When applying the new finish only use shellac and linseed oil. The linseed oil will come to the suface as the shellac cures. the linseed oil is compatible with the shellac and will not harm the finish. I think you are over thinking this process. After the shellac as cured for a week you wipe the machine down lightly with naptha to remove the film of oil. The machine after this wipe down will look a little cloudy. the final waxing of the machine will bring the shine back and remove all the cloudiness you may or may not have. Don't mix the shellac and linseed or alcohol in a container. Just wrap the cloth around your finger dip in shellac and place a drop or two of oil on top and start french polishing. The oil will help your rag from sticking to the finish. the oil just helps for a smoother finish besides keeping the rag from sticking. I do not want to go into a chemistry lessons LOL so please don't over think this process. No rememner you may not get some of the rough spots as smooth as you like because the japan finish as it ages will cause high and low spots that can be a little rough. You can't replace the japan finsih which is the black undercoat. these machine are old and will show age that can't be completely removed. Keep asking questions that is what I am here for. Just have fun with the process and don't to hung up on the details. Take your time this system does work well.
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