I was watching a wood finishing video on YouTube and saw this MinWax Pre-stain Wood Conditioner demonstrated. It was painted onto a bare wood surface before staining to hide uneven and blotchy wood grain.
After it dried several hours the MinWax finishing stain went on smooth. It showed the wood grain but not the imperfections.
I thought this might be worth a try on several, to be scratchbuilt, basswood structures. I planned to age by staining the wood. I bought a can and it works well. I still need to experiment more but it does what it says by hiding the funky grain and discoloring that basswood has.
I've also tried it to seal plaster castings and have painted it over a finished structure to seal and protect the paint and weathering.
Be aware that this stuff is thin, like water, is solvent based so you need an overnight drying period, and you clean your brushes in mineral spirits.