There was a post awhile back about dealing with varnish jelling up in the can or container, but I don't remember anyone with a solution to its prevention other than allowing a little propane to enter the container somehow.  I just opened a brand new  (albeit a year-old un opened) can of Interlux Satin Varnish for the final coats on my Skerry interior and spars, and the amount of jelly, (read that waste) seems too much for me to to have to contend with.  Once the can is opened it seems to get worse and more wasteful.  I learned this with the first four coats of Interlux High Closs varnish.  How about some ground rules?  I have poured unused varnish back in the can from a plastic cup.  I guess this is a no no?  What about transferring everything from a newly opened can into a clean glass jar with a twist top?  I tend to hammer down the can lids too much to the point that the can caves in at the top yielding a poor seal.  Dumber question:  can the jelly be thinned for use or is it just considered one of the downsides of working with Marine varnish at thirty bucks a quart?  Any help or suggestions appreciated.  Also does the formation of jelly mean the varnish itself is compromised and can the remaining liquid be used safely??  best,  bob h.