Techsew 5100 back stitch problems

[ZacharyR]

I’m trying to sew 2-3 layers of 2 oz leather which I know is pushing my machines limits. I’m using #92 thread and #20 needles. I’ve read the stickies and tried to follow them but my problem is that it will sew it won’t backstitch. It sews fine forward but when I try to back stitch at the end it misses the bottom thread almost every time. I’ve tried adjusting tension and everything I can think of but it still does it. What am I missing? Thanks 

[MtlBiker]

21 minutes ago, ZacharyR said:

I’m trying to sew 2-3 layers of 2 oz leather which I know is pushing my machines limits. I’m using #92 thread and #20 needles. I’ve read the stickies and tried to follow them but my problem is that it will sew it won’t backstitch. It sews fine forward but when I try to back stitch at the end it misses the bottom thread almost every time. I’ve tried adjusting tension and everything I can think of but it still does it. What am I missing? Thanks 

2-3 layers of 2 oz leather shouldn't be pushing that machine at all!  Even my 2750 has no problem with that thickness of leather.  Is your machine working the way it should with other materials?  Is it only with the leather that you have a problem?  Are you using leather needles?

[ZacharyR]

I’m no expert by any means but if I switch to #138 thread and a #23 needle it sews the same leather fine. I got the needles from techsew. They’re a round point needle instead of a chisel point. 

[JayEhl]

I have the same problem.  I heard from a friend who suggests leaving enough tail on both ends to allow for hand back stitching until I get it figured out.  Granted I'm still very much a novice with this machine so I know its something I've screwed up. I just need to spend more time on it is what I was also told.   Was hoping for a better answer but unless it's mechanical, e.g. the machine isn't working to stitch back, then it's definitely something to do with thread type, thread size, needle size, or tension as far as I can tell. 

Was also told that once it's set, don't mess with it!!  

[ZacharyR]

I hadn’t thought about trying that. Mine sews everything else just fine with bigger thread and needles 

[MtlBiker]

11 minutes ago, ZacharyR said:

I’m no expert by any means but if I switch to #138 thread and a #23 needle it sews the same leather fine. I got the needles from techsew. They’re a round point needle instead of a chisel point. 

Round point needles are not leather needles. 

Okay, I suspect your stitches (with the needle and thread you're using) aren't correct.  Can you post a photo of the forward stitches, both top side and under side?  Since you say there is no problem when you're using #138 with a 23 needle, I suspect the tension adjustment is off and showing us the stitches would help us help you.

(Do you know how to adjust the tension on the bobbin carrier?  Certainly changing from 138 to 69 would require readjusting that.)

 

[ZacharyR]

I can try to get some pictures later. I know how to adjust the tension on the bobbin. I usually just adjust it so the knot is in the center and it seems to be there so I haven’t messed with that tension yet. Maybe I should try it with my bigger needles and see if it changes anything. 

[ZacharyR]

Here are the needles I’m using with the #92 thread. It says they’re for leather but I don’t know that much about it. 

[MtlBiker]

@ZacharyR - While you can use those universal needles on leather, they are not ideal.  You should be using these:

I still wonder if your thread tensions are correct.  There's no doubt in my mind that when you change from 138 thread to #69, you must readjust the bobbin tension as well as the top thread tension.  I also think what you're using is at the lowest end of what the machine is capable of using and that ideally that machine uses thicker thread and bigger needles.

[ZacharyR]

I have some of those needles as well I just can’t find them as small. I know I’m going about as small as this machine can do and that’s not helping. I’ll try it some more this evening and adjust the tension on the bobbin and try a different needle and see if that helps. I appreciate your help and information.