Hi Michelle I think if you post this over in the hypertufa forum you may get more feedback.I have generally used blocks of styrafoam, cut them as close as possible and used duct tape to hold them together. The expanding foam would cost way more than the pieces, especially if you recycle some already around. Chicken wire makes me a bit nervous as an armature depending on the size of your sculpture, I use hardwarecloth for larger items,usually combined with rebar, it is so much stronger, if your armature isnt pretty solid it will have some challenges.I usually make my own mixes, so dont use commercial mixes too often, but would not recommend the quick crete with a fibre additive, I think the acrylic mix with added fibres would be a better choice. How large is this sculpture, and do you have previous experience with concrete? A really awesome book with great how to info is called Making concrete garden ornaments, by Sherri Warner Hunter, great info on building armitures, and all kind of mixes. Hope this helps a bit. Cindy

Thanks for the consult and the tip on the hypertufa forum, I didn't realize that there was one.

I do have experience with very large 2 dimensional sculptural pcs. and to an extent some moderately large architectural ceramic work ( human scale '+' ) but not large 3D work done with concrete as an armature for mosaic application.

The reptile is about 8 feet long and if you are familiar with Antonio Gaudi's reptile fountain at Guell Park , it is somewhat similar in scale.

Thanks also on the tip of Sherri Warner Hunters' book, I remember checking it out a year or two ago at the local library , guess I need to recheck it out. Sounds like it might give me some good tips on mixes .

Thanks again.

Michelle,

Cindy has some great suggestions. I've sent you an email with another.

Thanks Lazydaisy !
I only had a minute to check out the wet canvas site , but will revisit it again tonight.
It looked very informative.

Thanks again

Please be aware that expanding foam may continue to expand if it gets very warm, a fact that might crack your surface concrete.

If you use block foam you want to build up, use carpenter's wood glue or Hornweld concrete additive: slap some non-diluted of either on both surfaces of the foam (it can be just thin layers), let it set a few minutes, then press the two pieces together.

Another product that attaches foam to foam is Foam Panel Adhesive (for use with caulking gun), but you have to leave it overnight, preferably weighted. I'm usually too impatient for that....

'Pup