Cobra 4 Problems

[busted]

I am having mega problems getting proper tension my Cobra 4. It's been months of hours, trying and giving up. Going back to hand sewing and my old crappy flatbed machine. But I am thinking it might be more than just tension. There are times when I am able to wheel the machine by hand, so, the wheel IS turning, but the rest of the machine doesn't move. Ie, the needle (and everything else) stays put, near the top of it's rotation. Im wondering if this may be effecting the tension some how, maybe if something has come loose ? Im really at a loss...

http://www.youtube.com/watch?v=y8rBZfq29_E

(I posted about the tension problem yesterday, under a different user name, but thought I should instead start a new thread because it does seem to be more than just a tension issue and I didn't want to hijack that thread. I also for some reason wasn't able to sign in under my old name, so I had to make a new account)

Here are the tension issues:

I finally got it tensioned for one type of sewing I do, took DETAILED notes of the tension settings, then went back to try and tension the other way I sew, and it took hours and hours. Then I need to go back to the first way I sew, and my notes don't work. I can't get it tensioned back to the way it originally was. Am I missing something? It's wasting so much of my time, and a lot of materials. I've asked Steve, but his feedback hasnt seemed to have helped. I am hoping someone else with a Cobra or 441 clone can offer me some tips?

The first type of sewing I do is one layer of veg tanned about 6-7oz to one layer of chrome tan 3.5 oz. I use a 25 needle, with appropriate thread.

The second type of sewing I do is min 2 layers of chrome tanned, to max about 4-5 layers. I use a 21 or 22 needle, with appropriate thread.

I have got the machine to flawlessly sew both, eventually. But every time I try and tension for the other type of sewing, it takes me hours, days. Or longer. Or I give up (and thank God my old crappy machine still works well enough!)

In these photo examples, you can see how it varies between top tension is too strong, and then too loose. I CANNOT find the balance. (and yes, the top & bottom thread are the same thickeness & brand). It seems I cannot make a small enough adjustment, so it goes between too little and too much tension immediately. Sometimes I can get it to sew normal for 5-6 stitches, but then it always reverts to one way or the other (top is too loose or too tight)

I have adjusted bobbin tension as well. It seemed to like being just off the tightest setting for the thicker sewing, and as tight as possible for the thinner sewing. But so far its made no difference..

http://img824.images...69/tensionp.jpg

I borrowed a photo from the archives of LW to illustrate what I mean. It is not a very good blow up but you are able to see the thread coming down from the upper tensioner to the lower tensioner. Your machine does not do that. You need to put the thread on the back side of the tensioner then do the two counterclockwise wraps before going to the thread take up arm. There should be only one thread running through the retainer loop to the take up leaver. You are not allowing the lower friction disc to do it's job. Good luck.

[gringobill]

I am having mega problems getting proper tension my Cobra 4. It's been months of hours, trying and giving up. Going back to hand sewing and my old crappy flatbed machine. But I am thinking it might be more than just tension. There are times when I am able to wheel the machine by hand, so, the wheel IS turning, but the rest of the machine doesn't move. Ie, the needle (and everything else) stays put, near the top of it's rotation. Im wondering if this may be effecting the tension some how, maybe if something has come loose ? Im really at a loss...

http://www.youtube.com/watch?v=y8rBZfq29_E

(I posted about the tension problem yesterday, under a different user name, but thought I should instead start a new thread because it does seem to be more than just a tension issue and I didn't want to hijack that thread. I also for some reason wasn't able to sign in under my old name, so I had to make a new account)

Here are the tension issues:

I finally got it tensioned for one type of sewing I do, took DETAILED notes of the tension settings, then went back to try and tension the other way I sew, and it took hours and hours. Then I need to go back to the first way I sew, and my notes don't work. I can't get it tensioned back to the way it originally was. Am I missing something? It's wasting so much of my time, and a lot of materials. I've asked Steve, but his feedback hasnt seemed to have helped. I am hoping someone else with a Cobra or 441 clone can offer me some tips?

The first type of sewing I do is one layer of veg tanned about 6-7oz to one layer of chrome tan 3.5 oz. I use a 25 needle, with appropriate thread.

The second type of sewing I do is min 2 layers of chrome tanned, to max about 4-5 layers. I use a 21 or 22 needle, with appropriate thread.

I have got the machine to flawlessly sew both, eventually. But every time I try and tension for the other type of sewing, it takes me hours, days. Or longer. Or I give up (and thank God my old crappy machine still works well enough!)

In these photo examples, you can see how it varies between top tension is too strong, and then too loose. I CANNOT find the balance. (and yes, the top & bottom thread are the same thickeness & brand). It seems I cannot make a small enough adjustment, so it goes between too little and too much tension immediately. Sometimes I can get it to sew normal for 5-6 stitches, but then it always reverts to one way or the other (top is too loose or too tight)

I have adjusted bobbin tension as well. It seemed to like being just off the tightest setting for the thicker sewing, and as tight as possible for the thinner sewing. But so far its made no difference..

http://img824.images...69/tensionp.jpg

It looks like you've got the thread threaded through the top tensioner wrong, it's running through the guide just ahead of the top tensioner TWICE, forward and backward, oing in and then back out. I think that means you've got the thread wrapped through that tensioner twice, it's only supposed to go through it once, straight forward through , horizontal, between the discs then down to the bottom tensioner.

This has to be part of your problem.

You may have the thread properly routed through the bottom tensioner. It is supposed to go through the chrome thread guide then immediately back to the left, counter clockwise and around the smooth groove twice and then back out through the chrome guide and then through the black guide and up to the take up lever. It looks correctly threaded from that point on.

Now I'm wondering if all the "adjusting" to other parts of your machine hasn't exacerbated the problems originating from not having the machine threaded properly.

Also, if you have broken your thread at the needle or the bobbin you may have small bits of thread stuck in you bobbin mechanism, I have done that before and it will sure throw everything off. You may need to remove the exterior plate that holds the whole bobbin in it's cavity and make sure you don't have pieces of thread stuck in there.

Getting it machine threaded right should go a long way towards solving your problems.

Good luck!!!

Bill

[steve mason]

I do not have a cobra so take my advise with a grain of salt.

from looking at your video at the 1.51 second mark, your take up spring looks like it is set to high, try lower the the spring and see what happens.

Steve

[Steven Kelley]

I borrowed a photo from the archives of LW to illustrate what I mean. It is not a very good blow up but you are able to see the thread coming down from the upper tensioner to the lower tensioner. Your machine does not do that. You need to put the thread on the back side of the tensioner then do the two counterclockwise wraps before going to the thread take up arm. There should be only one thread running through the retainer loop to the take up leaver. You are not allowing the lower friction disc to do it's job. Good luck.

I'm definitely no machine expert, but I did notice how the thread was running through the thread guides twice as well. I have no idea if that would cause the thread to over tension and create an issue, but it would be worth a try to rethread. On my Cowboy 4500, I thread through the first thread guide, over the top of the tensioner, then down to the second tension disc (not around and up to the thread guide again). It wraps 1.5 times counter clockwise around the second tension disc (without going through the thread guide first), then goes through the thread guide, through the spring, and up to the take up arm. That's how Bob does it on his video.

Edited January 20, 2012 by Steven Kelley

[Cobra Steve]

Hello. If there is a problem with your machine please do not hesitate to call me. We may not get it right the first time, but we will succeed, one way or another. If we tell someone to do a certain thing to the machine, and we don't hear back from that person, we naturally think that the problem was solved. If not, please call back and we will try something else. We are always willing to help with your machine, and other machines as well. I have never been upset with anyone that I have talked to regarding service, it's not my style. Please call me at 1-866-962-9880, thanks, Steve

Edited January 20, 2012 by Cobra Steve

[Spinner]

With the hand wheel properly tightened, is everything now moving in sync? Check the other screws on moving parts you can see. Make sure screws are not loose. But, make sure moving parts are not binding.

Let's work on the top thread problems.

Grab a kitchen funnel, or go to an auto parts store and buy an oil funnel, which is just slightly bigger on the bottom than the spool of thread is on top. Make the spool into Tin Man,with the thread feeding out the long narrow spout of the funnel. Feed it up, through the thread guide hole and pull the thread. See if it unwinds from the spool, feeding through the tornado of the funnel spout. If so, let's continue wit the Tin Man concept. If not, remove the cap and we'll try something else.

Whether the funnel trick helps or not, feed the top thread from the hole in the top guide bar through the top hole in the post on top of your machine. twist the thread against the direction of any coils, to loosen it as much as possible. Now, thread the rest of the way as shown in the instructions.

Choose the correct needle and thread combination for the leather thickness and hardness you want to sew. That might be a #25 or #26 needle for #277 thread, top and bottom, depending on the hardness of the leather. Don't try sewing thick nylon thread into thin leather. This requires a different, softer type of thick thread that you are using.

Using a larger needle than required sometimes makes it harder to balance the position of the knots than if a smaller needle is used. Too small of a needle may cause the knots to stay on or near the bottom no matter how hard the top pulls. Try different size needles with your thread and stick with the ones giving the best, repeatable results.

Make sure that the bobbin spring presents smooth friction for the bobbin thread and make sure the bobbin is loaded to feed backwards to the slot in the case. Remember what I told you last night about checking the bobbin for any starting thread that may be looped out of the little hole and around the top of the bobbin disk. These leftover threads are grabbed by the spring inside the bobbin case and cause tension variations.

Make sure the top thread is not twisting around anything it should be passing through. Set the tension adjustment around the middle of the top disk adjuster. Sew a few inches and see what you get. Adjust the top adjuster for the best consistent result.

Hints:

If both top and bottom stitches are loose, tighten both top and bottom spring tensions. If both are dug into the leather too far, loosen both tensions. If the knots are all on the bottom, tighten the top tension. If the knots are all on top, loosen the top tension. If the knots are all over the place, tighten the bobbin case spring and try again to balance the thread.

Finally, change to a different brand of thread and try again. If you can't do that, spray the spool with silicon, or place it into a can of pure mineral or sewing machine oil for a few minutes. Dry off the excess lube and try using your lubed thread. If this helps, consider buying only pre-lubricated thread (e.g.: http://www.tolindsew...com/thread.html).

Another thing that just came to me: Make sure your thread doesn't say RT, or right twist! Our single needle sewing machines require left twist, also known as LT, or Z twist.

Wiz,

Just wanted to say thanks for this, you answered a few questions I haven't had a chance to post yet.

Chris

[particle]

Different machine, I know, but they're basically the same from what everyone says. Look at this video and make sure you threaded it just like they did.

[Mike Craw]

KND,

CALL STEVE!

I bought a Cobra 4 less than a year ago and I couldn't make it sew no matter what I did. Steve spent hours with me on the phone going through various re-threads, tests, and fixes. Finally he asked that I send the head back to him and that he would pay the shipping himself. When I got the machine back, it sewed like a dream. I'm still not convinced that it wasn't something I was doing wrong, but Steve assures me I'm not as incompetent as I think.

If Steve had reason to be short or disgusted with anybody, it was me. I figured that I was too old to learn a new trick and that I should just go back to hand sewing like I'd done for the past 25 years. Steve never got out of patience or lost his sense of humor (although I came close a couple of times.) He stands behind his products and will make it right regardless. One of the nights we spent an hour on the phone was when he called me out of the blue on a Saturday when he could/should have been doing something with his family.

My Cobra now sews better than I could have imagined and I'm working on raising my abilities to meet the machine. I can't say enough about Steve and his organization. There are alot of folks on here who can help you, but Steve is your best option. He knows that machine as well as anyone and he really lives and breaths service. Call him.

Hope this helps,

Mike

[Cobra Steve]

Hi KND. First of all your hand wheel is on backwards, please turn it around so the bolts are on the outside.This could cause the belt to be on a severe angle causing a drag on the machine. If you are using a #25 needle to sew 10-11 ounce leather, the needle will make too big of a hole for that thickness. When you say you are using the appropriate thread, does that mean for the #25 needle, or the thickness of the leather? You should be using a #23, or at the most, a #24. The thread size should be 207 top and bottom. You may have to re-calibrate the top tensions and/or the bobbin tension as well. You will have to start from scratch, but it should solve your problem. This is definetly a tension problem either caused by the wrong needle/thread combination, or calibration, but either way, it will be a simple fix. I know that we discussed this a while back, but when I didn't hear back from you, I thought that the problem was solved. Please contact me for more instruction on how to calibrate your tensions. If anyone else is experiencing a similiar problem, with any machine, please call me at 1-866-962-9880 and I will walk you through the calibration procedure. Thanks, Steve

[Trox]

Hi KND, The guys are right, your machine is threaded wrong.

Did it fix the problem?

Hi Cobra Steve, it is a good Idea with a video on troubleshooting treading an simple stuff on your website (youtube), This are issues happening to all brands of sewing machines.

Trox