Cobra 4 Inconsistent Thread Tension

[Red Cent]

"Once turn around the bottom post is okay, as long as you aren't using it to add much more top tension. One turn also makes it easier to extract the thread when you fully lift the presser feet with the floor pedal. Note, this means that the top tension disks do most of the work on the top thread."

The turn around the bottom post is the side tension pulley/wheel with springs, right? Since that would reduce tension on the top thread I would probably need to increase tension with the top adjustment discs, right?

I can easily fix the lube pot to create that straight line feed. If I try it, should I put the lube pot thread level with the eyelet?

[dirtclod]

I've sewed with the pot on top for 20 years and never had a problem.

BTW: I believe the Cowboy machine would work with the lube pot. One time around the wheel would not cause bind. I guess the post on the Cowboy is added tension and does away with the double wrap. Am I close in my observation Cowboy Bob?

Why does it make any difference between a Cowboy and a Cobra machine ? Their the same machine just different colors.

[CowboyBob]

No,always wrap around the lower tension 1&1/2x if you don't you will(probably) get eratic tension.The way the lower one works is it acts like a brake & the thread needs to be around it like I said so the thread is gripped by the pulley so it can spin.The lower pulley (aka tension) also needs to spin to work if it's overtighted & doesn't spin it will give eratic temsion too.So that is why you mainly need to always adjust the top one as or when needed.It doesn't hurt once in a while to take the lower one apart & put oil on the shaft so it can spin.The old 7 class Singers use this same type of tension & I've seen quite a few of then with wornout holes in the pulley.Of course some of these could be 40-70 yrs old but I think alittle oil might of prevented it.

[Red Cent]

This is a video showing how to thread a Cobra 4.

This a video showing how to thread a Cowboy 4500. Dirtclod, my Cobra does not have the post with holes on the top of the machine. And Cowboy Bob, you are correct about the side tension wheels. However, on the top tension wheel the Cowboy does not need to go around the top disc/wheel but simply heads straight down to the side tension wheel. On the Cobra, you are told to go almost all the way around the top wheel and come back out through the eyelet and then down.

[dirtclod]

If it has a place for a post i would get one. Heck i might drill and tap a hole if it doesn't have a place for the post to screw into. When you thread it i would try going through the thread guides one time and straight down on the top tension disks and one and a half like Bob shows. In my eyes you have nothing to lose trying that to see if it helps.

[Red Cent]

If I put a post on it so that I would not have to wrap the top tension wheel, I am creating friction/resistance someplace else. You're right, nothing to lose. And I may try it.

Looking at the different thread paths, it seems the tension is equal with different methods.

[dirtclod]

On my machine a Pro 2000 i run the thread straight through the post no wrapping. Then through the wax pot through the guide to the tension disk. Then down the second disk and go one and half times through the guide then through the spring and up through the take up lever and on down to the needle. I've done that ever sense i had my machine and it's worked fine for 20 years.

You should be able to change the angle of the pot to where it's in line with top tension by adjusting the screw that holds the pot on.

[Red Cent]

It would be simple to "scab" a bar with two holes to move the lube pot over in line. Actually, you could move it over and drop it to be more of a straight path.

One of these days, I will get it dialed in. I just bragged about removing the pot and it sews well. Now it has started to skip stitches. I put the lube pot back in the "loop" and it is doing OK. Go figure.

If the Juki, Ferdco, Cowboy, are copies, then are the differences so different that threading requirements would be so different? Having read a little on the clones, seems as if a couple of Japanese companies make most the machines. As I told Steve, frustrated as ......but I ain't giving up.

I find it odd that you don't see anyone on here complaning about the Cowboy 4500. Or the Ferdco Pro.

Edited August 20, 2013 by Red Cent

[Cobra Steve]

Hello all. We have discovered that with some threads, the bonding agents affected the travel of the thread through the main tension assembly. Some threads had a tendency to slip out of the tension, but once we brought the thread back to the thread guide, no matter what thread we used, the thread would never slip out, allowing the customer to use whatever brand of thread they chose. As for the thread post that screws to the top of the machine, we found that in most cases it added to much tension, (I discovered this when I worked for Artisan) and we decided to remove the thread post. When we did, we had better consistency when it came to tensions. This does not mean that everyone will have the same results, but we did. Whatever works. Thanks, Steve

[Red Cent]

"We have discovered that with some threads, the bonding agents affected the travel of the thread through the main tension assembly. Some threads had a tendency to slip out of the tension, but once we brought the thread back to the thread guide, no matter what thread we used, the thread would never slip out, allowing the customer to use whatever brand of thread they chose."

I am not clear with this. Please be specific with the hi-lighted words. Just to make sure we communicate.