oldsewnsew

not worth doing on bobbins, but their is a process called electro-polishing, which would remove outer layer of molecules leaving shiny behind. Their are probably other eletrode charge methods that would reverse the process. Any chemists/ metalurgists here?

Jingle

I think a lot of the problems arose from the length of the soaking. A few minutes may have been better.

SteveH

I have never tried "electro-polishing" but my electro-plater does "electro-cleaning" which is basically reverse electro-plating (un-plates it) very electro....


I have a spare bobbin case. I'll start it soaking in vinegar tonight, in a week or two we can try the electro-clean process

linda faye

Heads up! Go to novamontgomery.com Nova has lots of advice about cleaning and maintaining your sewing machine.

oldsewnsew

did you rinse them in water after the vinegar? to stop flash rusting from ocuring. Rinse them, use a toothbrush rinse more and dry them. you might consider another quik acidic cleaning and neutrslize with baking soda. Play around snd you might discover the answer,

vmaniqui

dont soak it in vinegar. Just send it my way

minibarn

Just jumping in here w/a question...how do you clean the tension spring?

Jp

path49

Just remove the screws that hold it on & clean/polish the underside....you'll have to remove the tension screw AND the screw that holds it on the case. They're little...so be careful with them. Also clean/polish the part of the case that's underneath it. And put it back together. That's the most important area of the bobbin case to clean...the thread needs a nice, smooth pathway.

vmaniqui

I tried everything. I even used my dremel and same thing. Just got a little bit of shine. Put brasso and buffed it with my dremel and nothing. Even used metal brush on dremel and nothing. I guess I just need to get another one. Anyone has spare bobbin case for 15-91, 15-90 or 15-88?

SteveH

1. We can fix this in my shop
2. I may have a spare.