Trouble with 52w22

[bootswithjay]

I am currently struggling with the 52w22 post stitch twin needle and have a couple of questions. 

1) My top stitch is not locking with may bottom thread, resulting in the lack of a finished stitch. It will occasionally catch, but not always. Currently I am using a fairly cheap nylon thread. Could the thread be causing the issue? Is it a problem with tensioning? Or timing?

2) I need a second needle set screw. the gentleman who had it before me only used it as a single needle machine. Does anyone knew if other set screws from industrial machines could work?

 

Thanks for your help.

[Constabulary]

Posting pictures will help to figure your problem.

Needle clamp screw should be parts number 201030 and should be available from a sewing machine dealers.  But better check the parts list of your machine.

Check the needle hook timing when the hook is not catching the thread. Most likely needle bar is a tiny bit too high.

Edited June 28, 2021 by Constabulary