Originally Posted by astride13
I didn't even need any silicone to seal. It depends on how smooth your cuts are.
very good point!
it is critical that your edges be completely smooth and even ... a friend recommened to me laying a sheet of sand-paper on a table, and then passing the cut along the sheet, back and forth until it was smooth and even - this helps keep it from getting crooked, which can happen with hand sanding. the tip works very well!
also, incase you've got something that's just not fitting right, Weld-On is also available in a #16 gell, which fills small gaps and still provides an extremely strong bond.