Quick Question about GS

[Fisherman 1991]

The only time I've ever used GS foam was for insulating, and we used multiple cans at a time. For my 10gal practice tank, if I don't use the whole can, how do I keep the GS from hardening in the straw tube thing? And when you say you do it in layers, how long between layers should I wait?

Thanks again,

fisherman

[froggsong]

Ideally, you should let it cure between layers, at least as long as it says on the can... That way when you carve it, you wont have any shrinkage. I kindof like the way it looks when it shrinks, so I let each layer "skin" before applying the next. I generally let the bottom layer cure a little longer. Personally, I have used a can of GS as later as the third day after opening with no problem, and I didn't do anything but set the can aside. As far as the straw part goes, just take something thin enough to fit inside and push the GS out of the tube. It comes out very easily. In my experience, the GS closest to the can isn't even cured. It seems to work better after sitting for any length of time if you shake it more, like for 75 or so seconds, quite vigorously. I've used it a few times now, and it has pretty much been the same way every time. Be aware if you use the big gap filler that it will expand MUCH more than it looks like it will, especially from the second layer to the last layer. I find that when doing these sort of projects, you get more use out of a can of the big gap filler than you do out of the regular one.

If you want to let each layer fully cure, just let it sit between layers as long as it says to on the can. This still wont be entirely hardened, but at least at that point you wont have to worry about any shrinkage when you carve it after all your layering is done.

[Waterkeeper]

just run a wire hanger through the tube to clear it. it's sticky, but usually not cured.
I too have only gone 3 days with a can...

before I get started I would get a big piece of cardboard and waste a can learning how it works in the wide open.. you can learn to control the expansion with how fast you let it come out, and get a feel for the applicator.. best thing I did was waste a can gettting used to it.

If you want areas that stick out far/shelves (that youknow you will have to layer) you can push in a wooden dowel while it's wet and the dowel will help support the shelves. I have never needed more than 1 layer. I only had to go back and fill small gaps. practice makes perfect i guess

[froggsong]

Instead of actually WASTING a can, you can also do it on top of some wax paper when you practice, and make some landings or hides or whatever and silicone them on later. It is also a good way to practice.