LeatherWerks Report post Posted April 4, 2014 I have a Juki 1541S. I'm trying to sew two layers of common vinyl using #69 thread at 5 stitches per inch. I'm using a Groz-Beckert 135X17 needle. The bottom stitch looks perfect but the top stitch doesn't appear to be pulling up as tight as I would like. I have a variety of different needles I could use but am wondering if that's the problem. I'm attaching two photos showing the top and bottom stitches. Any help would be appreciated. Thanks, Steve Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted April 4, 2014 You need to tighten the top and bottom tensions a bit and maybe increase the throw of the check spring. Quote Share this post Link to post Share on other sites
gottaknow Report post Posted April 4, 2014 (edited) If your pics are labeled correctly, either your top tension is too tight, or you bottom tension too loose. I would make sure your bobbin has some tension on it and is in the tension spring, and that your top thread isn't just too tight or wrapped around something extra. Regards, Eric Edited April 4, 2014 by gottaknow Quote Share this post Link to post Share on other sites
LeatherWerks Report post Posted April 4, 2014 Wiz, I thought when I posted this, you might be the one who responded given that you've helped me through some sewing machine problems in the past. I understand the concept of tightening the top tension because I tried this and it seemed to help a bit. The 'throw of the check spring' is a new concept to me, and I really don't know what that means, except that the company who services this machine told me to never tighten or loosen this spring, somewhat like the conversation in the 'Garden of Eden' about the apple. Anyway, I'll work with the top tension and see where that get's me. Thanks for your response. Steve Quote Share this post Link to post Share on other sites
LeatherWerks Report post Posted April 4, 2014 Eric, I know you have some of these machines and you too have helped me through some problems in the past. The bottom stitch seems to be perfect in my opinion, I wish the top stitch looked like he bottom stitch. Would it be in my interest to try #138 thread before I made any adjustments and see what happens? Last week I was sewing some thin veg tanned leather using #69 two layers and the machine was sewing perfect. Steve Quote Share this post Link to post Share on other sites
gottaknow Report post Posted April 4, 2014 Steve, your top tension is pulling up your bobbin thread. Loosen it a bit or tighten your bobbin. The function of the check spring is to keep a slight bit of tension on your needle thread as the needle descends. This prevent the needle from sewing through your top thread. The first symptom of too little check spring action is finding your needle thread wrapped around your needle, or actually breaking the needle thread. The check spring is not for setting the stitch. That's what your take up lever and tension is for. Regards, Eric Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted April 5, 2014 I think I interpreted the two photos in reverse order when I commented. If the knots are indeed visible on the top, increase the bobbin tension. Quote Share this post Link to post Share on other sites
LeatherWerks Report post Posted April 5, 2014 Wiz and Eric, thanks for the suggestions. I'll give them a try and report the results. Steve Quote Share this post Link to post Share on other sites
LeatherWerks Report post Posted April 11, 2014 Eric and Wiz, I've been out of town for a few days but wanted to let you both know, I did tighten the bobbin tension a bit and adjusted the top tension slightly and now have a perfect stitch. Thanks for your help. Steve Quote Share this post Link to post Share on other sites