To finish up I would give the whole a light french polish, let it cure for a week or so then use car wax to shine it up and protect more. I use a good mcquires carnuba car wax. The machine is looking good. I really don't think the naptha reacted with the shellac, Naptha just removed all the dirt and oil so you could see problems. I am glad everything is going well on the machine. Good job. Let me know if you nedd anymore help.
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