how do I make rock wall?

I want to make my room's wall or maybe just a part of a wall look like rock (lava rock?). Then carve hawaiian petroglyphs on it.

What is the cheapest, easiest way I can go about it? I don't own any "man tools" and I've never done any craft. I did a search on the web for 'how to make fake stone' but it sounds too complicated FOR ME with all those chicken wire and grout mixing.

I was thinking of using styrofoam sheets, then carve my symbols with a 'soldering iron'? Then paint it with those stone spray paint.

Now the problem is, the styrofoam sheets would be too nice and FLAt. How do I make it more 3d like a cave wall??

I read some where about some insulation foam. Can I spray this foam on top of the styrofoam sheet?

Thanks for any idea.

Spray foam is junk, IMHO. Good for insulating around windows.
Much better stuff available.
High density urethane foam would be ideal, but expensive.

Styrofoam can be laminated, then carved.
Blue foam has a tighter texture than the white.
Regular white glue works, solvent based glues eat the less expensive foam.
Coarse sand paper and sharp knives work on foam for shaping.

Someone might be able to suggest a better material.

[ Edited by: Unkl Ian 2009-11-10 21:21 ]

[ Edited by: Unkl Ian 2009-11-10 21:22 ]

I'm looking to do a bit of the same thing in my tiki room, and I wasn't gonna tell anyone this until I was done, 'cause I'm not sure what the results will be...

...I asked a friend/co-worker of mine who works on movie sets how she would make a fake lava wall. Since I'm not doing a waterfall/feature with the wall, She suggested using styrofoam.

1. Carve the styrofoam (this is probably the hardest step, and the one that would take the most artistry)
2. Coat it in 3 layers of white glue. Yes, that's kid's school glue.
3. Once the glue is dry, Liberally coat the foam with Spackle or drywall mud.
4. The next part I came up with by reading threads here on TC; take a corn broom and texture the wet Spackle with it by using the bristle ends as a stamp. Make other holes with other round objects.
5. Once it's dry, paint it.

I did do a small test piece and it looks great. It will be quite a while before I'm finished. I'm not sure of the durability...so you may only want to consider this method if your wall will be out of most folk's reach.

Take lots of progress shots no matter what you end up doing.

i've done this type of work before. you can get sheet foam and carve it. the best tool to do that would be a small wire brush and a thin blade utility knife. once it's carved you can coat it with a hard coat. you can get something at micheal's yourself, or have it done at a local foam architectural company. you can also have it done at a place that sprays on bedliners for pickups. any hard coat that wont eat the foam away will work. you'll need to apply the foam to a board as a substrate to keep it firm. you can use luan, it's pretty cheap and will work well. use 3M super 74 (i think, make sure it's the stuff made for foam as super 77 will dissolve the foam) or contact cement (water based).

use a sharpie to draw your pattern on it and have fun. you can make rocks, petroglyphs, transluscent areas with back lights (use rope light as it gives off no heat), hand prints, kids sigs and anything you can think of.

the more dense the foam you get the better it will carve. almost all foam will sand down pretty good. use a wood rasp and about 120 grit paper to get it to the point that it will look great. you'll figure out how to get the detail once you start to work with it.

it really does become fun and you get used to it pretty quick. it does make a mess. put down a cheapie plastic drop cloth to aide in cleanup or use the shop vac. if you do it outside, beware the wind. sometimes a dust mask is a good thing, too.

good luck.

(oh, put screw holes in inconspicuous places to screw it to the walls with sheet rock screws. it wont take many.)

most architectural foam places sell the sheets in different thicknesses pretty cheap. if you don't have a truck, no problem. get them 2' X 2' and reassemble when you get home with the spray mount or elmer's glue.

[ Edited by: pdrake 2009-11-10 22:05 ]

[ Edited by: pdrake 2009-11-10 22:10 ]

don't, don't, don't use a soldering iron. (just reread your initial post.)

PCVs are extremely carcinogenic, plus you'll gunk up the soldering iron.

you can get by with a kitchen butter knife if you have to. scrape, scrape, scrape, then sand. no man tools required. you should be able to do it with kid tools. maybe a pumpkin carving set. seriously.

surfshack, welcome to TC. Looks like you've got some good suggestions here to start. I've played with foam some so here's my 2 cents worth:

You can start with a sheet of 1 inch foam on plywood, then add irregular shaped pieces of 2 inch foam to get the 3D effect

White glue can be problematic when laminating large sheets of foam since air doesn't reach the center and the glue doesn't dry. I use Gorilla Glue, it uses moisture to cure the glue. You mist the foam lightly with water before you glue it, "damp it and clamp it" they say. I also use short pieces of bamboo skewers or toothpicks to pin the foam in place while the glue sets, if you push the skewers in flush with the surface of the foam you can just leave them there. Be sure to use gloves and drop cloths when working with Gorilla Glue, it doesn't wash off - EVER!

There are some commercially available coatings like Vanillacryl or "Steve's Coating for Styrofoam" but I haven't tried them because they are expensive and I am cheap :) You can mix up "Monster Mud" to coat foam with. 4 parts premixed wallboard compound and 1 part latex paint. Mix well and apply to the foam. I have also mixed small gravel in with the Monster Mud to add texture. After it dries, paint it well with latex paint. You can't use spray paint on foam because it eats the foam, but after a good coat of Monster Mud and latex paint, you can use spray paint for an "airbrush effect" for shadows and highlights. All of my foam projects have been temporary, I can't say how Monster Mud would hold up for a permanent project.

You best bet is to experiment with a small section before you build a huge wall. Here are some samples of my foam work in case you get bored :D

Hi Surfshack, the things you can make with foam are endless, I have had Good luck using both spray foam and sheets of pink insulation foam you can purchase at any home supply store, Mikes got a Great site for foam use and you can also check my site out for some more ideas on this at http://www.Eyeballjohn.com, foam can be carved with anything you have laying around, sand paper, wire brush your fingers, once you get the look you want coat the foam with a sealer even hose paint works, then paint your finish coat, once you get the hang of it it's not hard, here are a few pics of what I did with foam, Good Luck, John

Holy smoke! So many great ideas straight from the pros, and even some tips from a movie-set worker too.
This place Rocks :P Thanks guys :D

Slack Ferret: How about a sneak peek at what you have so far? :P

Pdrake: Thanks for stopping me on time. Else I woulda be buried under piles of unfinished rocks.

um . . . okay? glad you're okay, hope the lava foam is going great and you're having fun with it.

thanks!

oh, by the way, i was fortunate enough to spend time hiking around the area that has all those petroglyphs. it's an incredibly amazing place. well worth the stop and hike. i was able to take some great photos, too.