I like to thin my polyurethane finish with mineral spirits as an alternative to buying a wipe on poly - but when I started to look at several of the easily available options for Clear Gloss, like Varathane or Minwax or Arm-r-seal, their MDS sheets show a huge range of total solvents, in each product, like they cant (or wont) tell what’s in each can.
Here’s Minwax Gloss Poly which I think of as a “full strength” (and seems thicker than Arm r seal, for instance):
Ingredient name % by weight
Light Aliphatic Hydrocarbon ≥50 - ≤75 (other ingredients listed are each less than 1%, no listing of polyurethane or resin or anything.) So, 50-75% solvent - quite a range there!
Here’s ArmRSeal which I think is more a wipe-on poly, fairly thin out of the can:
Chemical Name (3 separate listings with different CAS#s called mineral spirits)
Mineral spirits 20-40%; Mineral spirits 10-20%; Mineral spirits 5-10%; Nonane 5-10%; Oil modified urethane resin 10-35%; Resin 0-25%.
(Nice they give at least a mention of resins, but again, ridiculous ranges! 40-80% solvents, 0-25% resin etc)
Varathane Gloss showed similar large ranges.
Why don’t these companies a)know or b)have to put better estimates of total solvents? I’m a newbie but have read enough online at least, to have absorbed that finishing products are mostly unregulated, buyer-beware, no way to find out what is in them (eg Danish Oil). Is there any way to know which is more concentrated, except by how thick it pours out of the can? Frustrating!
Anybody with the inside track, on this?