Using polyurethane foam on silicone

[numpty]

Hi there!

I have a terrarium I want to spruce up for a couple of tree frogs, and decided to try using polyurethane foam to add some perches and features.

I thought I'd experiment first, which turned out to be a good decision. A few tutorials had suggested spreading aquarium silicone on the glass first, to help the PU foam stick, but that didn't work out at all as planned. The foam completely failed to adhere to the silicone (which I had left on my test surface for a little over a day), and lifted off it completely as it cured. Any ideas why that would be? An issue with the silicone or the PU foam?

Is there anything I should be looking for as far as ingredients go? (Bear in mind I'm in Taiwan, so brands familiar to US forum users aren't available here). Any techinques or tricks?

Thanks for any suggestions!

[deranged chipmunk]

The silicone isn't really necessary, the foam will adhere to the glass on it's own, but it can help as far as keeping moisture out from behind the foam. You can also just make the perch outside of the tank using the foam, then siliconing the completed assembly in. Or add earth magnets to it with matching ones on the outside to hold it.


Education is the most powerful weapon we can use to change the world ~ Nelson Mandela

[dbizal]

I used silicone on the back of my Viv for Aesthetics mainly... Didn't think there was any other reason to use it haha.

[numpty]

The silicone isn't really necessary, the foam will adhere to the glass on it's own, but it can help as far as keeping moisture out from behind the foam. You can also just make the perch outside of the tank using the foam, then siliconing the completed assembly in. Or add earth magnets to it with matching ones on the outside to hold it.

Thanks for the reply! I guess I'll just squirt a big blob of foam outside the tank, then finish it and stick it back in later.

Any ideas why the foam wasn't adhering to the cured silicone though? I'm just curious as to whether there's something fishy about either the silicone or PU foam. It was acetoxy cure silicone, if that makes any difference.

Thanks again.

[deranged chipmunk]

No clue. Though to even guess without seeing it.


Education is the most powerful weapon we can use to change the world ~ Nelson Mandela