DIY rock formation gone wrong - Help

[Trajega]

Not @ home, so I cant supply pictures. Here is what I did:
Made a series of u shaped insulation stacked together with glue and put a square piece on the top. It is probably 20 inches by 19 inches by 5 inches tall.
Then used a paint sponge to spread unsanded grout across the entire surface.
The grout was mixed probably 1 part water 2 parts mix.
Most of the surfaces are smooth after the painting, but some of the grout pooled on the inside of the steps to the pyramid. I notice mine does not have all the little grooves like other pictures shared.
After 1 full layer, I put it in with my dragon. Now it is chipping and falling apart, also Jelly likes to leave her waste on the top of the 'step pyramid' and it wont rinse off very well, i tried scrubbing, but this caused cracks across the top surface.

I am thinking its not worth salvaging, including the dimentions do not work for Jelly's home, so would like to know if anybody can tell me what I did wrong when I go to take a second stab at it.

 

[doe222]

gotta do more than just 1 layer of sponged grouting. what you wanna do is use a brush and generously put on a thick layer of thinned out grouting. than do another layer of semi thicker grouting than another. than paint it (i used rustolem rock paint looks really good ) than goto hobby lobby and buy some mod podge. put on 3-4 coats of that, put them on kind thin or else it will make it look shiny. make sure you get the MATTE mod podge and not the gloss. You want the grouting to be thin enough almost like a water. i actually used plaster of parris because it only takes 30min to dry. if you want more tips send me a msg. ill give u pics of mine.

 

[Claudiusx]

Did you seal it at all?

I agree you need to put more layers of grout than just 1. And once you are done grouting you have to seal it.

-Brandon

 

[doe222]

the sealing is kind of a big deal definetly, thats why instead of grout i just used plaster of paris. which i definetly recomend next time. you can buy a big fat bag of it for 15$ and it dries pretty fast 30min u can do another coat. and its also a hell of a light lighter. just make it nice n soupy dont follow the mixture directions. the BEST thing IMO to seal it with is modpodge as long as your not like trying to make a waterfall or anything. i did a full DIY setup for my comparable to 130gallon tank so ive been there done that i only did one coat of sealer and it started to flake so i did like 3 more. and the paint also helps seal it as well but it may be toxic. the rustoleum rock paint also adds grip but you sprinkle sand onto the sealer to do that as well.

 

[Trajega]

plaster paris sounds good, although Ill have to debate it when i already have a Huge thing of grout. I think I discovered another big issue:

WHat is this sealing thing you speak of? I made sure the coating was full and airtight, doesnt that seal it up? Given that it went right over my head tells me this is just as big of a deal as only using 1 layer.

 

[Claudiusx]

You have to seal over the grout... With an actual sealant, such as modpodge.

Otherwise it will just crumble away.

-Brandon

 

[doe222]

see i got the base of my ideas and how tos from lizard-landscapes.com
You seal it so its semi waterproof and so your beardie doesnt injest anything toxic. Modpodge is pretty much non toxic glue it is white when applied but dries clear. and you just cover everything in it to seal it. and if u got a bunch of grout just grout it. plaster if paris was just an idea. your thing is definetly salvagable. just take it do another 2 coats on top of it JUST to make sure. than goto the store, walmart was the cheapest i found and buy some paint. Rustoleum has textured paint. http://www.walmart.com/ip/Rust-Oleum-Multicolor-Textured-Spray-Dessert-Bisque/17011107 depending on how big it is you may need 2-3 cans of paint. for however many cans of paint you use id recomend a bottle of mod podge. get a paintbrush and just start coating all the painqt with the modpodge. do multiple thin layers. if you do thick layers it will shine. MAKE SURE YOU GET THE MATTE. the gloss with shine and look dumb. If your sculpture is too big try knocking the grout that you have on there off and cutting the foam down. a good rule of them is a quater inch extra space on each side before adding grout and paint and sealant. make sure the paint is dry before sealing it. but the sealant just make sure its semi dry. you can tell cuz it wont be white anymore.

 

[Kajolic]

Word of caution on spray paint. Be sure to do light coat(s), DO NOT spray it heavy. It WILL soak through to grout, and dissolve your styrofoam. Happened to me, but was salvageable with re-grouting. Assure you have no thin spots of grout (areas you did 1-2 layers and forgot to go back over) because even a light coat of spray paint till soak through to the styrofoam and dissolve it away.

Wanted to add, the rock textured paint he suggested does look wonderful! I ended up not using my faux rocks, instead using real slate, but I still loved my results with the rock textured paint. I will suggest, there are several colors to pick from. When I did mine, I used the one he suggested, as well as the lighter one to give edge accents to the rock to appear more worn in areas. With patience, and enough grout to the paint doesn't soak through as easily, the results will look amazing.

 

[doe222]

the textured paint i didnt have a problem with soaking through, but i used plater of paris thats made for painting so idk if theres a difference there. i dont think you rlly gotta worry about it with the textured, i laid it on real thick because its not really like coatable. it is but it lays down different than regular paint it shoots little rocks out , you could always throw down a thin coat of sealant. give it a fast rub with some sand paper to rough it up and than paint if you were worried about it.

 

[Kajolic]

Spray paint is spray paint regardless of just plain paint, or the rock texture style. Unless it's water based spray paint. Otherwise the solvents in regular spray paint will dissolve the styrofoam if it soaks through a thin layer of grout/a crack, and it will spread.

This was from a small crack in the grout from moving the piece around, that I failed to notice prior to spraying.
Note how it expanded from a crack out quite a bit. This was uncovered as I
pressed my finger through the grout to see to total damage:

Here is an example of thin grout that allowed it to soak through:

You did bring up a good suggestion with a thin layer of sealant prior to spray painting. I thought of that after the damage, and actually tried it out on a test piece, and it seemed to work.

Don't do this, but I tried it out on wet grout and spraying the paint with the grout wet, even though it was a thin layer, since the grout was wet already, the solvent did not soak through. Thought that was fairly interesting.

I wish I would have, in my case, used Shields-All prior to the spray paint. Although in the end I salvaged the faux rocks, I didn't even use them. Granted they looked awesome and spent a long while doing them.