Need advice on how to make a simple 10 inch cement form

[Unionville]

I'm getting so much great do-it-yourself here. Here's another question:

I want to repair my curb but all the youtube videos I've watched are for large projects.  Is there something I can use at home to create a simple form for this curb?  *It needs to have a curve.* I'm trying to avoid buying more unnecessary supplies. Can I do something as lame as cardboard covered in plastic being held up by rocks?  Any ideas?

[ncornilsen]

You need something with some strength. I'd get some Masonite siding and use that.

[Rural]

 Give some thought to how you're going to get the form to turn loose of the concrete once it's dried, too. I don't have a solution for that problem, mind you, but I do have firsthand knowledge that it's a problem. :-)

[HPstache]

Maybe something like a 5 gallon bucket ring that's cut into quarters?

Or, if that's too small, one quarter of one of those very large plastic flower pots?

[zolotiyeruki]

It's either Home Depot or Lowes that sells 4'x8' sheets of dry erase board, that would be perfect for curved shapes.  It's basically 1/8" MDF with a white board coating on one side.  Thin enough to bend easily, stiff enough to make the curve smooth, and smooth enough on one side that it should release easily from the concrete when you're done.

[Fishindude]

That's a pretty tight curve.  I'd use a piece of sheet metal for the form, held in place with wood blocking.

[Dancin'Dog]

That's a pretty tight curve.  I'd use a piece of sheet metal for the form, held in place with wood blocking.

You can probably scrounge the metal from an old metal can ( pineapple juice comes in a large can), you can screw it to the wooden side forms.

[Fishindude]

I will add, that you will need to "pin" that new concrete to the existing or first time you bump it, it will break loose.
Rent or borrow a hammer drill. drill holes in the existing curbs you are tying into, then hammer in some short pieces of steel rebar, leaving some protruding into the new concrete.
Hard to explain verbally, but hopefully you get the idea.

[lthenderson]

I will add, that you will need to "pin" that new concrete to the existing or first time you bump it, it will break loose.
Rent or borrow a hammer drill. drill holes in the existing curbs you are tying into, then hammer in some short pieces of steel rebar, leaving some protruding into the new concrete.
Hard to explain verbally, but hopefully you get the idea.

This was going to be my advice too but Fishindude beat me to it. Since finding short pieces of steel rebar can be problematic for city dwellers, I have used long bolts before. Drill a hole slightly undersized of the threads and then drive the bolt into the hole using a hammer. You can leave the head of the bolt sticking out because it will be imbedded into the concrete.

[Unionville]

I will add, that you will need to "pin" that new concrete to the existing or first time you bump it, it will break loose.
Rent or borrow a hammer drill. drill holes in the existing curbs you are tying into, then hammer in some short pieces of steel rebar, leaving some protruding into the new concrete.
Hard to explain verbally, but hopefully you get the idea.

This was going to be my advice too but Fishindude beat me to it. Since finding short pieces of steel rebar can be problematic for city dwellers, I have used long bolts before. Drill a hole slightly undersized of the threads and then drive the bolt into the hole using a hammer. You can leave the head of the bolt sticking out because it will be imbedded into the concrete.

If I can't get an electric drill with a cement bit, is there any way I could do this by hand?  I have a chisel (not sure if that would help anything)  I'm interested in the idea of hammering the bolt in with a hammer by hand.  But wouldn't it ruin the threads to hammer it in?

[zolotiyeruki]

I will add, that you will need to "pin" that new concrete to the existing or first time you bump it, it will break loose.
Rent or borrow a hammer drill. drill holes in the existing curbs you are tying into, then hammer in some short pieces of steel rebar, leaving some protruding into the new concrete.
Hard to explain verbally, but hopefully you get the idea.

This was going to be my advice too but Fishindude beat me to it. Since finding short pieces of steel rebar can be problematic for city dwellers, I have used long bolts before. Drill a hole slightly undersized of the threads and then drive the bolt into the hole using a hammer. You can leave the head of the bolt sticking out because it will be imbedded into the concrete.

If I can't get an electric drill with a cement bit, is there any way I could do this by hand?  I have a chisel (not sure if that would help anything)  I'm interested in the idea of hammering the bolt in with a hammer by hand.  But wouldn't it ruin the threads to hammer it in?

It doesn't matter if the threads get ruined.  You're not going to be using them again any time soon :)

[Dancin'Dog]

Masonry nails would be easier to nail into concrete than bolts.

[lthenderson]

I will add, that you will need to "pin" that new concrete to the existing or first time you bump it, it will break loose.
Rent or borrow a hammer drill. drill holes in the existing curbs you are tying into, then hammer in some short pieces of steel rebar, leaving some protruding into the new concrete.
Hard to explain verbally, but hopefully you get the idea.

This was going to be my advice too but Fishindude beat me to it. Since finding short pieces of steel rebar can be problematic for city dwellers, I have used long bolts before. Drill a hole slightly undersized of the threads and then drive the bolt into the hole using a hammer. You can leave the head of the bolt sticking out because it will be imbedded into the concrete.

If I can't get an electric drill with a cement bit, is there any way I could do this by hand?  I have a chisel (not sure if that would help anything)  I'm interested in the idea of hammering the bolt in with a hammer by hand.  But wouldn't it ruin the threads to hammer it in?

Just about every rental place I've seen has these for rent and like someone else said, who cares if the threads get ruined. It will be inside concrete for the remainder of its lifetime.

[Unionville]

Masonry nails would be easier to nail into concrete than bolts.

I was going to attach flexible barb wire between 2 bolts to give the concrete curve reinforcement inside (kind of like mini rebar).  Are nails strong enough to provide internal support?

[Spork]

I will add, that you will need to "pin" that new concrete to the existing or first time you bump it, it will break loose.
Rent or borrow a hammer drill. drill holes in the existing curbs you are tying into, then hammer in some short pieces of steel rebar, leaving some protruding into the new concrete.
Hard to explain verbally, but hopefully you get the idea.

This was going to be my advice too but Fishindude beat me to it. Since finding short pieces of steel rebar can be problematic for city dwellers, I have used long bolts before. Drill a hole slightly undersized of the threads and then drive the bolt into the hole using a hammer. You can leave the head of the bolt sticking out because it will be imbedded into the concrete.

If I can't get an electric drill with a cement bit, is there any way I could do this by hand?  I have a chisel (not sure if that would help anything)  I'm interested in the idea of hammering the bolt in with a hammer by hand.  But wouldn't it ruin the threads to hammer it in?

Just about every rental place I've seen has these for rent and like someone else said, who cares if the threads get ruined. It will be inside concrete for the remainder of its lifetime.

A nice hammer drill is awesome... and what you'll see at a rental location.

BUT.... an electric drill of some sort is something you would use once a week for the rest of your life.  Just buy one.  You don't have to buy a nice fancy hammer drill.  But buy one.  I've been through probably 6 (maybe more) cordless drills (and I still like them) but I still have the corded no-frills drill I bought in high school.  I still use it all the time.  Buy a drill.  Buy some concrete bits.  Be happy.

[lthenderson]

Masonry nails would be easier to nail into concrete than bolts.

I was going to attach flexible barb wire between 2 bolts to give the concrete curve reinforcement inside (kind of like mini rebar).  Are nails strong enough to provide internal support?

What you are going for when putting pins in concrete is to protect the joint in shear. Running a pin/wire between the pins in the existing concrete won't really strengthen anything but should the concrete crack in the future, it can hold things together so the pieces don't fall out like the original failure. Nails will work but I would be worried that they don't have enough shear strength if a tire should bump up against it.