Andrew Chee Report post Posted August 5, 2013 Hello all. I have another tension problem question. I have a Pfaff 335. I have it set up with 138 thread top and bottom and a size 22 needle. I was trying to get it to sew through a single lay of 6oz W&C harness leather. It was giving me a lot of thread loops on the bottom. I had to crank the top tension all the way up and the bobbin tension all the way down just to have it make a good stitch. I switched over to stitching three layers of the same leather (skived down to 3oz each for a total of 9ozs with contact cement between the layers. Using the same setup and tension, I got thread loops all over the bottom. I tried switching to a 23 needle instead and it was a little better but I still had a lot of inconsistent tension. I've attached some images of the bottom stitches after switching to the size 23 needle. Any suggestions on what might be wrong? My top tension is pretty much cranked all the way up so I'm not sure what else to adjust now. Thanks. Andrew Quote Share this post Link to post Share on other sites
dirtclod Report post Posted August 5, 2013 I would back the tension off to nothing and start over. Then adjust a little at a time. Quote Share this post Link to post Share on other sites
Trox Report post Posted August 7, 2013 (edited) Which 335 H subclass is it? old gray or a new G type of machine. If its the old machine size might be to heavy. These small arm machines was not made for heavy thread. Edited August 7, 2013 by Trox Quote Share this post Link to post Share on other sites
Andrew Chee Report post Posted August 7, 2013 It's the new modern housing with the synchronized binder. I took a look at the timing and lowered the needle bar a bit. Then I redid the tension and things seem to be ok now. Not sure what needle bar height might have to do with tension... Maybe Wiz might know? Andrew Quote Share this post Link to post Share on other sites
Trox Report post Posted August 7, 2013 It's the new modern housing with the synchronized binder. I took a look at the timing and lowered the needle bar a bit. Then I redid the tension and things seem to be ok now. Not sure what needle bar height might have to do with tension... Maybe Wiz might know? Andrew Well, its a timing issue of the feed and the timing of the thread takeup spring. It will also affect the size of the thread loop underneath the needle plate, the needle can also cut the thread if the timing is off. Therefore, its possible you corrected the problem this way. The adjustment manual is in the download section of Pfaff`s web site if not already have it. On vertical hook machines you have the bobbin case opener who will be wrong with an timing fault too, it will affect the bobbin tension (its not a case on your machine). You better control all settings when you at it. If you do not find it I have it on pdf (it two versions depended of the machines age; one is.01.12, the other .06.09) Tor Quote Share this post Link to post Share on other sites
