I had Noah Stutzman do wheels for my 1912 Hudson a decade ago. Superb quality at a reasonable price! Being cheap, I declined the small extra cost for clear ‘varnish ‘ grade wood. When I picked them up they were so beautiful that I decided that I would NOT paint them. I found that minimal sanding was needed to prep for a varnished finish. They have endured lots of tour abuse including stream crossings and driving in heavy downpours but still look fabulous.
Here is what I did, drawing on my wooden boat restoration experience:
Carefully tack clothed every surface just before applying anything. Dust kills!
Applied Cuprinol Clear around all joints while rotating wheels about 90 degrees at each application to use gravity to improve saturation into the joints
Applied Cuprinol Clear to entire surface after adding a very tiny amount of a golden oak stain to my taste
Applied 5 light coats of a high quality ‘Spar’ varnish being careful to avoid runs & doing only 2 wheels per day.
Use only a high quality very fine bristle brush for varnish. Backbrush lightly and frequently while the brush is fairly dry, but do it very quickly before moving on the next area. The biggest appearance issues will show up at transition areas, so try to not go too far too quickly.
I will only use a varnish that will allow re-coating within 3-4 hours without requiring sanding. The brand that I used back then has since gone to a water based formula that I do not trust, but there are other brands that will allow recoating the same day without sanding. Timing recoats is usually a narrow window. You do not want to have to sand between coats except to smooth any runs. If you do that, make sure you tack cloth the entire area very carefully before the next varnish coat.