Cobra 4 thread issue

[speedybri]

Hello.  

I got a cobra class 4 machine recently and it was stitching just fine. Even with linen thread.  However wanted to add a wax pot since I use primarily linen thread.  Mostly 4 cord barbours.    After I added the wax pot, now it doesn't seem yo want to stitch well, sometimes not at all.  Adding the wax pot with silicone lube is literally all I changed.   Does anyone have any experience with this? Or know whats going on?   I tried adjusting the tension, etc... it seemed to help a bit but not much.   The machine is new to me so I have had tne chance to mess with it alot.   Just thought I'd put this out there for some feedback.    

Thanks for any and all help.   

Brian. 

[Wizcrafts]

The wax pot causes the thread to make a shape turn down and then up. Wetting linen thread weakens it when it is under stress. Linen thread can't handle that sharp angle when it is wet. The Cobra was not designed to use linen thread.

The best sewing machines that are designed to use linen thread are needle and awl harness stitchers, like the Union Lockstitch and the Campbell-Randall Lockstitch, as well as the Puritan Chainstitch, and the Landis 12 series curved needle and awl shoe sole stitchers. All of these machines have gentle turns for the thread and use rollers in the wax pots, which typically contain bees wax, not silicone lube.

Should you attempt to run liquid wax in your wax pot, it will gum up the tensioners and the eye of the needle. The 441 machines are meant to use bonded synthetic thread.

[Handstitched]

6 hours ago, Wizcrafts said:

The Cobra was not designed to use linen thread.

I have never used linen thread, but thats is something new I have learnt today   

HS

[speedybri]

I called the folks at leather machine Co before I purchased the machine and they said I could use linen thread as long as I used a wax pot.  I also had asked a similar question here a while ago and the response I got here seemed tk indicate that too. So now I'm confused.  I had a Campbell randall in my shop a friend was nice enough to let me use for a while and I didn't have the time to mess with it. I needed a simpler machine.  So I got this cobra under the understanding that I should be able to use linen thread as long as I used a wax pot.   Now I'm very confused.  Lol.  I run cotton thread through my Juki 341 and it does just fine

Edited November 27, 2023 by speedybri

[kgg]

1 hour ago, speedybri said:

I called the folks at leather machine Co before I purchased the machine and they said I could use linen thread as long as I used a wax pot. 

You may want to check with Leather Machine Co. for how you need to set the machine up. Also attach a couple of photo's of how you have threaded the machine as they may recommend a different method of threading. The Cobra clones are threaded differently then the Juki TSC-441, the Cowboy or the Techsew. Here is a topic with photo's of how the top thread is threaded differently on these machines. You could try and thread the machine like a Juki TSC-441 and see if that works.

1 hour ago, speedybri said:

I run cotton thread through my Juki 341 and it does just fine

Different thread path, different tensions, different number of top thread tension points.

Also what size of needle are you using in the Juki 341 with what size of thread and what are size thread are you using in Cobra with what size needle?

kgg

 

[speedybri]

Hi.   Thanks for the help. I really appreciate it.  Right now I have barbours 4 cord linen thread in the cobra class 4.   I have silicone lubricant in the wax pot.  I don't honestly care what lube I have to use as long as I can use linen thread in the machine. The silicone lube seems to have made it worse honestly.  I actually was stitching with linen before I added the lube. I wad told the lube would add strength and if I was using linen thread I needed to use lubricant. .  For the needle im using schmetz 200/25

Not sure what the thread size I'm using in the juki 341 is. It says 16 on the spool. Lol. I've been getting it for years at a local fabric shop.   I'll attach a photo.  The needle is a schmetz 140/22. I only use that for lighter leather. Like 3 oz and below.    

[kgg]

8 hours ago, speedybri said:

Right now I have barbours 4 cord linen thread in the cobra class 4. 

 

8 hours ago, speedybri said:

Not sure what the thread size I'm using in the juki 341 is. It says 16 on the spool.

From what I can gather and I don't know much about linen thread the #16 that you are using in the Juki 341 is a 3 cord or 4 cord which has a thickness of 0.56 mm or 0.65 mm thread equal to about:

i) #16, 3 cord just a touch over V207 which means it should use probably a#25 needle

ii) #16, 4 cord just a touch under V346 which means it should use probably a#26 needle.

So since you are using it in the Juki 341,

i) I figure you are using #16, 3 cord as that machine isn't rated to handle a #26 needle or V346 thread.

ii) The #22 needle is good for V92 thread or about a #30 linen thread.

iii) The #25 needle you are using in the Cobra is good for V277.

If you can read the information off the barbours thread spool to get a size or if you could measure the diameter of the thread someone more knowledgeable could suggest a proper size needle that may work. The Class 441 machines, Juki or clones are only rated for thread up to V415 or thread with a diameter of about 0.28" or .72 mm.

kgg