Copper or Bronze bar?

Black plastic is a LOT cheaper

Good grief! What in the world for? That's going to be pricey.

Pete Keillor

According to Pete Keillor :

And I would have thought that something like 1/4" thick tar impregnated felt would be a better choice, as that has some give if the temperature gets hotter than when it was poured. Copper or bronze will represent a serious problem under those conditions -- though the copper might crush a bit more than the bronze.

Enjoy, DoN.

HotRod, you're tossing away a lot of money very unnecessarily. If you're hell bent on using such a material, you'd do fine with brass, and it need not be thick, nor tall. Something 1/8" thick and a couple inches wide would be more than adequate. It's not necessary, nor desirable, to have the item make a total separation in the 'crete. Even scoring and finishing over the score will provide a reasonably straight crack, so anything that diminishes the thickness of the 'crete will provide a perfect edge.

Harold

I'm considering using the brass or copper just for the top and then metal for the bottom kind of like a T shape. However this is for a decorative concrete project that I am doing. The inlays are designed to weaken the concrete "in a design" where I want it to crack. This is not about the concrete expansion. I need to make sure that the inlay is a minimum of 1/4 through the concrete, the more the better. Any sources recommended.

I understand what you're doing-----but didn't know if you really needed the size of material you specified---which is much larger than necessary to accomplish the clean cracking you desire----but I can see the need for the

1/4" surface exposure for aesthetics, and agree, it would look great. Sorry, I don't have a clue about a source-----I'd likely go with something like 1/4" x 2" flat bar (brass), which would be more than enough to define the cracking you desire, and readily available from non-ferrous supply houses. Alaskan Copper comes to mind.

Harold

I've even thought about using copper pipe and adding the 3"-4" on the bottom to facilitate the look and cracking. How would copper pipe hold up in the rain and snow???

Rain and show would be the least of your worries if this is exposed to traffic of any kind. Copper pipe, if you're talking about the stuff that's readily available, is thin walled----too thin to stand up to much abrasion. Even K copper pipe has a relatively thin wall. Only if you went to schedule 40 pipe would you get a decent wall thickness. Assuming you feel K pipe (which is 5/8" OD for the 1/2" size) would be thick enough to stand up to the abrasion, you might want to take a chair along when you get a quote on material cost. You're sure to pass out. Same goes for the 1/4" thick brass.

I'm not sure why you feel you need to have it so tall-------it need not be unless the 'crete is thick---say 12'' or more.

My shop has a 6-1/4" thick floor, with hydronic heat. The guy I hired to place the 'crete said he could score the floor with his bull float, on which he has a skeg. After scoring the floor, he finished over the score so it wasn't visible. What that accomplished was to move away from the score line all the large aggregate. The only cracks I have in the floor are where it was scored, and while they aren't dead straight (they wander sideways a tiny bit, but never leave the general score area), they would have been had I installed a small piece of metal like I've recommended. All you have to do is give the 'crete a place to crack, and it will oblige you.

If your metal goes all the way through the 'crete, it's possible it will get displaced eventually. It's a good idea to have it bear on something instead of to make a full separation of the 'crete.

This project sounds interesting. What, exactly, are you trying to accomplish?

Harold