill. Hammer drills suck for drilling through concrete, and they flat-out won't work with a bit much larger than like 3/8". A rotary hammer will be, literally, 10x faster or more, depending on the size of the bit.


Get the concrete saw. Cut out the perimeter of your recess. Don't do like I did the first time I used a concrete saw; cut multiple times, maybe 1/2" or so, until you're all the way through. This is much faster, easier, and wears the blade less than trying to cut through all at once. Don't cut past the corners or the box. The blade won't cut all the way through, but you can just chip out the little bit that wasn't cut, and you won't have extra kerf at the corner that needs to be filled in afterward.

Cut a much smaller (anything between 6x6 and 12x12-ish) square in the middle of the one you just cut. Break up/remove the smaller piece, and use the hole as a starting point to go to town with a sledgehammer. If the concrete is 6" or less, an 16lb or heavier sledge will take care of it pretty quick. Chip at the corners you didn't cut all the way through to clean them up. You now have a nice spot to make your new ramp.

>>2460115
>>2460107

Also, if you don't have the concrete delivered, rent or buy a mixer. I just had to mix a few bags the other day for a condenser pad, which was an unwelcome reminder of just how slow and how much of a pain in the ass it is to mix concrete by hand.

>>2460112
>after that it started making a much louder grinding noise. any idea what that may be?

Odd that it didn't just trash the blade and keep going, but it sounds like the bearings got cracked. Could probably replace them pretty easy. The size designation should be on them if you take the saw apart.

>>2460051
rent a quicksaw
concrete is like $100 a yard premixed. Have a few people waiting for you and a plan to pour.

>>2460108
It makes more sense to have the joint be like an expansion joint than to attempt to blend the two surfaces, and the ramp can be blended with epoxy of choice to never snag wheels.

>>2460115
would i use a rotary hammer to drill holes like pic rel? can a ryobi get the job done? i have way more time than money

>>2460142
>>2460122
>pouring concrete

i have a big rock pile, endless sand and ill be buying bags of portland cement, and mixing it on the ground.
it will be me and one or two other skaters working. we will be building up the ramp slowly a few gallons of concrete at a time. we work slow enough that running a generator and concrete mixer is a pita. i usually give some random barfly an oz or three of old weed to hang out and help mix the concrete. theres a bar around the corner where i may or may not be able to charge power tools.

theres not much for fill though, to make bulk for the base of the ramp. i was thinking i may haul in tires from a tireshop and put sand in the middle and wet and pack it. any tips on this method? supposedly we can grab 13 tires at a time from the tire shop.

>>2460196
I've only built ramps out of wood and gotten concrete when remodeling. The reason you'd buy a lump sum of premixed cement is it will all harden together. One yard is a lot and it takes 3-4 people to get out and where it needs to go in time. Idk if you'd want glass reinforcement in the mix or the ideal way to float and polish concrete for a skate surface.
Cement is cheap though. Research, effort, and prep will pay off.

>>2460195

Rotary hammers come in greatly varying degrees of speed and power. For anything under 3/4", an average SDS rotary hammer will work fine. I have the cordless Ryobi one, it's decent. I've used it for holes no larger than 1/2" so far, but it does so pretty fast at that size. I also have a corded Bauer (Harbor Freight) that's somewhat more powerful and cheaper.

Again, though...I don't think you need to be drilling any holes. You don't need any rebar for this unless the soil under the concrete is very weak.

>>2460196
>it will be me and one or two other skaters working. we will be building up the ramp slowly a few gallons of concrete at a time.

I'd still seriously urge you to look for a cheap, used mixer, regardless. With the amount you need to mix, it may literally be easier to mix it at your nearby bar, dump it in buckets, and drive it back. You can sell the mixer on craigslist/facebook afterwards and get back most of what you paid for it. If you got it there in the first place, you may well get ALL of it back (even slight profit if you score a really good deal).

>i was thinking i may haul in tires from a tireshop and put sand in the middle and wet and pack it. any tips on this method?

If you have enough sand to fill the tires...why even use the tires? If you can't be arsed to make the whole thing solid concrete, just mix the sand with a small portion of portland cement and dump it where you need it. It will harden into a sort of shitty sandstone with no need for tires. Just make sure it's reasonably well-compacted before it sets.

>>2460051
I've cut concrete with a circular saw but for the same price as the blade, you can rent a concrete saw and be done in no time at all and it'll actually cut all the way through

>>2460304
>buy saw blade vs rent saw
how much does a 5.5in concrete cutting disc cost? how much does saw blade rental cost? mind you i have to tack on $30 in fuel and 3hr of labor for every round trip to town.... and of course everytime i make a trip to town, it ends up chewing up most of the day.

>>2460200
i already started builing ramps there last year and i a continuing this year. ive done lots of research... i have recieved lots of different advice and used my judgement to filter stuff out or accept ideas.... i like a lot of what you have written:

I use the rotary hammer to drill anchor holes for cinder blocks as in pic rel
>>2460195

also i remember when we chipped out the ground similar to pic rel >>2460051
we had cut out the rectangle shape, and instead of cross hatching cuts, we then drilled a bunch of small 1/2 to 1in deep holes with a rotary hammer and then bashed out the rest with a sledge hammer

>>2460209
>tire fill vs sandstone
how much prtland cement do i need to make this sandstone like mix? (1) 95lb bag per cubic yard? would it help to throw in chunks of rock and metal...and car tires?

we have a mixer, we just dont use it.... we really only end up mixing about 6bags of crete every 15 minutes.... which isnt much when you have a helper on standby

>>2460415
>how much does a 5.5in concrete cutting disc cost? how much does saw blade rental cost?

Do you have one of those little cordless circular saws? Those are the only things I can think of that use blades that size. 5.5in would be a really weird size for a diamond blade. From what little I can find, one of those would run you like $50-60. Given that you couldn't cut anywhere near all the way through with what little cut depth a blade that size offers, you'd be better off with a 7" angle grinder. 7" diamond discs are cheap, much cheaper than a specialty 5.5". You're kind of back to needing a generator again or shelling out for an expensive 7" cordless grinder, though.

Rental for a normal 14" concrete blade, last I did so, was like $60. I would have rather just bought one, since they only cost $60-80 in the first place. Again, though, you still need the saw and a way to power it, so...

>how much prtland cement do i need to make this sandstone like mix? (1) 95lb bag per cubic yard? would it help to throw in chunks of rock and metal...and car tires?

Very little. Assuming the concrete covering it is reasonably thick (say, 3" at least), it needs almost no strength, just enough to hold its shape. You could probably get away with like 3-5% cement by weight, maybe even less.

Enough metal to be decent fill would be worth taking to the scrapyard, and wouldn't help structurally, anyway. There should be nothing but a fairly minimal compressive load on the sand, which it can handle just fine on its own.

>>2460784
>Very little. Assuming the concrete covering it is reasonably thick (say, 3" at least), it needs almost no strength, just enough to hold its shape. You could probably get away with like 3-5% cement by weight, maybe even less.
how do i mix the cement into the sand without wasting a bunch of time and effort? any ideas?

>Enough metal to be decent fill would be worth taking to the scrapyard, and wouldn't help structurally,
lots of burnt appliances laying around, why wouldnt they help structurally?

I was wondering if i could pay a local demoltion/paving/concrete contractor to dump a load of concrete rubble by the skatepark. its surrounded by farmland, i imagine concrete rubble is a sought after material for all the levees and what not.

I could probably buy a concrete blade and pay someone in the neighborhood to let me use their saw?

>>2460890
>how do i mix the cement into the sand without wasting a bunch of time and effort? any ideas?

Mix the sand and cement together, dry. After the cement is incorporated, spray water slowly and gently onto it until it's good and damp, but not dripping or pooling. Not really quick or easy without a mixer, but a lot easier than mixing concrete with aggregate in it.

>lots of burnt appliances laying around, why wouldnt they help structurally?

Because the sand simply doesn't need any reinforcement. At best, adding garbage does nothing. At worst, it creates voids and slip planes in the sand that collapse later. And, if you had enough actual volume of metal to act as meaningful fill, it'd be a total waste to throw it in instead of scrapping it, when it doesn't actually do anything for you.

>I was wondering if i could pay a local demoltion/paving/concrete contractor to dump a load of concrete rubble by the skatepark

If you can find such an outfit, maybe. Broken-up concrete is absolutely used as fill material for new construction. The only problem you might have is that you don't want anywhere near the amount they want/need to get rid of, and they might not want to haul out anything less than a few tons at once. Obviously, they'll do whatever you want as long as you pay them enough, but they're not going to want to hassle with it at a rate that's a good value for you unless it just happens to be convenient.

>I could probably buy a concrete blade and pay someone in the neighborhood to let me use their saw?

If someone has one. Concrete saws aren't something even a well-rounded handyman will usually have, especially not a cordless/gas-powered one.

If you have a cordless angle grinder already (or are willing to buy one), you could probably use a diamond masonry disc on it to grind a slot as deep as you can in the concrete, and the concrete will break along the line pretty cleanly if you go at it with a sledge. Start in the middle and work toward the edges.

>>2460913
>if you had enough actual volume of metal to act as meaningful fill, it'd be a total waste to throw it in instead of scrapping it,
nearest scrap yard isnt close enough to make a pickup truck load of tin scrap at all profitable... thus there is a lot of burnt tin scrap laying around....

>The only problem you might have is that you don't want anywhere near the amount they want/need to get rid of, and they might not want to haul out anything less than a few tons at once.... oh i could use multiple truck loads... it would be very nice to have a big stockpile of fill.... how much you reckon they would charge for a 10wheeler dumptruck full or half full?

>Concrete saws aren't something even a well-rounded handyman will usually have, especially not a cordless/gas-powered one.
well i dont need a concrete saw, do i? i just need a 7in wood saw and one or three 7in cocnrete blades, ya? ... and some patience*

>If you have a cordless angle grinder already
yes, i have cordless angle grinder. 0.75 to 1.25in is plenty deep enough for a seam... angle grinder should be able to cut that yea? how much are blades? $20? do concrete blades ever explode like metal cutting discs?

>...some local skater works for a concrete company says he can have hotloads diverted to my park for $100 to the driver.... i havent spoke to him in a while though, so i would need to confirm ... fuck, i may even have lost his number

ty ty for your responses, very helpful!

>>2460913
>if you had enough actual volume of metal to act as meaningful fill, it'd be a total waste to throw it in instead of scrapping it,
nearest scrap yard isnt close enough to make a pickup truck load of tin scrap at all profitable... thus there is a lot of burnt tin scrap laying around....

>The only problem you might have is that you don't want anywhere near the amount they want/need to get rid of, and they might not want to haul out anything less than a few tons at once....
oh i could use multiple truck loads... it would be very nice to have a big stockpile of fill.... how much you reckon they would charge for a 10wheeler dumptruck full or half full?

>Concrete saws aren't something even a well-rounded handyman will usually have, especially not a cordless/gas-powered one.
well i dont need a concrete saw, do i? i just need a 7in wood saw and one or three 7in cocnrete blades, ya? ... and some patience*

>If you have a cordless angle grinder already
yes, i have cordless angle grinder. 0.75 to 1.25in is plenty deep enough for a seam... angle grinder should be able to cut that yea? how much are blades? $20? do concrete blades ever explode like metal cutting discs?

>some local skater works for a concrete company says he can have hotloads diverted to my park for $100 to the driver
....i havent spoke to him in a while though, so i would need to confirm ... fuck, i may even have lost his number

ty ty for your responses, very helpful!

>>2460051
Diamond blade on a circular saw is what i use at work to cut concrete and stone. But not a battery powered saw, it has to be a corded saw. You might need a generator if you're doing this some place with no power hookup.

You just gotta go slow and let the saw do the work. Cut it in like a grid fashion in your pic and then just chisel or jackhammer out the squares.

I'm a fellow skater and also a mason and I'm glad you are doing things the right way instead of just trying to use feather finish or whatever that garbage is to get a smooth edge. The way you're doing it will last for ages, the easy way only seems to last a few months.

>>2460209
>cheap, used mixer
100% agree with this anon. If you try mix all this by hand you're probably going to have to start finishing the bottom while you're still pouring the top, especially if you're not used to mixing concrete by hand.
You can get small mixers from harbor freight and when you're done with it just return it and say it doesn't work and get your money back.

>>2460890
>I was wondering if i could pay a local demoltion/paving/concrete contractor to dump a load of concrete rubble by the skatepark.
You'd be better off driving by construction sites and asking if they have any rubble you can take off their hands. People have to pay to get rid of that stuff so they'd probably be happy to let you take it.

>>2461205
>>2461203
i have a small four cylinder truck ill be camping out of so i dont really have room for a generator. nieghbors have generators i can use but its always a pita borrowing tools from them (gas runs, favors in return, etc) i seldom borrow generators to power shit.

sometimes i do pop off the camper shell to haul local material, but using my little truck to haul only 1000lb of fill 30miles each trip would be expensive... i think it would be way cheaper to pay someone $100-200 to drop off all the material at once instead of multiple, time consuming, small loads

>>2461201
>I'm a fellow skater and also a mason and I'm glad you are doing things the right way instead of just trying to use feather finish or whatever that garbage is to get a smooth edge. The way you're doing it will last for ages, the easy way only seems to last a few months.
i dont understand most of this but it seems like an angle grinder with a masonary cut off disc should do the trick. i think i might go by a roatry hammer drill today for drilling holes for rebar to conect cinder blocks >>2460195 pic related
>do i need a rotary hammer drill to accomplish this??
> do those cinderblocks actually need to be anchhored in??

Angle grinder w masonry disc. I have been diy building concrete skate obstacles for years. People will tell you to skip cutting the ground and use mortar or ardex on the seam, but this only works for a few days before it falls apart.
I was able to build this whole fucking thing with very few tools. Saws all for the wood, impact, hammer and chisel, hacksaw for cutting rebar, shovels, concrete float and marshaltown spring steel finisher. I'll be happy to answer any questions, I been doing this shit for years and have learned from my friends who build concrete skateparks for a living. A lot of the shit on YouTube teaches techniques that are blatantly wrong

>>2461254
You can get small generators from harbor freight but they will cost a few hundred bucks.

>>2461258
How do you plan to use the angle grinder and rotary hammer without a generator? Battery powered tools don't last for shit when you're working with concrete.

But yes, an angle grinder will work and they are a good tool to have in general.

>>2461258
Whether you need to put rebar in the blocks depends on how high the block wall will be and what it will be used for.

>>2461273
Baller. What do you use for coping?

>>2461164
>nearest scrap yard isnt close enough

Then just leave it. There's no good reason to add it, and a few to not.

>how much you reckon they would charge for a 10wheeler dumptruck full or half full?

100% dependent on how far they have to go and how bad they need to get rid of it. Concrete is something of a problematic construction waste product. It often costs more to dispose of than regular construction debris. If you get lucky and there just happens to be someone wanting to get rid of about as much as you want from a site that isn't too far away, they may deliver it to you outright free. If not, you'd have to pay for delivery, which I can't even guess on because, again, it's totally dependent on how far the driver has to go.

>7in wood saw and one or three 7in cocnrete blades

Would probably work fine. It wouldn't cut through more than maybe 2.5-3" of concrete, so you'd have to do the same "score and break" method as with the angle grinder, but I can't think of anything that would stop you outright. Concrete dust might be hard on the saw that's not well-sealed against it, IDK.

Which reminds me, you'll want a respirator for this. Cutting or grinding concrete produces more dust than you'd think possible, and it's nasty, fine silicate dust. A cheap dust mask won't do. If you don't have one already, a half-mask respirator is a very worthwhile investment.

>how much are blades? $20? do concrete blades ever explode like metal cutting discs?

$20 would get you name-brand discs, even. 7" blades can be had for ~$10 in 2- or 3-packs. You want the segmented ones, BTW. And no, they don't explode.

>>2461273
I want to learn technique for building ramps with no fill, using 'quik-tubes', but it seems like it uses a lot of lumber (re-usable?) for the forms. also i imagine you need a lot of rebar for that. i dont have a free rebar source.
also i imagine it requires concrete experience of which i have very little. ive hit up some skaters in the city to see if i could join them on any pours but i havent really gotten any responses.

>>2461299
the wall will be used for extending the quarterpipe above the pool
this ramp is 6ft high sotting 1.5foot above the 4.5ft tall wall.

I would like to have some 8foot tall sections of quarterpipe

also whats a cheaper alternative to cinderblocks? ive been filling them with 3 to 6in rocks and some shitty half assed home made concrete with less cement than usual.

>>2461451
$100 bucks should cover gas within 30miles for a dump truck, ya?

>shitsaw dust in tool
i have a shit ryobi angle grinder, i was thinking i would cut a 1inch deep square, ryobi roto hammer a bunch of holes in it and then hammer out the concrete

>silica dust
i have a fullface and regular respirator and n95 cartridges. do i need special silica dust cartridges.
this is post wwii military concrete. is there high risk of asbestos?

would using cement infused sand be similar to using foam as a filler?
would the vibration eventually make the cemented sand fall apart, or does the cemented rock become stronger over time?

>>2461502
>this is post wwii military concrete. is there high risk of asbestos?

Career USAF here and no. Old concrete is cut all the time and Uncle is paranoid of asbestos. Buildings and pipe insulation are the usual places and those get abated when bases are closed.

Any dust filter will do and you can use them a bit longer by cutting out some panty hose then rubber banding that over the filters. Do not waste the toes as the feet are perfect for covering shop vac filters (I've not bought replacement filters except when I score another used vacuum) and other similar setups like my Makita handheld vac.

>>2461296
>You can get small generators from harbor freight
neighbors have generators and concrete mixers, its a pita to borrow them. i have no where to convienently store my own generator.

>How do you plan to use the angle grinder and rotary hammer without a generator? Battery powered tools don't last for shit when you're working with concrete.

i have two 4ah ryobi batteries, and i just bought two more 4ah batteries. im only cutting 1in deep,16linear feet and drill 4sqft in a session. i can just take my time doing it and swap batteries to not over heat. if i run through all three batteries, i throw them on the charger at neighbors house, and then work on something else with the last battery or go smoke cigarettes

also i have a neighbor with dewalt concrete tools who is happy to do this for me, but he is not always home. great guy. he also owns a hydraulic press, i wanna press a 1lb propane can.

>>2461497
It's hard to explain when and why you should use steel in concrete block walls to someone who doesn't work in construction with concrete.

In almost all cases you do want steel in your wall because blocks by themselves are very weak and the mortar base will not bond to anything particularly well.

You definitely don't want to fill your blocks with whatever shitty concrete mix you are using. The strength of the concrete inside the cells (the holes in the blocks) is basically all that keeps a block wall together. Without it you could pretty much just kick a block wall over.

There is no cheaper alternative to blocks. They are used so widely for a reason. They are cheap to buy and cheap to install. Your other options are a) a poured concrete wall, b) a rock wall or c) a brick wall.

The only time i would not bother using steel in a block wall in this skate ramp application would be if the blocks were layed no more than 2 courses high (a course is a horizontal row) and when the concrete for the ramp was poured there was a continual piece of concrete that went inside the cells of the blocks, to the top of the ramp and then onto the face of the ramp. So the whole thing would basically need to be poured in one go.

>>2461424
Get on Google maps and look for hold abandoned hotels in your area, lots of the have filled in pools with perfectly preserved pool block that is ready to skate as is. I have found probably 100 yards of pool block in my lifetime this way. The block on that quarter was from a 100 year old swimming pool, kind of cool

>>2461494
I've done both, the cheapest/easiest is make piles of free rubble in the general shape of your qp, form wood around it and use as much rebar as you can afford. With enough rebar, you don't even need sonotube.
I really don't like buying cinder blocks for a support wall. It feels wasteful, but sometimes it is nessecary. Remember, they build skyscrapers and bridges out of concrete it's not as fragile as people think

>>2461729
i have some construction engineering background, pls do elaborate on cinder block construction.... or could you help me out with any links? i figured the grout inside the cinderblocks was overkill... i figured filling them with sand wouldve ben fine... though i do have imagines in my head of busted up cinder block walls.

...how do i acquire affordable pieces of rebar?

>>2460051
Buy some masonry zip disks for your angle grinder and have at it. Won't be fun or fast, I'd suggest wearing a mask, or at least filtering it through a lung dart.

>>2461753
That's awesome and an excellent use of resources.

>>2461824
What parts do you want me to elaborate on my man? I'm happy to explain anything

>>2461756
>Remember, they build skyscrapers and bridges out of concrete it's not as fragile as people think
They don't build skyscrapers out of concrete, what are you talking about you larper

>>2461849
>That's awesome and an excellent use of resources.
give it back jamal, those pool tiles arent yours, theres a reason dumpsters are locked, stop being poor and by new, conserving resources is a jewish psy-op

>>2461874
>Modern skyscrapers are built with steel or reinforced concrete frameworks and curtain walls of glass or polished stone. They use mechanical equipment such as water pumps and elevators.
>https://en.wikipedia.org/wiki/Skyscraper

>>2462306
They're steel frames and they use concrete for floors and shit and obviously the foundation. The concrete isn't what's holding them all together. The steel is.

Concrete is weak as fuck and anyone who says otherwise just hasn't ever been on a job where the concrete wasn't done properly and it goes wrong.

>>2461861
I watched this video
https://www.youtube.com/watch?v=Qfw679NHSAs&t=190s
and it said to do basically what i did before, add a piece of rebar and fill every other void with concrete... i just skimped out a bit and filled like every 5th hole with concrete, and the end holes too. (though i forgot to grout between bricks)

>>2462392
Why I said use a shitload of rebar. Concrete alone is weak yes. Use rebar. With enough rebar and proper forms, the concrete will hold itself up once it's cured and the forms are stripped. Pic related. Bet there is a cage of #4 rebar inside of this thing

>>2462392
t. Guy who never had to demo steps to a porch where the lunatics decided to backfill the whole thing with concrete

>>2462613
Forgot pic. Been here in person btw, this thing is giant for no deck or no support wall. Taught me a lot

>>2462616
how do i build a ramp like this? does it require experience and lots of money in rebar and wood forms? i would like to utalize these 'sono tubes'

...or would it be cheaper/easier just to pay someone to haul in fill.... or reinforce sand with cement?

>>2463064
it would definitely cost a decent chunk of money to build a ramp like that. and you would need some experience building forms.

how do i learn the basics on building forms? youtube? find someone to teach me?

>>2463297
what is the money spent on? are the forms reusable?
i already have gravel and sand for the concrete.

how do i learn the basics on building forms? youtube? find someone to teach me?

>>2463387
I can get two or three builds out of 2x4s, maybe two out of osb
>>2463297
The one I built that is similar dimensions scaled down cost over 2k

>>2463469
>The one I built that is similar dimensions scaled down cost over 2k
can you give me a breakdown in materials?

>>2461502
if i can get fill for free, this cost me about $100 in portland cement, $50 in cinder blocks, $20 to get brackets welded onto coping, $40 to get the seams cut in the concrete + fuel and labor
the wood was free scrapwood.

Skaterfag general?
(I was too lazy to pull the stump like last time

>>2463387
You can reuse forms tons, not 2 or 3 times like the guy said, but dozens of times for plywood or 2bys

>>2463700
Maybe if you're making dozens of identical obstacles. What if you need to cut an already cut 4x8? Unless the second ramp has tighter transition, you're only getting one use. 2x4s get cut to specific sizes, and screwing them back together multiple times is not as practical as just buying new ones when they only cost $3

>>2463679
i helped build one of the obstacles here. it was my 2nd concrete experience.

first was a 3bag kicker ramp about an inch or 2 thick of concrete and still hanging around

>>2463679
i helped build one of the obstacles here. it was my 2nd concrete experience. first was a 3bag kicker ramp about an inch or 2 thick of concrete and still hanging around.

how come those cinder blocks arent mortar'd in place? is this guy >>2461729 over-engineering stuff?

>>2463707
>Unless the second ramp has tighter transition,
why couldnt i reuse the form if multiple quartes have the same transition? my last quarter was 6ft with an 8ft transition, 8 feet wide. then i used the side forms to extend it another 4 feet, but by the end of that, theyre pretty bowed out.

also 2x4's at my rural hardware store were $8/ea not $3/ea

>>2461497
>>2461502
how would i go about adding a slanted cinderblock "china wall" to the top of this quarterpipe design?

>>2463781
At this diy? We probably know each other

>>2463786
Osb lasts like two weeks exposed to the elements

>>2463790
The answer to every question you have is osb, 2x4s, cinder blocks rebar and concrete

isnt ply like only 20% more expensive than osb?

>>2463953
graveside?

>>2464152
Yup. Wow that's really surreal. Are you planning on building anything here?

>>2464152
You without a doubt know me, maybe not my name but my face. That is infact graveside.

>>2461502
Is this twin towers in south carolina?

>>2461511
You can rent generators or welder-generators but I use a large inverter connected to my truck battery with jumper cable clamps (good ones) for easy swap between vehicles.

>>2463387
Forms need to be built so they are strong enough to hold up the weight of the concrete. For example. the platform of that ramp looks like at least a yard of concrete which weighs 2000lbs. You need to build a wooden structure that can hold up 2000lbs, so you would need some basic carpentry skills. You definitely don't want your forms failing while you're pouring the concrete.

>>2463781
The mortar isn't what makes blocks strong, it's the rebar/concrete inside of it that locks it all together and the footing beneath it. You can build a block wall that has no mortar between the blocks but you will never get it level. Level = strong.

In this pic >>2463679 there is also no footing for that block wall which means it's basically structurally worthless. I'm assuming it's just there to hold the fill into the area. That's not even to say that the way it is built is bad as far as a DIY goes, like it doesn't need to be that strong, but if it's in an area with earthquakes or floods it wouldn't take much for that quarterpipe to collapse.

I'm not telling you to over-engineer anything but if you want shit to last you should at least make an attempt to do it right.

>is using rebar in block walls over-engineering

>>2464221
>>2464223
>>2464226
no, i am in the desert.

>>2464240
ive used an inverter + truck to run a concrete mixer, but i hear that combo will ruin tool batteries
...how come that combo will ruin tool batteries, but a 12v ryobi car charger wont?

>>2464407
Tired of explaining this one. Block walls in skatepark building are the most idiot proof way to get your concrete to stay in place while curing. Once it's cured, the wall has done it's job and no longer has anything to do with holding your feature up. I have dug out backfill from under finished quarter pipes and reused it. concrete with enough rebar will hold itself up. This is the step to not skip. 4inches thick minimum, a CAGE of rebar and you're good. Sure it may sink or whatever but that's years from now. It's a fucking diy, the city is gonna tear it out in two years anyway. You need to move fast and break things while you still have control of the property.

>>2464411
See>>2462616

In many ways, yes it is. The block wall isn't necessary in the first olace

>>2464619
can i skip the rebar cage if i am making a base out of rock and shitty concrete mix? as seen in >>2461497

where do i even buy rebar and how much is it a foot?

>>2464619
can i skip the rebar cage if i am making a base out of rock and shitty concrete mix? as seen in >>2461497 surely this design wont sink.

where do i even buy rebar and how much is it a foot?
looks like on home depot, it varies from $0.75/ft to $3/foot. could i just sub in lengths of scrap steel instead?

Ive always been told to ask constrction site for scrap material... but it always seems so awkward, everyone seems so busy, who do i search out to ask? the guy sitting in his truck on the phone? a busy laborer? what kind of sites do i go to ask on? small house being re-roofed? big commercial site where i just drive in the gate and start lookin for someone to ask?

halp me build... ive already put up some really cool shit last year
cant believe i only bought a set of ryobi tools about 3 years ago, ive built sooo much crap since then!

>>2464738
If you skip rebar your shit has maybe a year before falling apart.

Steal. You're a skateboarder. You are no stranger to breaking laws. Go to abandoned factories and cut up chain link fence and use that. I have done this, and it is incredibly resilient as a rebar replacement. I have also gone to fab shops and stolen from dumpsters to throw into the forms as rebar. You need long pieces of steel in your 4-5 inches of Crete. You can skip a lot, but don't skip rebar. Tubing, fencing, machine shop shop scraps, tent poles, shade shelters etc can all be thrown into a form before the wet Crete is added

>>2464438
Hey man, I hate to pester you but how did you recognize our spot from that one shitty image, especially from a thousand miles away? All of the builders here are scratching our heads. This was an empty lot 4 years ago, are we finally making the big time like fdr?

>>2464822
the bricks, little arch and the "de"
im trying to become the next burnside/fdr

>>2464738
you can skip the rebar if you do the wall roman style
the majority of it is stacked rocks with liberal amounts of concrete almost all the way to the edges leaving the final inches open to the concrete to make a nice smooth surface

>>2465370
>you can skip the rebar if you do the wall roman style
is pic rel >>2461497 roman wall style youre mentioning? google gives a lot of diferent results for "roman wall style"
would this be a "roman style quarterpipe"? lol

...can i use a diluted concrete mix for that filler area?
9 parts sand, 6parts rock, 1 part cement,
instead of 3part sand, 3part rock, 1part cement?

>>2465370
>you can skip the rebar if you do the wall roman style
is pic rel >>2461497 roman wall style youre mentioning? google gives a lot of diferent results for "roman wall style"
would this be a "roman style quarterpipe"? lol

...can i use a diluted concrete mix for that filler area?
9 parts sand, 3parts gravel, 1 part cement,
instead of 3part sand, 3part gravel, 1part cement?

>>2465415
yeah but you mix concrete into the main body of fill
you do it in layers and use good concrete in the top if you can afford the extra couple bucks buy the latex additive for the final layer it prevents cracking they use it on bridges

>"Beach and desert sand are too dirty, too full of impurities and even too rounded from constant tumbling in water or from wind to used for a quality concrete product."
considering i have shit home-made concrete, do you think i should use sac concrete for the edges and seams of the ramp, and home-made concrete for the majority of rest of the ramp? would it be worthwhile to add in 1part sack concrete for every 3parts of home-made concrete that i mix up?

I also have a lot of super fine 1/8in gravel... would it be good to mix up a batch of 3part sand, 3part 1/8in gravel, 1pt cement and slather that into the final surface of the ramp?

>>2465418
is 1gal jug of ardex the same as 'latex additive'?
I was told i could also just use buckets of latex paint.

>>2465426
you want something like this https://usa.sika.com/en/construction/floor-covering/tile-stone-installation/accessories/sikalatex-r.html
paint has too much other shit in it. it might work but the real shit is cheap enough you only need about a cup worth per bag of concrete

>>2464619
>Tired of explaining this one
Because you're fucking retarded?

You have no idea how much engineering goes into building a ramp like this >>2462616. There's probably a huge footing beneath it and the re-bar isn't as simple as just a 'cage'.

It takes like barely any extra effort to do shit right so it will last for decades, yet you just justify being retarded, cheap and lazy by saying 'well it's gonna get torn down anyway'.

>>2464800
>cut up chain link fence and use that
>he thinks his 1/8" mesh is going to be strong enough to hold up his 2000lb freestanding ramp when it starts inevitably cracking

Lol

>>2465975
but how much engineering is there behind this ramp utalizing sono-tube >>2463064 can the work be much sloppier if you support it with sonotube?

>It takes like barely any extra effort to do shit right so it will last for decades
it sounds like cost increase dramatically when i want to do it right
how many feet of rebar should i be using for a ramp/quarterpiep surface 8x8feet?... from what i understand it will be about $2/ft?

additional questions:
how do i bend the rebar to fit the curve of the ramp?
can i substitute scrap, metal poles for rebar? from what i understand it will be better than no rebar but still an inferior strength compared to actual rebar with ridges that grip the concrete...
and from what i understand if i am using boulders and concrete as fill material, then i shouldnt even need rebar, ya?... or i could get away with just using a few scrap pieces of rebar, ya?

another question. if i cannot get the rebar to fit the curve of the ramp and some of the rebar is like an inch or half an inch from the surface, is it doing more harm than good? as it that shallow area of concrete will be much more prone to cracking? do my words make sense? let me draw a picture

>>2465975
How many skateparks have you worked on? You probably are speaking in terms of building bridges and sidewalks. With my own two hands, I have made shit like the free floater work (with help of course)
You don't know shit about skatepark building. Stick to driveways

>>2466049
You're gonna have to just prove a lot of these faggots wrong by just doing it. Watch this https://youtu.be/Zj-nPyxxFRs and realize mark Hubbard was too high on heroin to walk or see straight and was able to """engineer""" his way to 20 foot tall over vert cradles and other supposedly impossible features, according to these math fags.

>>2465976
I can physically point to a free standing ramp I have made years ago. Can you?

>>2466078
I have worked on more concrete projects than you ever will in your life and the difference is that we have to guarantee our work so we actually make sure that it will last. You would do well not to be so arrogant that you actually think you know more about concrete than a guy who does it for a living.

>>2466080
You don't think Grindline has a team of engineers that help design features like oververt ramps? There is so much liability when companies build skateparks, you're insane if you think they don't have guys engineering that those kind of features.

>>2466049
>how do i bend the rebar to fit the curve of the ramp?
Stick it in a vice and tweak on it until it's the right shape. You can also get a tool like pic related, we call it a 'hickey', they're fairly cheap. If you're not trying to do a freestanding wall and the load of the ramp is being supported by some kind of load bearing structure then you can use mesh like the other guy said.

I'm fairly sure this ramp >>2463064 is at lower bob's and the guys who built that actually work in construction for a living so they know how to build forms that will support concrete adequately.

>if i cannot get the rebar to fit the curve of the ramp and some of the rebar is like an inch or half an inch from the surface, is it doing more harm than good?
Yes. Use mesh instead.

>>2466080
>mark Hubbard was too high on heroin to walk or see straight
I don't think you have ever been around a heroin addict in your life

>>2466111
they possibly didnt in the 80's 90's when they first started building them.

>>2466117
what are some of the key strength differences between wire mesh and rebar?

>>2466117
>I'm fairly sure this ramp >>2463064 (You) is at lower bob's and the guys who built that actually work in construction for a living so they know how to build forms that will support concrete adequately.
how do i get a crash course in building (ghetto) forms? how do i contact these guys to see if i can join any of their projects for the learning experience?

The concepts are covered well here.
https://www.youtube.com/watch?v=ttpef8_kyg4

>>2466137
Mesh will just keep the concrete in one piece if there is no pressure from gravity. It has no structural use. Like if you tried to make a ramp like >>2462616 with mesh then if the concrete cracked in the middle the ramp would start falling over backwards and the mesh would do nothing to keep it upright.

Rebar, if used correctly in conjunction with an engineered footing, would probably be able to keep that ramp upright because it is much thicker and won't bend as easily under the weight of the ramp.

Basically, mesh is just used to keep the concrete together while rebar is used to reinforce it. Sometimes people use rebar in concrete that does not need reinforcement but this is going out of fashion in the construction world and mesh is being used much more often.

>>2466138
>how do i get a crash course in building (ghetto) forms?
Just look up youtube videos of people building forms and shit for walls or parking structures. Take notice of how they brace the forms so they don't fall over or go out of plumb when the concrete is poured. Concrete forms aren't that complicated if you're just building small freestanding ramps, you just need to understand how to do basic carpentry. Check this video, these guys make a form for a pretty basic mini ramp that ends up being all concrete. https://www.youtube.com/watch?v=I_g-46H5pso

>>2466108
>Never built a skateboard ramp
>Angrily giving advice in the skateboard ramp building thread
Objectively cringe

>>2464438
>...how come that combo will ruin tool batteries, but a 12v ryobi car charger wont?
It won't ruin tool batteries, unless you use an inverter so terrible that it somehow manages to make the battery charger malfunction. Get a pure sine wave inverter. 500w is plenty if you're just going to use it for charging tool batteries and not run AC tools right off of it, if you're looking to run things like a concrete mixer/saw/drill off of it then I would recommend getting a 2000w inverter.

>>2466395
>if you're looking to run things like a concrete mixer/saw/drill off
i thought concrete mixers use lower power but just have a really high gear

ty for the videos, i will be watching those..

Watch this
https://youtu.be/cZINeaDjisY https://youtu.be/3xw9_33uNJA
Disregard the fags saying you need an engineering degree to build a quarterpipe, that is ridiculous

>>2467056
i have an engineering degree and i have been watching lots of videos on how people build ramps and ive seen some atrocious shit... you know what else i have seen? those same terribly built ramps continue to stand.

IVe been putting up shittily built wood ramps for a few years now, and the designs keep getting sketchier and sketchier and they keep not falling apart :D

>>2467095
Why build a shit ramp when with a little extra effort you could build a good ramp?

>>2467339
>Why build a shit ramp when with a little extra effort you could build a good ramp?
becuase many times it is much more effort and much, much, much, more money to do it the right way

>>2467339
>Why build a shit ramp when with a little extra effort you could build a good ramp?
becuase many times it is much more effort and much, much, much, more money to do it the right way

Taking skate feature building advice from pro tradesmen who have only poured patios driveways and sidewalks is like asking a house framer for advice wood turning a bowl. Sure there's some overlap that may be worth listening to but when it comes to specifics there are things that they just don't know, because they don't have to know them.

>>2467795
What specifics are you referring to? Forming, pouring and finishing a flat concrete slab that will last decades is a simple task yet objectively much more complicated than the little ramps you have made.

Anyone who has worked professionally with concrete would easily be able to do anything you are doing at your little skatepark. There is nothing complicated about it and the fact that you skip any structural integrity in your ramps because you're a cheap fuck does not mean you know more than a professional.

>>2468441
Clueless
Concrete is objectively retard monkey work. It doesn't matter where or how. It's all for felons and drug addicts. Skatepark builders get paid double what you're average foundation/sidewalk worker gets paid

>>2468735
If you get paid so much how come you are mixing your concrete on the fucking ground with a dirty shovel

>>2468735
>Concrete is objectively retard monkey work
The fucking cope lmao. You would have literally no idea where to start with a foundation for a house.

>>2468735
>Skatepark builders
Yeah dudes that build shit like pic related. Not little speedbumps like your pic >>2467795

>>2468739
He doesn't know how to use a mixer

>>2468779
>He doesn't know how to use a mixer
how do you quickly clean a mixer... i could probably youtube that
>no hose, just gallon jugs of water

>>2468796
As soon as you're done mixing you just put water in it and let it spin. Tip the water out after it's been spinning for a few minutes and it should be fairly clean. Get the rest with a sponge. If you have big chunks of dry concrete in there you can chuck a few medium sized rocks in the mixer for a few minutes to bang them out.

I don't understand why people do this mixing on the ground shit. Anything is better than that. G a mortar hoe and mix in a wheelbarrow if you can't afford a mixer.

Btw you can actually buy small mixers for fairly cheap like this model from lowes.

https://www.lowes.com/pd/YARDMAX-4-0-CU-FT-Concrete-Mixer/1003002896?cm_mmc=shp-_-c-_-prd-_-sol-_-ggl-_-PLA_SOL_146_Riders-Powersports-Chore-_-1003002896-_-online-_-0-_-0&gclid=CjwKCAjwg5uZBhATEiwAhhRLHkUwOdz-aMZ7Yp-umHaUUQ-a0D0j-KLosxTW152AEMqjrJuWa4AnxhoCVa8QAvD_BwE&gclsrc=aw.ds

Or you could look on craigslist, people probably buy these and use them for one project and then sell them all the time. Harbor freight has some cheap ones too. They hold about 2 60lb bags of concrete per load.

If you're doing your own small concrete jobs it's basically invaluable to have your own mixer and these ones are light enough that you and a buddy could basically pick it up and put it in the back of your truck easily. You don't even need to tow it.

You got 4 buddies wanting to build diy shit? Each of you chuck in $80 and buy a fucking mixer and save yourselves hours and hours of mixing time.

>>2468799
>G a mortar hoe

Fuckers won't help out and called me a bitchass POG. Imma call their functional so they get orders to Hood.

>>2468810
Sorry I meant GET a mortar hoe. Like this.
https://www.lowes.com/pd/Marshalltown-18-in-Wood-Handle-Mortar-Hoe/5013023197?cm_mmc=shp-_-c-_-prd-_-bdm-_-ggl-_-LIA_BDM_210_Concrete-Block-_-5013023197-_-local-_-0-_-0&ds_rl=1286981&gclid=CjwKCAjwg5uZBhATEiwAhhRLHre0UFgX55wfXNLk4tJoQ6YuuEYISDxM6rTGAsYLMdXUQNhliru_NhoC7mMQAvD_BwE&gclsrc=aw.ds

A normal square shovel works fine too but the mortar hoes make it a bit quicker and easier

>>2468799
>I don't understand why people do this mixing on the ground shit.
i only mix like 5-10gal of concrete at a time. it takes about 5minutes to mix up the rock/sand/cement, and then about 3 minutes of elbow grease to mix up that much concrete and water,
clean up: dilute whatever crud is left on the floor with water, scrape once with a shovel and the floor is good. (about 30 seconds)

what i should do is use the mixer to mix the dry ingrediants for me, but i feel that may get insanely dusty.... maybe just mix up a big dry batch of concrete all at once, then use mixer on pour day.

question: how long can concrete sit in mixer between cleanings, before it starts to harder to the crud coated walls? 1 hr? 4 hours?

>>2468803
neighbors have a mixer and a generator, but it is always a pain in the ass to borow tools. also fumes sometimes start collect in the pool when using generator in there, or especially when idling a vehicle. ill bring an extension cord.

Remember with a mixer, someone still has to lift bags up into the mixer, which is potentially even more work than shovel mixing, then you gotta dump it out to shovel it anyway. It's not an automatic process like shotcrete. It's a little less work but not much less

>>2468799
We like to mix on the ground in front of the feature when on asphalt, the cream from the concrete cures into the deep pitting in the slab and makes a much much smoother surface for a few weeks. It also works on rough patches on an aged abandoned slab.

>>2468829
It'll sit in a mixer all day and you can still scrape it off at the end, keep water in the mixer
A bottle of hydrochloric acid also helps

>>2468848
>and you can still scrape it off at the end,
is that as easy as instructions mentioned here: >>2468799

note the mixer i have access to has aged concrete crud all over it. will that bang out with rocks?

>>2468835
>someone still has to lift bags up into the mixer, which is potentially even more work than shovel mixing
Are you serious?
Hmm i wonder why professional masons don't just mix on the fucking ground then lmao. Like why do mixers even exist when you can just dump out your concrete onto the ground and mix it right there?

>>2468829
Wait so you're making your own concrete mix? Are you trying to save money? Why not just buy bagged concrete and save the time of mixing it yourself?

Concrete on the inside of your mixer will probably start curing within like 30 mins. The trick is to never let it build up in the first place.

>>2468853
>the mixer i have access to has aged concrete crud all over it. will that bang out with rocks?
Some of it, yeah. It's not even a big deal if the mixer is dirty though. A dirty mixer still beats mixing by hand.

>>2468853
No it's not that easy, you'll always have shit caked on that needs cleaning, but it's a lot faster with a mixer

>>2468854
>Wait so you're making your own concrete mix?
i have easy access to sand, rock and water, i buy portland cement from 15miles down the road and they even deliver. i have access to a bunch of barflys who will work for (free) weed, some are amazing workers, others are terrible workers.

>>2468857
Fair enough. You don't have to mix all of the shit dry though. You can do it in a mixer and add water at the same time.

When you say you have access to rock do you mean gravel right?

https://www.youtube.com/watch?v=uaOWoUtQC10

>>2468860
You dry mix when you don't need thr concrete right away, that dry mix might sit for days
If all he's doing is 2 or 3 bags of concrete a day there is no point in anything other than some random scrap bin and a shovel

>>2468862
>making cut marks on your straight edge

Why would you ever need to cut a cement bag in half either

>>2468864
>Why would you ever need to cut a cement bag in half either

>>2468863
If he's building a ramp he's definitely using more than 2-3 bags of concrete.

preventing sag in a quarter pipe:

please explain to me why this is a bad idea for pouring a wall towards vertival, pic rel.
what if i poured one layer at a time... let it harden for an hour then poured the next layer, let it harden for an hour and then pour the next layer....
would each layer not bond well to the previous layer if there was a ~60minute break where it was allowed to harden?
what if i were to do thnner layers of concrete and give each layer 30 minutes to harden instead?
in a 6hour pour, i could have like 12 layers on a 6 foot quarter, the bottom layers being about a foot in elevation gain, middle layers around 6in in elevation gain, and final layers being only a few inches high each pour.

also why couldnt i do a pour in two days with a seam 2/3 up the ramp? surely a seam would be preferable to transition with an anti-pop lump in the center, aka sagging, ya?

>i used this method to build the last quarterpipe

>>2468860
>When you say you have access to rock do you mean gravel right?
yes, its about 3/8ths rock with a lot of left over tiny 1/8 or 1/16th rock. i would like to use a mix of that fine rock for the surface of the ramp. is that a bad idea?

also the rock is somewhat rounded, from what i understand it will be weaker... does that imply a big slab may crack easier or it will just weather away much faster? ...both?

>>2468868
This method is called hand stacking. it is the alternative to shotcrete. A lot of the vert at fdr is hand stacked.

You shovel it in as high as it will go, screwed down, handstack a layer, screwed down again, handstack a layer etc. Once you get to vert, you really can't screed again. What I like to do is start magging and sealing up the very very bottom while the vert cures, moving up and sealing higher and higher. Once it can support itself, it's already pretty cured and you have to scrub the life out of it with floats. Seal the whole ramp, check for lumps from the side and then either cut them out or scrub for the life of you. A lot of vert pouring without shotcrete is about waiting, and knowing when to take action. You really have to give it your all to seal up vertical sections. Once it's cured enough to support itself, it's pretty fucking cured. You have to hustle. Once everything is sealed and magged, I finish it all together. Then let it cure, wet the whole thing, and hit it again. If you're satisfied soak it all in water to let it wet cure which makes for a stronger surface.

I would not half the qp horizontally. The only time I have seen this IRL it turned out like dogshit. If you need to do it in two shots, seam it vertically down the middle.

>>2468880
>screwed
Meant skreed

Another alternative to hand stacking is using a piece of plywood screwed into the face of the ramp covering the entire vert section. Then you pile it up from the bottom much like the last method, and once you get to vert start shoving concrete behind the plywood from the top. Once it's filled you can vibrate your plywood and wait. Pull the front form and finish. I have used both of these methods and I prefer handstacking. Using a vert form on the face usually causes vertical sagging in the center from all of the weight of the concrete pushing on it, and it's usually too big to cut out/scrub in. Some people swear by this method but there's just too much that can go wrong that you won't see until you strip the form. If you're going to do this, you need to brace the hell out of your vert form to keep it from bowing out. It is less work than magging half cured concrete for hours but I don't ever see it turn out as well as hand stacking

>Download Windows 8.1 Disc Image (ISO File)
im pretty sure this is the disc i made when my windows 8.1 asus laptop crashed. can i use it for "resetting" my windows computer?

>>2468885
i also did that method on the top of the first quarter i built. i let it harden a bit and then just used a screeed to dig out the excess. it worked out pretty welll.

*my first quarter was 6 ft tall, 8 foot wide, and my second quarter was just extending it another 4 feet wider... it came out pretty damn good aside my my helper doing some stupid shit.

fucking idiot. he insisted on getting the concrete smooth first and then trying to get it level and "skreeded" from there... of course using his eyeball as a level instead of a 2x4
WHY WOULD OBSESSIVELY SMOOTH IT OUT BEFORE IT IS EVEN LEVEL? WHAT THE FUCK IS WRONG WITH YOU?

^^^i just let him do it becuase i didnt want to trowel, he made it seem painstakingly labourus and then finally when i kicked him off the job and started trowling myself, it was easy!

also concrete needs to be agitated to get ird of airpockets, yes?
i kept asking my helper to do this and he wouldnt. i would just jab into the freshly poured concrete with a piece of rebar a bunch of times and then start shaping and smoothing, is that adequate or even necessary?

>>2468888
It's really not that big of a deal at those sizes. If it works it works. Once you get up to 6, 8, 12 inches past vert, or even higher, it becomes exponentially more important to do it right, because there is no other way. If he tried that dumb shit on vert he would learn very quickly it is not right. For someone who has worked w concrete twice you seem to have a pretty solid grasp of what to do

>>2468891
What are concrete vibrators? They range all the way up to tracked units almost capable of stirrin' yer mum.

>>2468905
Looks like a big snake that you stick into the mud around the edges of the form and vibrate the mud so there are no air pockets at the edges. Not necessary for small shit but it doesn't hurt. Otherwise just tape the sides of your form to make sure all those little air pockets get filled

>>2468905
>>2468940
Not as important on smaller stuff but a cheap alternative to these is to take the blade off of a saws all and vibrate the guard against your forms

>>2468978
>Not as important on smaller stuff
why?

>>2469009
Having air pockets is bad because it's a weak point in the concrete. If you're building some small shit like >>2467795
then there it doesn't even need to be strong so it's not a big deal if you vibrate it or not.

>>2468863
>>2468863
Every ramp I have ever worked on has used around a whole pallet, sometimes over two. Id say the average diy pour is around 40 bags. I don't think you can really make much of anything with only 3

what do construction companies do with wood used for form work? re-use it one or three times then trash it? use it till it breaks?

I am contacting local contractors to see if i can pay them to bring in fill material... should i ask if i can purchase thier old form wood as well?

also how do i find small time contractors in the area who do shit like driveways and sidewalks? i type in 'concrete contractor' into google maps and get like 3 total contractors in a 60mile radius

what do construction companies do with wood used for form work? re-use it one or three times then trash it? use it till it breaks?

I am contacting local contractors to see if i can pay them to bring in fill material... should i ask if i can purchase thier old form wood as well?

also how do i find small time contractors in the area who do shit like driveways and sidewalks? i type in 'concrete contractor' into google maps and get like 3 total contractors in a 60mile radius

>>2469451
Ask them in person. Of course the workers will gobble what ever the boss does not but you might luck out. Old mobile home frame beams make nice forms too. My bros use them often. I use heavier beam so my foundations are my forms but that's obviously not optimal for sidewalk.

>>2469451
Harrison street in Kansas had local contrsctors dump their fill at the diy to the point where they had nowhere else to put it, once the skaters started turning trucks away they'd just come at night and dump more illegally. I'm not sure how they resolved this, it was going down right when I was passing thru the area in 2020

have you tried not being a degenerate skaterboi and growing up?

>>2469472
>Old mobile home frame beams make nice forms too. My bros use them often. I use heavier beam so my foundations are my forms
i am having trouble visualizing what you are saying? are you talking about the two ibeams that make the frame?... is this the form for a flat slab or the form for a ramp?

I have a 16foot trailer frame and i want to make a china wall for it. i havent really began thinking too much about the logistics for this, but this is my idea. 3 sheets of ply for the flat part and then a seam made of wood or concrete. i figure i would find two beams and bolt them to the frame for a support. i have a welder friend who could do any bracing for me.
i imagine the steeper i make it, the sturdier it will be.... or at least the less hard riders will slam into it*

>>2469478
big city problems. im rural.

>>2469478
big city problems. im rural.

home depot sell 25lb box of 3in screw and 25lb of 2.5in screw for $50, but they dont seem to stock 2in or 1.5in screws in these 25lb boxes. where can i purchase 1.5in and 2in screws at $2/lb? local hardware store sells them in bulk for $6.50lb

>>2468880
Why aren't they formed with more of a dry pack like deck mud then maybe topped with a surfacing mix like resurfacer or vinyl?
I'm down a weird rabbit hole of pozzolans and learning how to mix my own concretes because I'll be damned to pay $25 for a bag I can just spin up myself. I see the occasional tile, tuck, or stucco hell job but it's not something I do enough of to be highly competent.

>>2469451
>re-use it one or three times then trash it?
Yep.

>how do i find small time contractors in the area who do shit like driveways and sidewalks
Look up masons instead of concrete contractors.

>>2460784
>cordless

Enjoy your seven seconds of battery life. I bought a nice old worm gear saw on Craigslist for $35 and used a harbor freight blade to do a bunch of cutting on an old concrete slab. It worked fine.

^^^ my buddy is giving me a low power, compact generator! it looks like absolute shit, interface panel falling off, half the casing broke off, lol

>>2463064

Hot wire styrofoam blocks? xps is pretty strong in compression, it'd probably work ok for molding the concrete. Or whatever you do with concrete. You could even just coat the foam in fiberglass and use it as is, but it'd have flex, like a diving board. And the wheels would dig grooves.

>t. never done anything with actual concrete (obviously)

>>2469815
lots of skatepark builders use styrafoam blocks as filler. where do i get styrafoam blocks for cheap in the middle of farmland no where?

>>2469824
You have to strap them down they're so buyant they'll force themselves out of wet concrete which is potentially worse than a blowout

>>2469792
Don't matter if it works.

>>2469824
>where do i get styrafoam blocks for cheap in the middle of farmland no where?

seriously? flotation billet, housing insulation, rigid board insulation, raid a fuckin' supermarket and steal it out the walls. Also, contractors have extra lying around after they finish build the walls for the supermarkets and shit.

>for cheap

XPS is the product of an engineered, refined and constantly monitored process involving some pelletized bullshit. its entire purpose is to take up literally as much space as humanly possible, while still being cheap. There's no such thing as XPS that isn't cheap. The stuff you put on top of it, the way you shape it, how rigid it is, every other part of the project is going to be way more of a pain in the ass, in terms of getting the right feel on the kickin' 360 noscope tailslides... or whatever you do at those establishments.

>>2470122
>while still being cheap.
cheap includes shipping and handling. i am 45 minutes from a city big enough to have a walmart.

i drive a small truck with a 6foot bed

https://www.youtube.com/watch?v=0G0Thypcy_E
They're cut into the dirt, they have that crazy concrete gun just blasting it in, and it still takes 10 people to hard trowel the finish and tranny.

>>2470734
Wtf I know these dudes. This is pat from the lost bowl in Virginia, and another guy finishing is named JT Gleason and he helped a ton with the big diy in Asheville, NC

still trying to figure out if cemented sand is my best option for backfill... any estimate on cuyd it would take to backfill 8ft of a five foot wall? as seen here:>>2461497
how many bags of cement would it take to take to 'sandstone' that back portion?

im still trying to figure out if cemented sand is my best option for backfill... any estimate on cuyd it would take to backfill 8ft of a five foot wall? as seen here:>>2461497
how many bags of cement would it take to take to 'sandstone' a cuyd of backfill/sand

^^^my rough estimates say about 1.5cuyrd +/- 0.5cuyrd

bump

It's time to dig

>>2470983
idk any of them but they make a nice quarter

>>2472145
>that leaning block wall supporting like 6000lbs of concrete and fill

>>2472145
these cinderblocks have rebar running down into the ground?

>>2472349
most of that weight is being directed towards the ground.

>>2472349
While a retard digs behind it

>>2472349
They're completely filled with concrete, mortared together and with rebar running down into a concrete footer. It is damn near up to retaining wall standards. It doesn't have to win beauty contests
>>2472449
Not just the ground, into a concrete footer, past it into the earth, and tied into the rebar in the footer. You could rock to fakie this bitch w a Honda civic it's not going anywhere

>>2472515
Absolutely no where is 6 feet of cinder block code for a retaining wall

>>2472515
>It is damn near up to retaining wall standards
>visibly out of plumb
KEK

>>2470734
I wanna see more of the thick gal with the green hair...

>>2460051
Just bolt a metal/wood wedge.

>>2472961
thicc portland punx

are n95 cartridges on m3 mask good using around concrete sawing dust? any specific cartridges i should be buying?

what type of face mask should i use for mixing my dry concrete ingrediants?

>>2473673
Just cut so the dust goes downwind

>>2460051
are these the blades i want?

>>2460195
though im not sure what bits to get for the roto hammer...
i am looking for cheap as i have people who will put elbow grease into the roto hammer for me

Very unpopular opinion: Retard gruntwork days are the most fun build days. Touching the wet concrete is over rated, Instead of dropping a trowel selfie on your social media post a shovel selfie next to a big pile of rocks. Earthmoving days are more fun than pour days

>>2474008
Great opinion from a guy who works with his hands twice a year

>>2460108
Nothing more fun than concrete parks built by some concrete contractor since the mayor wanted to give the business to his brother in-law instead of the company that actually builds skatparks.

>>2474010
I'm full of them. Would you like to know more about how I feel about digging?

>>2460051
Can't think of a bigger waste of time than building a skate park ramp

>>2460149
The interface will be the weakest link, after a few thermal cycles you'll get an expansion joint regardless. You can see the vertical crack in diynotshit.jpg, it's just not a problem because it's small and flush.

>>2473673
I would only upgrade masks for silica fume.

>>2474113
>I would only upgrade masks for silica fume.
what kind of mask is fine for shoveling cement and grinding concrete?

cool thread

>>2474129
None, breath in the concrete and harden up you little faggot

im going to flea market on saturday
any tools i can pick up for much cheaper there?

wrench

https://www.amazon.com/NYTiger-Diamond-Grinder-Segmented-Concrete/dp/B08D8XH3YS/ref=mp_s_a_1_2_sspa?

https://www.amazon.com/Bosch-HC2083-SDS-plus-Bulldog-Rotary/dp/B00B4T1GB8/ref=mp_s_a_1_4?

https://www.amazon.com/SDS-plus-Hammer-Including-Cranked-Chisels/dp/B07CJGGMM5/ref=mp_s_a_1_18?

any concrete finishing tools that you recommend i buy? i have a triangle/spade towel thingy, a thick, rigid, flat concrete thingy about 4x10inches and a thin-bendy flat concrete 'float' thingy about 4x10in

>>2474979
Holy fuck dude can't you just Google shit yourself or watch videos to see what tools they use? Quit bumping this shitty fucking thread.

For small concrete jobs you need a wooden float, a finishing trowel and a pool trowel helps too. There are plenty of other tools you can use but you can pretty much do everything with those tools.

Fucking figure it out dude

>>2475150
>Fucking figure it out dude
do used chisel tips work decently compared to brand new chisel tips?
do diamond saw blades last for 1 cut or 50 cuts? is 3 blades overkill or not enough?

well i have to use the tools to find out and once i am in the middle of nowhere using those tools, i dont have amazon or flea marker to shop at, so ill be shopping at a rural hardware store with 3x prices... and as a big part of this project i about saving money, i am asking the questions here.

>Holy fuck dude can't you just Google
i do that before asking questions but theyre typically very broadly worded and usually not tailored towards money saving tips