Sewing machine mechanics!!?

Question

I have an industrial sewing machine and the foot has jammed neither up nor down, so it is impossible to sew!
It had been stood for a long time and I have dowsed it in WD40, the oil in the machine is fine.
It seems to be the shaft (with the foot on the bottom) which has siezed, any ideas?

the foot is operated by either a lever (you push with your leg) or a lever at the rear of the machine head. It is solid whichever way. I took the end panel off the machine and all the workings are sound up to the shaft with the foot on it, plenty of lube!
If I loosen the 'clamp' which should lift the foot up the shaft moves, just the foot shaft that is stuck.

Answer 1

Oh boy.... its been awhile, heheh...

Ive seen these things run 3 ways... an electrical pedal, pedal connected to a chain, or cable, and pedal connected to shaft.

If youve got the model with a shaft running up from the pedal.... you should be able to follow the shaft up the back of the machine, it should connect to a cross lever, which eventually connects ... and so forth...
Youre going to have to follow the linkage all the way, and give a light dose of oil (just a drop or two) at each point. Give the shaft a jiggle, and the following linkages as you trace it, till you run into where it is locked up tight.

By the way... most of these things are adjustable... if yours has set for a long time, its possible the shaft has dropped, and may need to be re-adjusted. Normal operation is that stepping on the pedal brings the shaft down....if the shaft adjustment linkage has dropped, you can't push it down, it is already down. There should be at least one, possibly two set bolts where the shaft is attached to another rod coming down from the back of the machine. Sometimes they overlap by as much as a foot. Release those securing bolts and it should slide up and down the shaft coming down out of the back of the machine.

Have Fun

Answer 2

First of all, never use anything other than sewing machine oil in a sewing machine. Not WD-30, 3in1 or anything other than real sewing machine oil. If the machine is still under warranty, and you bought it from a dealer; then go back to where you purchased the machine. If you bought it used or it's quite old, then you might need a trip to a professional. There could be something in the mechanism, dirt, grime, lint, broken needles, broken gears or grease that doesn't allow the shaft to move freely. It could also be oxidized in place, that is rust. It doesn't need to be thick rust normally associated with cars and such, but it could be rusted tight. It could be a stripped or broken gear. Whatever it is, it sounds like you need to take the outer case off the machine and carefully examine the inner workings of the machine and see if there's anything where it shouldn't be. My technician loves to tell the story of finding a dead mouse jammed in a gear. If a machine has been in storage it's best to have a profession sewing machine technician get it ready for use, so the best option might be taking it to a repair pro.

Answer 3

It may be some parts stuck. You may need open it and check. Sewing machine is still much simpler than a car. Please check the link below. It may give you some help.