Seiko stw 8 / consew 225 what to adjust?

[bigsig11010]

Same stw 8 that I have been asking about. Ordered 138 thread and 135 x 16 size 22 needle. I have also changed the motor pulley to a 2”. I have ordered servo motor from Toledo. So test drive with new thread and needle. Only 1 layer for test but the back side or bottom doesn’t look right. What do I need to adjust and how do I adjust it? I had to downsize the pics to be able to upload as per attachment requirements. 
 

any help greatly appreciated. 
 

 

[sandmanred]

I'd start by increasing the top thread tension, it should help pull the knot up tighter.

[Pintodeluxe]

Try putting something in the machine that you'd actually sew and play around a little more.  Maybe two layers of that leather.  Increase upper tension for sure, but you may have to adjust the bobbin tension as well.  

Also a #23 needle may help you sew 138 thread in leather.

Best of luck with it.  

[DonInReno]

Upper tension.

 

[bigsig11010]

Ok added upper thread tension and tried 2 layers. I did not adjust stitch length at all but the stitches are much shorter on the 2 layers? Why is that? 
 

on left is 1 layer on right is 2 layers.
 

also looks like bottom or back side getting worse not better. 

[Constabulary]

I don´t know your tension spring but maybe a heavier type beehive spring could help too. Juki parts is # B3114-232-000. You should get them from most industrial sewing machine dealers. They usually cost 2 bucks or so. Maybe worth trying.

Or try a larger needle size . Stitches on most needle feed / triple feed machines become shorter the thicker the material. That's the pendulum effect of the needle bar. Add another layer and stitches will be even shorter.

Edited March 16, 2021 by Constabulary

[DonInReno]

 It looks as if something is keeping the bobbin from releasing thread properly - that’s keeping the material from feeding (short stitches) and not allowing the knot to be pulled up correctly.  How have you adjusted the bobbin tension?    Holding the bobbin case by the thread tail tension shouldn’t be so loose that it falls to the floor, but jiggling the bobbin case should let out more thread.

 

 

[bigsig11010]

I’m embarrassed to say I don’t know how to remove the bobbin case. I took out the bobbin but couldn’t see how to remove the case and didn’t see on YouTube how to remove it. 

[nylonRigging]

47 minutes ago, bigsig11010 said:

I took out the bobbin but couldn’t see how to remove the case

edit to change .. thought it was bottom load .

OHHhhh .. must be ( Top Load ) Bobbin ?.

Your Tension is on the side ( staring up at you )  it's the 'spinning basket'  you removed the Bobbin out of . just start looking around the side that is exposed to you, and you will see the tiny screw that adjusts the little leaf spring that the Bobbin thread is routed threw . .

https://sewing.com/sewing-machine-parts/

.

Edited March 16, 2021 by nylonRigging

[DonInReno]

9 hours ago, bigsig11010 said:

I’m embarrassed to say I don’t know how to remove the bobbin case. I took out the bobbin but couldn’t see how to remove the case and didn’t see on YouTube how to remove it. 

Ooops - that’s my mistake - there is no removable bobbin case on this model.