plaster help!

[AllisonR]

I want to make a huge (2+ meter / 7+ foot) hi-relief sculpture. It needs to be somewhat lightweight material, or it will weigh too much to move / transport / hang....

I made a test. I made the basic shape with wet crumpled newspaper, put saran wrap on top, and then used plaster bandage on top. The kind you use if you make a pregnancy cast. I put these strips in lukewarm water and then on the saran wrap and shapped it. And it dried in 5 minutes, which is great because it then held the form. The next morning I just pulled the newslpaper and saran wrap out. Fabulous. But....

These plaster rolls cost 2 dollars each, and I would need 2000 rolls or more - so 4000 dollars minimum. Well, no, there is no way.

Then I thought: I could get cloth and cut in stripes, then plaster of paris, add water, and drag the cloth through that. But that dries in what, 20 min? The plaster would dry before I could use it all. Is it easy to do small batches at a time? Or could I impregnate some fabric with dry plaster? Then I could do a huge amount, and then only add them to water as I need them? Any other ideas?

[eepster]

Plaster is pretty heavy and kind of brittle, it would not be my first choice of material. What are the detail of the sculpture? Where will it be displayed? Does it need to be archival? Will it be painted or left to show the surface?

Possible alternative mediums that come to mind are:

• papier mache, easy to work with and light, but not archival at all
• fiberglass, very durable and light, but major pain to work with
• paper pulp, can achive a huge range of effects, but takes practice with the medium

These are just a few off the top of my head, if you could give us an idea of what the sculpture needs and what you have to work with, then we can probably help more.

[AllisonR]

eepster, thanks for the thoughts. The sulpture would be a sort of repeating pattern, with deep 6-9 inch ridges and groves, but the actual pieces a bit rough and not super detailed. I thought plaster, not poured, but in cloth or bandage, would be more like papier mache, but of a better, more archival quality??? Maybe not? Would it still be weak, brittle if cloth is dipped in the plaster and that is used? I'd like something reasonably long-lasting, but doesn't need to be 3000 years.

I've never worked with fiberglass.

I am very into paper, and have some large (3 foot x 3 foot) paper sculptures on a mesh background. I'd love to do it in paper because I know it would work and I am comfortable with it. But I thought for this project that the risk of damage is too high with paper. Someone accidentally spills water and it is all over. With something 7 foot x 7 foot and all paper (or mostly paper with a hidden mesh frame underneath), if it falls to the ground it could easily break.... Most of it needs to be white, off-white or natural, with a small section in color - which I can either paint on the surface or use a different medium for.

Does this help? What do you think?

[eepster]

Since you have worked with paper then I would recommend heavily beaten flax. When the pupl dries it is extremely hard. If you can get your hands on the equipment and materials it should be perfect.

You will need the flax, this is most easily obtained as flax tow or line for spinning (tow is usually cheaper and fine for this purpose.) You will also need access to a hollander beater.

First the flax needs to be cut into short pieces around a half an inch or a centimeter. A rotary cutter like quilters use is easier on your hands than scissors. Then the flax needs to soak at least 24 hrs, longer is better. Finally it must be beaten in the hollander beater for 9 hrs or more. The roller should be gradually lowered till it is at the lowest setting the beater will allow. When it is done the pulp has an almost clay like feel.

When the pulp is ready it can be formed into sheets which you can place on to a form and weight, or it can be sprayed onto mesh. You can treat it pretty much like you would with any paper pulp, except that as it dries it will shrink incredibly if not held in place, and it will become very hard and durable.

[PreggieUBA2C]

nak

Could you do the piece in pieces? Sheets of copper foil could work, but of course, you'd have to sculpt each part individually and then fasten it all together (I love working this way). You could use a white patina to change the surface colour of the copper. I found some copper here http://stores.ebay.ca/Nimrod-Hall-Co...QQftidZ2QQtZkm but didn't search for price comparisons.

It just occurred to me that I could do copper tooling right at the kitchen table, with the littles doing their own, and it would be safe (with edges rolled, of course)! I'm thinking of it...

[TeaLeaf]

To work with plaster, use small batches in a basketball into which you cut a hole at the top. It's easily cleaned by just crumpling the ball; plaster doesn't cling to the rubber and you'll save your plumbing.

Here is a place that tells you how to mix the plaster: http://www.wikihow.com/Mix-Plaster-for-Sculpture

Prepare cheesecloth strips that you can dip into the plaster and apply to your form. You can buy the cheesecloth at any hardware place in the painting department usually or car cleaning section sometimes.

You may have to use an extra batch to put on the form at the end to smooth things out. Use rasps to shape. That's cheaper than the rolls you buy. Messier and it will take practice but it works

Another technique would be white cement; use fine metal wool you find at boat places, not the steel one that will rust. The boat wool has copper in it, I forgot, and won't rust. You apply the wool to the piece and put the cement on it. Cement doesn't dry as fast as plaster. Use rasp and sand paper before cement sets to shape/smooth; you'll know when it's hard enough. Cover the piece with garbage bag until set, so it doesn't crack

[AllisonR]

Thanks for all the tips ladies. I thought I would go the handmade paper route - but that has turned way to complex and time intensive. The amount of paper I would need is obscene. So plaster is probably the way to go, but that is not necessarily easier. There is the question of pigments, which can weaken plaster; the question of strengthening the plater (which could be bone emulsion, elmers glue(which doesn't exist here) or using stone cut plaster instead of alabaster plaster, or ???); and the question of extending the drying time (which now is 30 min for alabaster plaster, and only 12 min for stone cut plaster with cold water)..... Testing, testing, testing....

[TeaLeaf]

elmers glue is just a white water base glue used by kids for paper projects; i bet you have something similar.

instead of mixing the pigments, why don't you stain the plaster or paint it? you can really get neat reasults, make it look like stone for ex.

[AllisonR]

Originally Posted by TeaLeaf

To work with plaster, use small batches in a basketball into which you cut a hole at the top. It's easily cleaned by just crumpling the ball; plaster doesn't cling to the rubber and you'll save your plumbing.

Brilliant tip. Thanks!