Make a Fake Rock Cave/basking Spot for a Reptile Cage.





Introduction: Make a Fake Rock Cave/basking Spot for a Reptile Cage.

Here I'll show you how to make a fake rock cave/basking spot for your reptile cage. This is one I've made for my Bearded Dragon, Viggo.

Step 1: Design!

This is my original design I made months ago. The design has changed since then, but this illustrates the basic concept of what I wanted to make. A large cave, with a door allowing access to it from the outside, a basking spot above, and a ramp going up. PLAN AHEAD. I can't stress this enough. It will make things much easier for you. I've used Google SketchUp to render this 3-D model. Google SketchUp is a great FREE architectural 3-D design program. I'd consider this (or a similar program which may not be free) to be an essential tool for any craftsman/designer/builder. You can download the program here,
Google SketchUp Download

Step 2: Gather Materials and Tools.

Styrofoam ~ Free (This is trash, you can find it for free. It's used to pack all sorts of things. Try going to the back of an electronics store and asking if they've got any you can save from the landfills. I used a broken styrofoam cooler and some odd packing bits.)
Grout mix ~ $8.98 (I got a carton of Sanded grout mix in HEMP color. The sanded leaves a rougher texture than unsanded. The hemp is a kinda dark gray color that already looks like rock. It gives a nice dark base color and could be used without coloration if you want)
Cement Color ~ $4.96 (I used Terra Cotta. Mixed with the Hemp grout it gave a nice red rock color. This is a liquid color mix. You can also use powdered grout color mix. It's about a buck cheaper, but they were out of the color I wanted.)
Great Stuff Expanding Foam Insulator ~ $5.00 (Trust me, this stuff will make things much easier and is well worth it)
Water ~ (To mix the grout)
Water Based Polycrylic Satin Sealer (Go for Satin, not as shiny as gloss and gives a more natural look. You'll need enough for 3 coats. A small can will probably suffice. )

Knives and hand saws (to cut styrofoam and shape your cave)
Hot Glue Gun and glue sticks (works great for gluing pieces together and it's safe. DO NOT USE SUPERGLUE. Superglue, or other such chemical glues will melt/eat through styrofoam and give of toxic fumes)
Bucket (For mixing grout in)
2 Cheap Bristle Paint brushes (One for applying grout, one for sealer)

Step 3: Start Building!

The best advice I can give you here is to actually work inside your viv. This helps you make sure it will fit, as well as gives you an idea of proportions. You wouldn't want to accidentally make it too large. Remember to leave some extra room around the edges. You don't want it to be a tight fit now because you still have to grout it.

Start with a real rough cut, just laying things out. Don't glue anything down yet. It also helps if you can draw on the floors and wall of the viv to give yourself reference points for shape. If you don't actually want to mark your floor, lay down some newspaper you can draw on)

Get your basic shape together. Don't worry about leaving holes and don't do any detail carving yet.

Step 4: Glue

In order to get everything back the way you have it now, it really helps if you draw marks and lines onto your shape. Trace the outline of a piece onto the piece below it. Trace the bottom footprint onto the bottom of your viv or newspaper. Take off each layer and start gluing things down working from the bottom up (don't glue it to the floor!)

Step 5: Expanding Foam!

This stuff is truly great. I guess that's why they call it "GREAT STUFF"
Spray it in to fill in all those little holes and gaps.
Use a little more in places you want it to build up.
Leave it to expand and dry overnight.

Step 6: CARVING!

Pull out your knife and saw and go to town! Time to get creative and let your artistic side show. What you're carving now will be the shape of the final piece. Remember, don't go into too fine detail. The layers of grout will fill in a lot of the small stuff completely. If you want it to show up, cut it deeper!

Step 7: Grout!

Ok now, time make this look like a rock, and not a big chunk of foam.
Mix your grout. Don't mix it all at once. Leftovers will dry out while you're waiting between coats. Try using about 1/4 of your grout per coat. I don't really have a set measurement for water, but you want it to be kinda thin and soupy. It will brush on easier that way. If you're using coloration, this would be the time to mix it in.
Once you've got your soupy grout, start brushing it on.
Make sure you get in all the cracks and crevasses, including the bottom.

Let it dry overnight between coats.

Apply 3 coats! This will ensure everything is covered and it will be nice and strong.

Step 8: Paint!

I didn't paint mine, just used the cement color, but if you're gonna do that, now would be the time. Acrylic works best I hear.

Step 9: Seal It.

This is a very important step. Use a safe, low fume sealer such as Water Based Polycrylic sealer if possible. Shellac also works well but will leave it shiny. I actually ran out of polycrylic so I used shellac inside the cave and on the bottom where it wouldn't be seen.
Use your other brush and apply 3 coats of sealant, once again, making sure to get into every crack and crevasse. Sorry, no pictures here, cause there's not much to see while sealing. Once you've finished, let it air out for a few days, preferably with a fan blowing on it.

Step 10: Enjoy!

Well, this step isn't so much for you as it is for your dragon, but hey, you can still sit back and enjoy looking at your handiwork.



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If anyone likes my terrarium, I made the rocks from 1 sollid peace of foam , carved everything out and coverd it with epoxy mixed with sand.
Then airbrushed it and and the background is just a nice air-picture covered with glass ...

2 replies

That's awesome! what breed of lizard is that?


Like It? I Love It!
If only I could make something like that.

I just want you to know that I am in the process of making this and it is coming out fantastic! I will post photos soon.

Nice idea! and all the things are safe for pets I'm assuming?

i have a 2 mos old leopard gecko. i want t make a hiding cavern all along the back of the tank. just so it's one piece. but long enough to have a hiding spot in the hot spot and cool spot. have you done something like that?

this is so unique i love the way you made this product

I like youre design !!

Here's something i made with fome and epoxy...

3 replies

Magnum kids- I have a question for you about your amazing rock installation. I hope you're still active on this site....

Magnunkai* sorry auto correct

Hi Magnumkai , your cages are beautiful do you have a step by step instructions on how to do this ?



I made a fake rock but having issues. Its cracking. It took a few weeks to make. I thought it was ok but now that its been in the tank the whole under side is cracking. Im going to have to replace it now but should i be worried about fumes....

How many gallons is your tank ????

hey man awesome job just wondering if this is water proof i want to make a water fall for my red tail boa out of the same stuff

2 replies

making an aztec temple for my redtail it works well, and if you use the clear silicon (pasti dip) it will waterproof it. (using that ontop of the joint compound because i want to seal down the moss im putting on mine so my snake doesnt pull it off :) )

Do you have an instruct able on it? Sounds cool! :)

would this be hard enough so that the lizard isn't tearing at it and able to eat the pieces?

So I already have a bag of unsanded grout at my house. Can I just use that, or should I buy a bag of sanded grout? The unsanded grout is a coco color, and I think it should work, but I dont know....

Did your spray foam crack too?

Stay away from spray paints on this step (or be super sure everything is covered in grout)! When I did it, invisible gaps in the grout allowed some paint to get through and it ate away the styrofoam underneath causing the grout to crack and fall off (not to mention the super toxic fumes it probably made).

I have a couple questions regarding hydraulic cement;

First,is it hudraulic cement waterproof? I wanted to make a shallow pool for my 3-toed box turtle, so I would need it to hold water. If not I can seal it with a coating of silicone where the water will be sitting.

Second, I am making this roughly 10" wide by 22" long and a sloping 4" to 6"deep ith a section for a filter/waterfall (the deeper part). This means I will have to cover my styrofoam mold with the cement in parts-will the sections of cement bond with each other? I don't think, well I know I can't put cement over the whole thing before it starts to set on me, so I will have to do it in sections if I decide to go this route.

Third, can you color hydraulic cement, and if so how? I don't want to paint it as the whole purpose of using the cement versus grout is the fact that I don't have to seal it with expensive nontoxic sealants or possibly toxic and high VOC acryllic products. Nor do I want to have to wait the 7 hours between the multiple layers of grout, then applying sand texture and painting and sealing and finally applying the silicone. It could take over a month of weekends to get this done that way, plus the extra cure time for the water resistant sealant and the silicone.

I was thinking that with the cement it would take me 2 weekends, one for the molding, and another for the cement. Possibly another day for the silicone and then a week to cure it before my turtle could get to use it.

Thank you for your help with this, I am eager to give it a try.