I often have to decant thinned sanding sealer into jars at work, but would never consider doing it at home.
I basically do a 60/40 mix in one of the tins it is supplied in, and add extra thinners over time if needed.
I only apply sealer with a brush if I'm working on "punky wood" between cuts to help with the removal of tear out, otherwise it is applied with kitchen towel, near the final outcome to spot any hidden defects. I only use Cellulose by the way.
Metal on metal threads will usually be unglued by a quick shake of the can.