db wrote on Nov 21^st, 2011 at 6:21am:

Does the type of thinner make a difference? Anything better than white gas? If so, why?

While I can't answer questions about long term consequences, I've seen mineral spirits and denatured alcohol listed as solvents for diluting silicone.  Of course, I've seen projects use gasoline for the same purpose, but I don't think I'm going there.

A last question (I hope).  I've read that when sewing a tarp that the stitching should not be too tight, leaving a little give in the seam so the tarp can stretch a little when under a load (e.g., wind).  Any suggestions here?  Would a stitch length of perhaps 1/8th inch be suitable for this purpose?  Longer?  Shorter?

dd