Love the idea. You could do both sides of the butterfly. We have experts on using Wedi board here. I hope they chime in!
Kathy

Oh Yes! Wedi board would be great for this, but also I could see using a cement board too. You can get that at any local home hardware store. Also I could see using styrofoam, carved/sheets, and last but not least, wire mesh formed into shape and cemented. Styrofoam could be used by using a paintbrush and mortar, then a layer of drywall tape, then mortar again, attaching it to the pole is the tricky part...hmmm, poking a hole and then using some kind of mighty putty?

So, it looks like I could get Wedi board in 1/2" thickness. That would be thick enough to poke a thin steel rod through for my post. I'm thinking maybe along the top (where the rod would be in danger of poking all the way through), I could reinforce the edge with a thin, bendable strip of sheet metal secured with....duct tape?...drywall tape? Would I have to then cover the whole thing with wire mesh and cement it all over before I mosaic?

OR I could get two 1/4" pieces and glue them together with the rod sandwiched in between.....?

I've never used cement board on a project. Can I just thinset my pieces right onto it, or does it need some additional sealant?

And I'm gathering by the responses, it's true that even 3/4" plywood would ultimately fall apart in the weather? That would be the easiest solution as far as figuring out how to secure the rod goes. Is it not possible to seal plywood well enough to stand up to the weather?

I swear, I've got 4 books on mosaic, and none of them have exactly the project I'm looking for! LOL I very much appreciate your helping me brainstorm this!

Never use plywood for exterior purposes. If I were to make this project, I'd use either the cement board or the hardware cloth/mortar technique. Drill holes into the cement board to wire to your rod - wear a mask. W/the HC/M method, it w/be easy to use your stitching wire to wire the armature to your steel rod. The mortar comes in 40-lb. bags, and the HC comes in rolls - 36" X 10'. You could make lots of small things w/it. Believe me, once you try that method, you'll become addicted to it just like mosaicing.

I know! I would like to give the hardware cloth method of concrete art a try. I'm quite bummed--A class was being held at our local JC on armature sculpture. I went to sign up for it a solid 4 weeks before the class date, and it was filled up! (whaa) I'll admit, I'm a little intimidated to make the switch from cement molds, which was why the class was such a coup. But I don't doubt I'll be hooked once I give it a real try.

I've been studying your castles to see how you do it (it looks really complicated!). I had wanted my little butterflies to be at least a 1/2" thick. In one book I have where the author makes outdoor sculpture using hardware cloth, she creates the shape with styrofoam then secures the cloth to the outside. In another, they just crumble up newspaper and wrap the cloth around it. That's leading me to believe the inside would be pretty water tight once it's done.

Now I'm thinking maybe I could cut the shapes out of plywood to use as fill. I could secure the rod by drilling a hole through the bottom of the plywood. Then wrap the hardware cloth (or maybe a more flexible fiberglass mesh?) around the whole thing and cover it all with mortar.

Do you think that would work?

Your idea of an inside filler is right to use as a form. Remember to put two layers of the hardware cloth around the form. Newspaper is a good and free to use to help keep the mortar from falling through the cloth. The diamond lath holds the mortar so much better than the cloth, but more difficult to form into small things. It's not complicated at all, LORI: For the castle, I just built a box, then cones. The parapet was a long pice of doubled cloth. I measured equal distance along the cloth, bent down one of the distances, then folded the others into the point. I use electrical fencing wire - 17 guage - for stitches. If it w/make it easier for you, cut a paper pattern first, lay it on your cloth, duct tape it down in a few spots, and w/tin snips cut out the shape, allowing allowances for turning down the edges (hemming) so there's no points that w/stick out of the mortar. You can use styrofoam for forms, but it's sorta expensive I think, and an extra expense you don't need. Glad to answer any other questions. Be sure and twist a couple times the stitches w/your lineman pliers, and clip as close to the first stitch as possible - the cleaner your armature is, the easier it is to apply the mortar. I also forgot to mention to sift the mortar mix so the surface is smoother. I also use a wet paint brush to smooth it further.

Thanks so much for the suggestions and advice! I really appreciate the help.

I'm sure you've probably posted it before, but do you have a recipe for your mortar?

When I was making my own mortar, I used three parts sand to one part Portland cement - maybe a little more cement to make it a tad stronger. Once I used up all the Portland cement, I decided it's easier for me to use the Quikcrete Mortar Mix, cuz the Portland comes in 96-lb bags. It had to sit in My Jeep until my yardman w/take it out and put the bag into my garage. It's just too much for my purposes. The Mortar Mix comes in 40-lb bags (there's a bag in the Jeep now waiting for my yardman), and I sift it and add water - in a wheelbarrow/hoe. Use a little water in the beginning, working up to a nice consistency that you can pick up w/gloved hand and make a nice soft ball - not too wet and not too dry - crumbly. Keep adding water a little at a time, mix thoroughly b/f you add more water. You'll get the hang of it w/practice, and b/f long, you'll know just how much to add. It is sooooooooo easy to use this technique w/the wire mesh/mortar, that you'll be quite surprised at the ease. The possibilities are endless. You'll no longer have to look for substrates, forms or moulds - BUILD THEM!!! There's nothing you can't do w/this technique. If you get so confident that you want to build a small bench, chair, table etc., use the diamond lath - cuz it's stronger. Three tools necessary - get the Wiss tin snips, a good linesman's pliers and the 17 - 18 or 19 guage wire for stitches. Put a crook in one end of the wire - making a "needle". Slip the wire into your armature, catch the two layers of mesh, pull out, and w/your pliers catch hold of the end of the little hook and pull it through, twist it and w/the pliers wind it once/twice and viola - a stitch. Repeat until your armature is all put together and you w/be soooooo proud of what you've done. I can't wait for you to try this and report back to us.

Oh, thanks so much for the tips! I've been thinking a garden serpent would be a good armature to start out with, since it starts out as just a tube, LOL. I will definitely give it a try (when this blasted rain stops and I can get back to my garden projects!). When I do, I'll let you know and, of course, post some pics!

A serpent w/be a great piece to begin. You'll have to make a few little cuts and tucks - darts to get the curves, but that's easy as can be. If fact, you've given me a great idea. Might make one too. Hey, we could do one together on here - I'll show WIP pictures, and help you w/yours. I'm so glad you're gonna try this. It's REALLY addicting - be careful. LOL.

Ooh, that would be fun! I've always thought it would be fun on this forum for a few people to attack the same idea and see what we each come up with. I believe someone said you'd done that before. I would love it!