Originally Posted by
annf
Thanks so much for the ideas and theories. I think it is rust, the face plate and pressure bar had a bunch, but I'll wait for the ceramic lube, before I get much harsher, especially since the screws in the linkages aren't letting me unscrew them.
I've cleaned, got the Dremel out, figuring that might vibrate things a bit. And because of that great comparison link that Tammi posted have switched to trying liquid wrench, which seems to leave a foamy residue... Been wiping that off before reapplying.
I don't have a torch, but maybe I could try my heat gun... just concerned since the needle bar is a hollow one that it'll be more likely to break.
Thanks so much for all the posts, it's been getting past the point where I've been wondering if I was missing something obvious...
For screws like the one holding the needlebar that won't budge - I'm going to make some people cringe here, ready?
- stand the machine on its handwheel and let the liquid wrench soak right into where the screws are seated instead of having it drip down the needlebar. Marination vs rotisserie style.
If you do this though - prop and brace it really well so it can't fall over - especially if you have furry or little "hands" around.
That said, I don't know how much loosening the linkages will help. Perhaps see if you can loosen the set screw for the needlbar bushing as well though, since you might have to take it out to remove rust anyway.
I think a heat gun should be fine if used judiciously. What I remember reading - maybe in that thread I posted - is heat is good - color change (i.e. red hot) is not so good. I don't think a heat gun will do that sort of heat.
I don't think you're missing anything obvious. Some of them really are this tough to get moving again. It didn't seize in a day, sometimes you won't get it loose in a day either.