Fraying thread

[MoMatt]

Hi, looking to understand why the top thread starts to fray. I am using bonded cowboy brand 346 nylon sewing through two 8/9 ounce Herman oak veg tan glued together with barge cement for a belt.  Tensions seem good but every so often the thread begins to fray and will break in half. Machine is the new cowboy outlaw. Will seem to sew fine for a while then all the sudden fray.  Needle is size 26. This is the fourth belt the first three sewed ok with what came on the bobbin (white 346). I used Tandy black 346 on the top.  This belt I am using white 346 top and bottom and keep having to add back stitches when it grays to start over and  It seems really bad when I back Stic, hard to get going right again,  but is now doing it without the back Stich to lock the loose end. I’m wanting not just to fix it but understand why. Pictures show good Stich, the back side, and frayed thread. Thanks 

Edited February 14, 2020 by MoMatt
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[rburson]

Check to make sure the needle is not twisted slightly if you have replaced it lately. Also double check the thread path and verify it is correct after thread change. Both of those things have caused me thread breakage and much aggravation in the past.

[MoMatt]

Thanks, I backed off the top tension a little and it seems to have slowed that down considerably. Stiched the rest of the belt nice and smoothly.  

[Wizcrafts]

You can also back off the bobbin tension to keep the knots centered. Only use the least tension that lays the thread tightly against the leather.

[MoMatt]

Wiz, Thanks I am going to try that.  Thinking about it a little,  I asked Bob to send it set up for 346 thread, but didn't tell him what I was sewing.  He had it stiching good with about a 1/2 inch of leather.  The bobbin tension is very tight, probably as tight as the top.  I bet sewing just 15 ounces or so I need to back off.    This is really fun considering what my patcher with its size 92 thread can do. 

[Pintodeluxe]

I've encountered thread fraying when I missed one of the guides close to the needle.  I've also had the thread pop out of the needle bar thread guide before I noticed it.  That lets the upper thread fray in a hurry.    

Another strange source of fraying top thread was bad needles.  That one was super frustrating, because I changed the needle and still had the same problem.  I had a whole pack of bad needles with sharp edges.  I tossed that pack and never bought the knock off brand again.  Went back to name brand needles and instantly solved the problem.    

[Constabulary]

Pictures are quite small, dark and tilt... If I see it right the thread is fraying close to of what I think is a needle guide or to the needle eye. So I would check the needle guide hole (or inner foot??) for sharp edges, I´d also replace the needle and / or go up 1 size with the needle. Maybe you even have to enlarge the hole in the needle guide slightly. Really can't tell much from the picture - tried to enlarge and brighten it but... well...

BTW - looks like the Outlaw is using Singer 111 type presser feet - is that correct?

 

Edited February 15, 2020 by Constabulary

[MoMatt]

Not sure what presser feet it has but you are right. The needle guide is where it happens.  If I go slow I can see when the thread instead of sliding through the eye of the needle bar bites in the thread. I loosened the bobbin tension and redid the top tension lighter to center the knots and it’s just as bad as before. Perhaps the needle guide needs honed as you say. I am using 26 needle and 346 bonded nylon thread. Just ruined another belt.

Edited February 16, 2020 by MoMatt

[Bert51]

I have some abrasive string I use on my guide if I think there even looks like a bump or a burr on it.

It's saved a few old guides that I would normally throw away, if replacements where still available.

Bert.

[dikman]

Try see-sawing a length of thread through the guide and see if you can feel anything catching.