Just started making plugs,and found out the hard way that the wood had to be sealed with more than primer. I browsed around the site for sealer info. I saw a mixtuer of 70/30 spar urathane and mineral spirits. Witch is 70 and witch is 30? Is this a safe mixture?

Safety is all relative... read all labels/warnings/etc...

70% spar, 30% thinner of your choice (if you got that route).

Welcome.

when you guys seal them do you apply it with rags or just dunk them in

Just dunk them and try to get it so that it goes into all drilled holes. hlf hr then wipe off. Let dry then do it again the same for best results. This keeps the wood from taking on to much sealer and adding weight to the plug.Ron