Kakky Report post Posted June 28, 2019 Hey folks! I am having difficulty with getting a good bottom stitch for our leather products. I am finding that the top has a very even and good look with deep holes, but the bottom is coming out sort of rough and crappy looking. I don't think it's necessarily a tension issue, maybe the needle we are using? does anybody have a suggestion on how we can get this stitch look a bit more professional? Thanks! Quote Share this post Link to post Share on other sites
kgg Report post Posted June 28, 2019 More info please. Like what size thread (top and bottom)? type of thread (bonded nylon, bonded polyester)? size of needle being used? needle leather or fabric? Juki model Juki? type of leather? kgg Quote Share this post Link to post Share on other sites
Kakky Report post Posted July 8, 2019 Hello! Thanks for getting back to me! Thread is 138 nylon needles are NM: 160 size 23 135 X 16 DIA from Schmetz something they were calling a leather point Juki is LU-1508N and the leather is a chrome excel about 3/4 gauge hope that helps! Quote Share this post Link to post Share on other sites
kgg Report post Posted July 9, 2019 According to the Toledo Sewing Chart ( https://www.tolindsewmach.com/thread-chart.html ) you should be using a size 22 / 140 needle for V138 thread. This may affect the look of the bottom thread and have you adjusted the bobbin thread tension? Uwe posted awhile back to a good link for the Juki LU-1508N user manual if you don't have a copy (Juki LU-1508N Instruction Manual.pdf) look at page 31. A picture showing your thread path from the top thread spool too the tip of the needle would also be helpful, just in case something else can be spotted. kgg Quote Share this post Link to post Share on other sites
RockyAussie Report post Posted July 9, 2019 I am not familiar with chrome excel so I need to ask if it has a hard top surface? Softer leathers tend to be easier to work with when it comes to machine stitching. The smaller needle @kgg may help a little as you should be able to reduce the foot pressure some and get less distortion from the dog feet and hole. A smaller needle will pull out easier. I would also try a softer thread than the nylon as they should allow it to sit down and suck in a little better. Quote Share this post Link to post Share on other sites
TonyRV2 Report post Posted July 9, 2019 Chrome tanned leathers can be soft and sticky when it comes to feeding through the machine and it looks like in the lower right part of the wallet that the material shifted on you. Have you glued the pieces together prior to sewing? This should help. Also, a part of the problem is the marks left on the leather from the feed dog. Try loosening the presser foot tension a little. You need enough pressure to reliably feed this kind of material but not so much that it leaves a bad impression on the top or bottom. A smooth rather then toothed presser foot or even a roller presser foot would be a good idea here. I magnified the photo and it also looked like the knots were showing in a few spots. Since this is the bottom side you can fix that by slightly increasing the upper thread tension. ...Tony Quote Share this post Link to post Share on other sites
Northmount Report post Posted July 9, 2019 You can tap the bottom stitch with a smooth hammer to help improve the looks. Tom Quote Share this post Link to post Share on other sites
