Originally Posted by
Scott T Smith
Julian, I too would suggest a finished thickness of 1-3/4", and no less than 1-1/2". Kitchens tend to be humid so I would also suggest finishing all sides of the countertop with the same number of coats of finish, so as to resist cupping over time.
Additionally I would encourage you to source either single width slabs to make your counters from, or bookmatched narrower slabs that would allow for a single seam.
unlike Wayne I am not a big fan of poly on furniture. A post catalyzed conversion varnish is very water and chemical resistant and would be my first choice unless a glossy appearance was desired. If glossy finish us desired epoxy is the way to go.
Just to clarify, the 2 pack polyurethane I refer to is a specific type of post catalyzed conversion varnish among the many classes of 'varnish available. I avoid using terms like 'varnish' as they are so broad and non-specific as to not convey any accurate information.
For bench tops, polyurethane is an excellent performer. It is available in any gloss level and is highly durable as it is both physically tough and chemical and water resistant.
Cheers
Every construction obeys the laws of physics. Whether we like or understand the result is of no interest to the universe.