Please Help... 441 Skipping Stitches In Reverse / Hook Hitting The Needle

[oclack]

I’m pulling may hair out… Right in the middle of a production run my SewPro Mini-441 machine has flaked out on me.

The machine seized suddenly in the middle of a stitch line. I removed the bobbin case and cleared the jammed thread and also took a moment to change out out the lower feed dog - I went from a toothed to a smooth one. Now it seems the timing is off.

I’ve made adjustments by repositioning the bobbin case (as shown in the Al Bane video). I also installed a new need just in case it was bent - that hasn’t helped. The machine is now stitching forward cleanly, but skips stitches going in reverse.

The machine has always made clicking noises, but I never paid much attention it.

I now believe (I’m nearly certain) the hook is hitting the needle with each revolution - just worse than before. The needle doesn’t seem to be coming in contact with the deflector at all, but does rub the hook. At first It wouldn’t stitch forward at all, so I adjusted the bobbin case and now forward is okay-ish - but the needle still comes in contact with the hook. I’m certain that shouldn’t happen - right? On reverse it may catch one or two stitches, then skips all the rest.

Any ideas or help you can offer would be greatly appreciated.

[Wizcrafts]

First off, remove the throat plate and hand wheel until the needle reaches BDC. Slowly continue hand-wheeling until the needle ascends about 3/16 inch above BDC. The hook point should be near the center of the scarf on the right side of the needle, and definitely well above the eye. If the hook is above or below the cutaway scarf, either the needle bar or the shuttle has moved from the original timed setting. With thread jams, it is often the hook that gets retarded, causing the hook to intersect the plane of the needle at the wrong time. If you see the needle has moved up about 3/16" and the hook has not yet intersected it inside the scarf, you will either have to lower the needle or advance the hook.

Lowering the needle bar is the easiest fix people apply when the timing changes. But, if the problem was caused by the hook being retarded, the lowering of the needle reduces the maximum thickness that can be sewn by the amount it has been moved below factory specs.

Consult your owner's manual to learn how to adjust the position and timing of the hook.

[oclack]

Wiz,

Should the needle ever come in contact with the point of the hook? On the down strok the need briefly slides down the left side of the hook. On the susequent up stroke the hook point touched the needles scarf before piping to the right.

[Cobra Steve]

Odin, besides what Wiz has advised you on(which is all true), the hook should not hit the needle. You may have to check if the collar that is on the hook driving shaft has slipped. A good indication is if there is play in that shaft. With the shuttle hook out of the machine, see if you can move the shaft left to right. If you can, then it is probably one of the collars on that shaft. There also could be play in the needle bar rock frame, but this rarely happens. Thanks, Steve Hi Wiz, hope all is well.

Edited April 11, 2014 by Cobra Steve

[oclack]

Thanks Steve and Wiz. Steve we spoke briefly yesterday... I'll be ordering a DVD and new pressor feet from you soon.

I was hoping to get this machine back in working condition quickly, but I'm a bit dubious on that now. Here's a quick video of the action. I think it may show the issues more clearly.

A close up of the need hitting the hook:

http://youtu.be/54smDtS-ClY?t=17s

A view from the front... You can see the needle jump/pop as the hook passes it:

http://youtu.be/uSWtSpEox0k?t=22s

A view of the complete action:

http://youtu.be/vQsVdRFoIJQ

I'll check for play in the along the hook drive shaft as Steve mentioned, when I get back to the workshop.

[oclack]

Okay. I've checked for play in the drive shaft - there is none.

At the same time I did take notice of what I'd call as gasket in the assembly. I don't know the technical terms for the parts, so I've attached a picture below. The part doesn't seem to be original - in fact is almost looks hand cut. Can any tell me if this is a standard part on 441 machines?

I removed it and tested on some scrap. The shuttle hook doesn't seem to be touching (i.e. scrapping) again the needle on the up stroke, but it does have a little contact on the down stroke - but far less than before.

[Wizcrafts]

Wiz,

Should the needle ever come in contact with the point of the hook? On the down strok the need briefly slides down the left side of the hook. On the susequent up stroke the hook point touched the needles scarf before piping to the right.

No. The hook should pass inside the scarf area above the eye without actually making contact. Some adjusters use a standard business card to set the clearance between the hook and needle.Most 441 machines are setup by the dealers who sell them. Most set them up with a #25 needle and #277 thread. It is possible that the dealer who setup your machine had it adjusted for a #22 needle. This would allow the hook to miss the needle with the spacer that you found. Then they forgot about it and gave you a pack of #25 needles and they are making contact with the misadjusted hook.

Usually, the hook on a 441 or 205 can be set to just miss touching the largest anticipated needle and still pick up the loop 3 needle numbers smaller. Thus, a well timed machine setup with a #25 needle should also sew well with a #22 needle. After that all bets are off. But, it doesn't work the other way. You should get the hook set for the largest needle you will be using, with the stitch lever in the zero position. This balances the hook between forward and reverse motion. Make sure the hook just misses making contact with an empty needle, as it passes inside the scarf area.

[oclack]

Well fellas! I think I've got it. With help from Wiz and Steve, the problem seems to be resolved. The machine is stitching forward and reverse without skipping the the obnoxious clicking (and probably damaging) caused by the needle rubbing the hook is gone - and I pray is stays that way!

Using Wiz's recommendations, I removed the weird spacer and set the stitch length to zero before adjusting the shuttle position to set the hook in the middle of the needle scarf. I also set the needle back to the top of the bar. Finally I have the hook assembly a good oiling and that removed the last bit of rubbing (I don't understand why, but it worked).

I'm relieved and ready to get back to finishing this run of satchels. Learned a lot, but hope not to have to apply it again.

Now if I can just figure out how to keep the needle plate and upper presser feet from marking the leather - probably a pressure issue.

Thanks all for the help!