help with background please

[arielgasca420]

I failed at making my first background out of plexiglass, great stuff, and silicone. It turned out that the topsoil I used on the background came off the silicone, due to moisture, and let out a faint chemical smell. the background has only been in there for three days and I took it out to let it air dry for inspection tomorrow morning.
However, I have changed my mind on the background and would like to use bricks. would silicone be a good adhesive for a porous surface, such as bricks, or should I use a different adhesive? I do have a glue gun, but I am unsure of that method. any tips or advice would be good. thanks for reading

[arielgasca420]

decided to use gorilla glue from reading other forums saying to use the kind that dries white. does anyone know anymore product information on this white glue?
the only thing I have found is gorilla glue 5201204 glue dries white. just want to double check before I buy it

[DonLisk]

When you did the background how long did you allow the Great Stuff to cure before adding the silicone on top and then putting your soil to the silicone.

Gorilla Glue dries permanent and if you make mistakes it is not going to come off I believe. It is also almost impossible to sculpt it once dry but anything it touchs such as your hands, accents, glass, is not going to be easy to remove if accidents occur while applying it.

As for smell, the GE Silicone 1 product needs to air our for quite some time since the smell sticks around for a week but GE Silicone II usually has the smell mostly gone after about 4 days with good air circulation.

Great Stuff should be allowed to dry completely so if you put it on really thick it will take more than a few days to completely dry inside the deeper sections. I puncture holes to help with drying and allow for the still expanding areas to release anything trapped under the already cured top skin.


If attaching bricks (sounds heavy) a glue gun isn't a good idea since it separates from Plexi and glass fairly easily.
100 Percent silicone is good as would be the Gorilla Glue, or even a little bit of the Great Stuff can be used to attach the accent items.


Take your time, give things time to dry and air out, before moving on to the next process when applying anything that has to cure.

[arielgasca420]

Thanks for your reply don, i did want to clarify a few things though. I let the great stuff sit in my garage for 6 days before adding silicone and let the silicone sit for 3 days(opened the garage a bit) I did use a small amout of acrylic paint to touch up some spots that i missed and i have a feeling that is where the smell came from. I thougt the brand was VOC free but i will double check the can. I will most likely get some more silicone and silicone over the places i used the paint.
As for the bricks i need something for them to adhere to one another and then attach the bricks to the glass with silicone.
I do not want to trash my first background because i spent a lot of time on it. Its possible that i can still use it in my bearded dragon cage. Is there a safe brown colored silicone i can use?
Thanks for your help

[arielgasca420]

I almost forgot to mention i put the soil on as i applied the silicone. I did it section by section. The silicone was so hard to get into all the cracks so i had some yellow spots showing through when i was done. I probably should have used two bottles of silicone

[arielgasca420]

So I have been looking around for brown silicone and I have come across the following item. I would like to know if it is safe
GE Silicone II Brown Silicone for Window and Door Caulk
I understand there is brown pond sealer but that stuff is a little too expensive for one small project. I would be more favorable to buy it if I had a few several projects to use it on.