Hi Nanna-up-north, I just found this machine and I guess it was my lucky day. Now for the crack in the wood. Is the crack all the way thru the wood or is it just in the surface. If it is all the way thru you need to spread it apart enough to get some wood glue in there and then clamp it closed. Filling it without this repair will only cause it to crack the filler over time and it will not do anything to stablize the problem. If you lubed according to the manual you will be okay. I use evaporust to clean the rust off the bobbins about a 30min soak is all that is needed then polish. Yes you can use metal polish if there is not much rust. Ask all the questions you want if I can't help I know members like Miriam and Cathy can help. You will like the 15-91. the potted motor as lots of power.
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