Building a Cave

[UnDeRTaKer313]

we just tried making a cave themed area out of wire mesh and burlap covered with monster mud and it turned out pretty well,it wasnt as strong as i would have liked it to be but all and all looks pretty nice.

[Chambers of Horror]

Matt, I'd love to read that article. I am a home haunter going pro for the first year (2008). I did a short cave entrance last year for my home haunt out of carved foam boards coated and painted. I am looking to do an entire cave maze this year and would love any tips and info you can give.

Thanks

Daniel

[Infoamtek]

Instead of using monster mud, use cement or concrete with a sand aggregate. Much stronger.

[Greg Chrise]

Instead of using monster mud, use cement or concrete with a sand aggregate. Much stronger.

That's what I'm talkin about. Screw Monster Mud!

[Infoamtek]

Screw Monster mud?!? Ewwww! That sounds so kinky and messy. But you're right. Even regular plaster is better than Monster muck. And if you use fiberglass matte cloth with cement or plaster it makes an even stronger material.

[Nightmaretony]

How would be the fire rating to use fiberglass cloth for a cave?

[Greg Chrise]

Generally our caves are cement formulas in either an aliphatic or acrylic resin, spray tectured onto a mesh and rebar frame.

I experimented with taking low grade burlap and coating it like monster mud might be done then hold a torch to it.

The cement and acrylic depending on how thick acts as a natural insulator. It doesn not catch fire but with tremendous continued heat the burlap, untreated would begin to smolder. The solution would be to first dunk the burlap in fire retardant.

In the case of fiberglass cloth, I doubt it would obsorb fire retardent and it would melt. But, the actual test is an open flame for 30 seconds and just having the cement certainly does that. My tests were what happens next to a plumbers torch for a good 10 minutes.

High heat will pop anything realtive to moisture content and heat absorbtion. The ultimate instalation would have a fire retardant in the final sealer on the top coat of the concrete. How it works it as it is heated it is releasing chemicals for some time dispersing any open flame. The result would not be a penetrating heat such as a torch unless you were hit with a fire bomb.

[Infoamtek]

Artificial rocks

Many of the artificial rocks at theme parks and zoos are made from cement/fiberglass/rebar cast from flexible urethane or latex molds taken from real rocks. The molds are powdered with a cement release agent, then a surface coat of cement is sprayed in, followed by layers of fiberglass/cement layups with the rebar set into place. Several different molds are used to keep a natural look. The forms are pieced together like a jigsaw puzzle, welded together, then seamed with cement. When assembled, and the seaming is cured, the rocks are pressure washed to remove the release agent, then painted. A great book to get is "Artificial Rock Waterfalls - Rock Making Techniques For the Professional and the Hobbyist". It is available at http://www.rockandwater.com . They also have a how-to DVD and materials for rock making.

[Greg Chrise]

Fiberglass

Now is this mixed in strands or an actual layer of matting? Strand is no big deal and nearly doubles the strenght but generally would require a final skim coat to hide the strands in the structure.

[Infoamtek]

I rip the matte cloth into 3 to 4 inch pieces and dip them into some fresh mixed cement. I then place them onto the back of the surface layer and press into place, rubbing to smooth out. Also at this layup stage, I like to mix some Acryl 60 into the water for the cement. Makes a stronger bond.

[Greg Chrise]

Hmmmm.

I might have to try this as a sample. I have fiberglass and even refined concrete products and mainly use the Acrylic additives but never put the peanut butter in the chocolate.

This expense wise sounds like THE thing. Burlap is too grainy and nasty, steel mesh is very expensive. Fiberglass mat might be just right.

[Dreamreaper]

Here is a pic of my cave it was done with spray foam.