Cobra Class 20 Tension

[Trace]

I have a new Cobra class 20 and have been having a problem with the bottom tension looking as nice as the top. Please see attached pictures of my stitch. The needle, thread and machine are less than a month old. Using 207 bonded nylon thread top and bottom with a 135X16 size 23 needle. I have tried multiple adjustments, rethreads and nothing seems to make it better. The leather thickness doesn't seem to be playing a part either. I also tried 207 top and 138 on the bottom and it looked worse. I just assumed for that time it was needle punching a bigger hole than needed for the 138.

[stelmackr]

I am learning about sewing machines, so take this with a grain of salt.

When I sew on a Consew 206-RB (or a Pfaff-1245 (both are FERDCO clones), I use a #23 needle with 207 thread top and 138 bottom, but it is a LR needle. It cuts a 45-degree slot and it closes the stitch up as it sews. I have used a blunt or pointed needle on leather and it looked much like your stitch both front and back. Looks like the tension is putting the knot in the middle, but the total tension top and bottom might be too tight along with the foot tension.

There I've said it. Now wait for the experts to give you the real answer.

Bob Stelmack

Edited November 28, 2015 by stelmackr

[Trace]

Hi Bob

Thanks for the reply. I will check into the foot tension along with the others. It seemed to sew really nice at the store and I am trying to duplicate that. I will try to call Cobra Steve sometime Monday and see what he thinks as well. I will check into the LR needle and see what that's all about. Sounds like a good thing.