Cobra class 18

[WhiteBuff]

Can't get my machine to pull down the stitches on the bottom side of the work piece, they are staying on the top of the leather, I have tried everything , please advise!!!!

[HBAR]

If you told us what all you have tried it would help with a diagnosis. We also dont know your skill or knowledge level, so this may sound like we are talking down to you.

I have a class 18.

You understand that the top and bottom tension is adjustable correct?      If the stitches are not going down then maybe you need to reduce the tension on top.  So turn the knob counter clockwise.  If that doesnt help. You can also increase the tension in your bobbin case/carrier what ever you want to call it.

If you have tried that then let us know.  Let us know what all you have tried, what needle and what thread too.

[Wizcrafts]

I would speculate that if the top and bottom spring tensions are within normal operating parameters, that the top thread is jammed or binding somewhere along the path from the spool to the needle.

[brmax]

It seems to me even with "leather point needles" the bottom side just doesn't look as nice like the top.

I guess some of the needles pressure pushes that bottom side out and thread or its tension just doesn't pull it up, so leaves bumps of a sort. Totally understand! and on the other hand its funny how some leather will do better than others and squeeze up like a sponge and so shows on top really deep. I recall sayings, like i really didn't need a groove cut on top with this stuff. 

So possibly another method to flatten the thread on this part and keep posted on the tips you find work better, thanks.

good day

Floyd

[Wizcrafts]

In my first reply I mistakenly thought that the OP was saying that the thread knots were sitting on the top grain of the sewn piece. Upon re-examining his photo it seems that they are actually on the bottom, or flesh side. His terminology threw me off.

Knots on the flesh side are caused by any of the following:

• Bobbin thread too tight or binding inside bobbin case
• Top tension too loose or not fully seated inside tension disks
• Needle too small for the thread and leather combination

[WhiteBuff]

Ok thanks I'll try these ideas, is there a chart or some kind of guide for needle and thread compatibility ?

thanks Clint

[Uwe]

4 hours ago, WhiteBuff said:

needle and thread compatibility

Googling that exact term will bring up a bunch of reference charts, including one by our LW members TechSew Ron: http://www.techsew.com/blog/needle-thread-chart/

[Techsew Ron]

1 hour ago, Uwe said:

Googling that exact term will bring up a bunch of reference charts, including one by our LW members TechSew Ron: http://www.techsew.com/blog/needle-thread-chart/

Off topic but that video you made of your used Techsew 2900 was a work of art - well done!

Ron

[WhiteBuff]

Ok Guys

i had a #21 needle with 138 thread, that does not match the chart, so I'm changing to see the results, I'll report back

thanks Clint

[WhiteBuff]

Ok Guys

thanks for the info, went by the chart and added just a little tension to the top and she's rocking!!

the knot is dead nuts in the middle.

thanks Clint