Cobra Class 4 Stitch Question

[Wager]

Hi Leatherworkers!

I've been following the forum for a while, and because of the great info on this site I just purchased a Cobra Class 4. I just picked it up today and couldn't be happier.

To get a little practice under my belt, I did my first few stitches on some scraps. Although I saw Steve do some really nice stitches, I'm unable to figure out how to solve the problem in this picture. My bottom thread doesn't seem to be pulling through far enough. The leather in the picture is 2 pieces of 2/3 oz veg tan.

Any help would be greatly appreciated!

Thanks,

Joe

[gottaknow]

Hey Joe. Either your top tension is too tight, or your bobbin tension is too loose. I usually start loosening before tightening, so loosen your top tension a little at a time until the stitch is balanced. You can also do a little of both. Tighten the bobbin tension a little and loosen the top a little. You'll figure it out in no time. Enjoy your new machine!

Regards, Eric

[pcox]

If thats the bottom you need more top tension. so thats the top forget what I said. Wizcraft & gattaknow

has you on track

Edited December 9, 2012 by pcox

[Wager]

Thanks guys, that's the top. It seems a bit tricky to tighten the bottom tension on the class 4, unless there's something to it I'm not seeing. I'll keep at it, any more tips would be greatly appreciated!

[Wizcrafts]

If the photo is taken from the top of the leather, either the top thread is wrapped incorrectly around something it shouldn't be wrapped around, including itself, or a post, or one of the 2 disk sets, or the bobbin thread has come out from under the bobbin tension spring.

If the photo represents the bottom of the leather, either the top thread has come out of the tension disks, or is not feeding through the take-up lever, or the bobbin thread is too tight, or the needle is too big, or the thread is too big for 6 ounces of leather.

[Wizcrafts]

Thanks guys, that's the top. It seems a bit tricky to tighten the bottom tension on the class 4, unless there's something to it I'm not seeing. I'll keep at it, any more tips would be greatly appreciated!

Yeah, I Grok your pain. There is a little flat blade screw inside a hole in the bobbin case, forward from the tension spring screw. The screw inside that recess locks down the tension screw. Use the small screw driver that came with the machine to loosen the set screw, then adjust the tension screw for more bobbin tension. When you are happy with the back pressure, tighten the set screw to keep the tension screw from backing out.

[Wager]

Thanks Wiz! I'll give all of these tips a shot. Much apprecaited all!

[Andrew Chee]

Just out of curiosity, what size thread do you have in there? Looks pretty heavy. A heavy thread in something as thin as two layers of 2-3 oz is a little more difficult to get the knot in the middle simply cause the knot is so big. If you're sewing something this light, try a lighter thread as well.

Andrew

[Wager]

I'm using 277. I finally got it somewhat dialed. The thicker leather worked best for sure, and I'm pretty convinced it's the size of the thread for the thickness of leathere I'm sewing.

Thanks for the help all!

[Wizcrafts]

You should move down to #138 thread if you want to sew 4 to 6 ounces. #207 would be as large as you could really.sew at that thinness. You should use a #23 needle for #138 thread, or a #24 for #207 thread, top and bottom.