Techsew 5100 back stitch problems

[catskin]

I find that it depends on where the needle is when you change from forward to reverse. Make sure the hook has caught the thread on the last stitch before changing to reverse. If you change directions at the wrong time it will miss catching the thread for the first reverse stitch.  Or it does on my CB 4500.

[ZacharyR]

I appreciate all your help and advice. I played with the check spring some. I’ve gotten it to be able to back stitch some of the time but not reliably. I’m starting to think that small of thread is just not going to work very well. 

[Wizcrafts]

39 minutes ago, ZacharyR said:

I appreciate all your help and advice. I played with the check spring some. I’ve gotten it to be able to back stitch some of the time but not reliably. I’m starting to think that small of thread is just not going to work very well. 

For small size thread the check spring travel is also important. If the spring holds onto the thread too long the loop might dissolve before pickoff time. The bottom stopper can be raised to stop the spring earlier. This adds more slack that might help the loop.

Another thing is thread twist. If the thread is twisty it might turn away from the hook. You can offset clockwise twist by wrapping the top thread counterclockwise through two holes in the top thread post. I use the top and bottom holes to do this.

[Gump]

I had this problem and it was the hook timing. Roll the machine forward and note where the hook and needle meet, then put machine in reverse and see if the hook and needle meet in the same position as forward. For some reason mine was way late in reverse. When hook timing matched in forward and reverse I had no more problem with skipped stitches.

[Wizcrafts]

Hook timing on machines with reverse should be done with the stitch length position set to zero movement.

[shoepatcher]

You may have to time it in reverse.  When reverse lever is engaged, it moves the feed dog. 

glenn