Help needed with tension issues on 441 clone.

[Watts]

On 5/13/2021 at 3:30 PM, garypl said:

I've had issues with needle thread fraying on the upstroke when I had top tension too tight.  I generally set bobbin tension so I can pull the thread out fairly easily by hand, then adjust the top tension for the leather you are sewing so the knots are pulled up into the leather.  Some really hard leathers are just plain difficult to sew.  I had one holster that had a spot that was so hard the needle bent.  I ended up drilling a hole in that spot to allow needle to cleanly penetrate the piece.  The rest of the project was no problem - go figure!

I believe my bobbin tension was too tight, and therefore making it impossible for top tension to ever equalize. I also tightened my presser foot pressure back down and this seems to have helped as well. Thanks

[Watts]

On 5/13/2021 at 1:22 PM, Silverd said:

if the material you are sewing is not evenly flat on the bottom it can prevent the knot from getting pulled up into the material.  

If you are not holding the material flat against the needle plate it can cause this issue.

If there is a gap between top material and bottom material it can cause this issue.

If the material you are sewing is very stiff (Temper is high), it can prevent the knot from pulling up into the needle hole...Hence the suggestion to use the next size needle up.

Casing the leather slightly on the bottom side only can help if high temper is the root cause.  I use a misting sprayer from Tandy for this purpose.

Pressor foot pressure will effect if the knot is pulled into the needle hole as stated above.  Material should not lift off of the needle plate while sewing.

Installing the bobbin the wrong way can cause this issue.   Consult owners manual

Using a size down thread on the bottom will help

Calibrate the bobbin tension by using a single coke can (full) as a known weight source. Bobbin tension should be set such that when the can is tied on it barely pulls thread out of the bobbin.    Start there then change to suit your particular project needs

The thread must wrap 2X around the last top thread tensioner disk although the first disk has the most influence.  

 

Hope this helps!

 

Silverd

Good tip for bobbin tension, haven’t heard much on that previously  other than leave it where the dealer put it and hold your mouth right. 

 

I sewed up a heavy belt this evening and it did good. Thanks for the run down. 

[Silverd]

Certainly

 

Silverd