Thread gets caught under hook occasionally

[Uwe]

I've had occasional trouble on my Consew 225 with the thread getting caught under the hook. Today I figured how it happens and I can make it happen. What I haven't figured out yet is how to fix it. The machine sews perfectly on a normal run and timing is generally spot-on. But if I happen to stop the machine at the exact wrong moment and touch the hand wheel, it may cause the thread to get caught under the hook.

Patient:"Doctor, if I do this it hurts"

Doctor: "Don't do that"

The "wrong" moment is exactly when the needle exits the material. This may happen occasionally and if turn the handwheel back just a tiny bit to bury the needle again for a turn, trouble ensues.

I'm wondering if the design of the new hook is contributing to the problem. The problem happened quite often with the old, original hook, which is why I installed a new hook. Alas, the new hook doesn't prevent the problem entirely.

I had messaged with Eric about his problem (before I figured out how to repeat it). The issue may be of general interest, so I'm throwing it up here to crowd source a potential solution and share the fix.

Here's the video of the problem:

 

 

Edited June 4, 2016 by Uwe

[mikesc]

Would it help if the machine had something like the "thread guide with a felt pad" ( which is supposed to be drip fed with oil originally ) which is on my singer 211U166, while the thread can sometimes be a little slack above it, ( where the thread comes down from the "take up arm" ) below the felt pad and its holder, where the thread passes over the slight resistance of the felt pad ( and on down to the needle ) it is never so quite so slack ..Not saying necessarily to fit a felt pad and bar to your consew, but maybe introducing just a slight resistance along the path of the thread between the take up arm and the needle ?

Removing some of the slackness below the take up arm is what I'm thinking of..even a tiny amount of resistance might work, without affecting "normal" good stitch formation.?
Maybe just passing the thread across a felt pad stuck somewhere on that pathway with velcro , or double sided tape?, or just passing the thread across the "fluffy" part of some stitch on velcro somewhere where the thread passes over the machine body in that pathway just before it goes down to the thread guide on the needle bar above the needle..?

Edited June 5, 2016 by mikesc

[Wizcrafts]

Uwe;

Try re-positioning the slot in the check spring regulator bracket. If that doesn't matter, try lengthening the travel of the spring.

[Darren Brosowski]

A common issue with horizontal shuttles.

Vertical shuttles are less fussy

[Constabulary]

My 2 cents from just watching the Video:

I think you cannot  fix this even with more travel on the regulator spring. You just have to make the turn when the needle is in deeper position. The thread is "caught" in the needle hole (in the material) so I don`t think there is much you can do.

[Coeta]

I would also guess there is too much friction/stiffness on the thread at the needle hole as Constabulary suggested...

I had similar experience when I used that sticky double sided tape when preparing to sew the material together.. when I sewed I had endless trouble with the thread not been pulled up back quick enough by the regulator spring no matter how I adjusted it...that double sided tape was just to sticky for the thread to be pulled back  quick enough....after I removed that tape I had no issues...

With your experience you should be able to figure it out....

[gottaknow]

I still think your shaft timing is off one notch. Your top shaft is ahead your bottom shaft.  Either that or you little to no tension on your check spring. As Wiz suggested, your travel on your check spring is too short. If your shaft timing is good, and your check spring has enough tension and travel, your thread should not have any slack before the needle penetrates the material you're sewing. I don't think it's a position thing with where your hook stops. It happens too often from what you told me than a 1 in 360 chance of stopping and then touching the hand wheel slightly backwards. Unless someone has the bad habit of turning the hand wheel backwards all the time I think it's a machine setting. My 211's with clutch motors rarely do this and we use them 40 hours a week. 

Regards, Eric 

[brmax]

Interestingly I watched "ya got me" many rewinds also.

I considered in this order initially: Weird new hook style and its lower notch,  Then I looked and wondered at timing a bit, at this time remembered some mention of needle turned a bit for different issues talked about in some post.

Then considered the needle pushing the thread down? as maybe scarf hole a bit small, it was late.

I had also looked at the take up spring and kept saying to myself I think its design "way before me" was to be level across and it does look pretty close to that so I'm up in the air for a couple more video/look n see.

Took a look around here and considered the spring/hold down after take-up lever on my juki, like an oil pad on some others, but looked at the singer and no such design so religated that for further study.

Today I will commit to a spring further look and if adjustable try it, I do recall some mention of them broke yet looking perfect, fwiw.

It seems no matter my other mentions the spring should have some tension and with groove in the needle letting it return somewhat.

I'm here with toothpick at the cutting table in curious wait

Good luck on your mission Uwe

[mikesc]

 

Quote

like an oil pad on some others, but looked at the singer and no such design

Singer 211U166 does have an "oil pad" in the downward thread path, between the "take up arm" and the thread guide on the case just above the needle bar ( hence I mentioned it above ), normally it is for oiling the thread, but it does add a tiny little bit of extra friction on the down path, and thus there is less "slack" below it than above it, that said, I bow to the far greater experience of Eric and Wiz, probably a tiny tweak on the timing and or the spring is "the fix"..

[brmax]

Totally understand Mike, I was turning around looking at mine a 212, it I'm sure has the option in parts books but mine just a plain ole guide.

We are in agreement inquiring minds here as members are always interested in the great experience others share.

I had to step over and took a better look at a 1508 and sorry! spring has no issue here at this point as it the hook is way past this take up spring in its cycle, I'm seeing its finished its job at needle material entry so slack is now in design ?(I think and ask)

Now am I in school?

I am running solarfix in that machine so the same action is keeping thread in memory for a 1/2" or the hook gap anyway, but this could very well be the same with some other poly or nylon so I am considering twist in thread also at the moment.

I would say the 1341 has many hook aspects of others and I don't know enough to say which but will go on to say the hook has a plate on the bottom and whatever other reasons it does infact help curtail this "post" issue. The hook here has a slightly different thread resting area but with poly it comes out of that machined designed groove and as mentioned kept in check with the plate and so as hook follows through forced back in before the final release.

So at this point of my homework interest, My stuff is wacked and or I need another consideration with threads also.

Coffee time, and thanks for the run through no doubt always of interest

Floyd