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reinforcement

18 years ago

I have a question for all you tufa-heads, especially the old timers. How important is reinforcement? I mean I can understand the need in large pieces, but it seems like everyone's using it even in smaller pieces, bowls, pots, troughs. Is that necessary? I mean isn't concrete strong by its nature? Especially with adding fibers, being careful with recipes, etc? Partially my question comes because I haven't been using it much, except in birdbath pedestals (but not the bowls). All my planters seem pretty strong to me, but how can I tell? Drop them from heights? What should they be able to withstand?

Or do they last longer? Just wondering. Here's a link to a picture of a birdbath I made. (reinforced base). http://www.imago.iwarp.com/birdbath.html

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Comments (4)

billie_ann
18 years ago
I don't use reinforcement in my smaller planters or troughs and their quite old. You need reinforcement for very large pieces, over two feet for a trough. If you're building something tall and thin you need reinforcement. Maybe it seems like everyone is using reinforcement because their using the newer products that have fibers and admixes already added. A big plus for some people is the bags or containers that these mixes come in weight less than a bag of portland cement.

Quote="I mean isn't concrete strong by its nature?"
I'm talking hypertufa which is portland cement, sand and peat moss or whatever recipe you use. Not concrete which is portland cement, sand and an aggregate.
You really don't have to be too careful with a simple hypertufa recipe, equal parts portland cement, sand and peat moss. You do have to be careful adding dye, fiber, fortifiers and some exotic ingredients.

Couldn't get your link to work; I'll try again later. Billie
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rockyn
18 years ago
Very nice bird bath. I love the wee bird perched on the side. Is it a dove?

How did you make the base for it?
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tufaenough
18 years ago
Your birdbath is charming.
Reinforcement properly use is great but unless your piece is going to be stressed IMO you can actually weaken a smaller piece by using it improperly.
I suspect admix and extra sand or a bit more Portland in the recipe is probably the better way to strengthen smaller projects.
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magrit
Original Author
18 years ago
Thanks for taking a look at my birdbath. The little bird I just made from a handful-sized "lump" of tufa. It's not any kind of bird really, just a wee fat bird taking a drink. The base - I had a styrofoam cone shape, wrapped it in plastic and then motor-oiled it a bit. I shaped wire mesh around it in a shape I liked, then used the "cheesegrater" method of pushing in my crete mix, which was 1portland/1sand/ 2perlite. I pulled out the styrofoam cone so I could reuse it. The bowl is the same mix, with a thin layer of portland/sand on the inside, as I'd been having leakage problems with just the perlite mix. It's nice and light, but seems quite strong too. I think I'll try using my judgement on what really needs reinforcement. Some things are obvious, some are not. And that wire mesh sure can tear up your hands! I used chickenwire for years with my paper mache sculptures, and it was ok once I built up callouses, but for awhile my fingertips and hands would just be all torn up...
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