Problems Sewing Leather With My Machine- Advice?

[rmr]

I make shotgun cases and range bags using either latigo(5/6oz) or bison hide(8/9oz). I have a cobra 4 machine that I have had about 3 years now and it has always functioned well. I use 277 thread and a # 25 needle. The tension on the machine was set before I got it and I have never messed with it since it was set for the thread diameter I use on all my projects. The machine is oiled regulary. The thread is passed through all eyelets and tensioners correctly ( I saw the previous thread where someone was having problems possible due to running thread through guides 2 times)

My problem: I am finding that as I sew - often the needle will stop, on the down stroke, as it is going through the leather - the fly wheel turns but the needle wont advance through the leather( or goes only partially through it) - almost like the leather is stopping its advancement. Sometimes I can rotate the wheel by hand forward and backwards to get the needle to penetrate the leather. Depending on what Im going I may be sewing 2 -4 layers of leather together ( total thickness of all layers 1/4-1/2" generally) - which this machine should handle. Sometimes the machine gets hung up on 2 layers of leather other times its on the thicker 1/2 " stuff. I tried putting new needles on- same thing , and the needles always seem real sharp. I have gotten to the point on some of the thicker pieces that I will use a pricking iron to creat a hole spacing pattern and then use a hand awl to partially go through the lether layers and then run it through the machine - which often hepls.

The things I have been wondering about:

1) Is this a tensioning problem??? When it works the stitching always looks fine

2) is this a machine problem???

3) I glue using Barge cement- I have wondered is the glus getting to hard and creating a barrier for the needle to pass through???

4) Is the bison hide just to tough for the neddle to go through?? Even though I have had times it does the same on latigo

Any ideas out there??

Thanks RMR

[Wizcrafts]

snip

My problem: I am finding that as I sew - often the needle will stop, on the down stroke, as it is going through the leather - the fly wheel turns but the needle wont advance through the leather( or goes only partially through it) - almost like the leather is stopping its advancement. Sometimes I can rotate the wheel by hand forward and backwards to get the needle to penetrate the leather.

snip

It sounds like the same problem another member just had: a loose flywheel. Tighten up the two screws that secure the wheel to its shaft. Then tighten the pulley and motor belts a little more.

It is possible that the bison skin is stressing the mechanism somewhat. But, if the wheel it fully tightened and the belts don't slip, the motor should force the needle to penetrate all layers. Just yesterday, I sewed through1/8 inch of plastic taped to 12 ounces of Latigo with a Cobra 4, using a #25 needle. Had to tighten the upper belt by lowering the pulley all the way.

[Cobra Steve]

Hi Bob, yes, tighten the belt. After 2-3 years, the belt might stretch a little by lowering the speed reducer. Thanks, Steve

[rmr]

Hi Bob, yes, tighten the belt. After 2-3 years, the belt might stretch a little by lowering the speed reducer. Thanks, Steve

Hi Wizcrafts and Cobra Steve

Thanks for the help and recommendations- I hadnt thought about that as a possiblity. I will go home after work tonight and make some adjustments to the belt. I will let you know how everything goes - Im guessing that is exactly what is going on.

RMR

Again Thanks for the prompt reply and advice!!!!!!

[rmr]

Thanks Wizcraft and "Cobra" Steve

I lowered the speed reducer about 1/4" & re-tightened up the 2 bolts holding the flywheel to the shaft- I THINK THAT WAS THE TICKET!!!!!!!! It now seems to be doing just fine. I feel a litle embarresed that I couldnt figure that one out on my own.

RMR

On a side note: I wanted to personally thank Steve at the Leather Machine Company who after reading my post this morning, sent me a note as well as personally called me ( he initiated the call not me) to walk me through trouble shooting my problem. Now that is what I call customer service that you dont see every day. I should have just called Steve first on this one as he knew exactly what to do. I have purchased this cobra 4 machine, the electronic needle positioning system and a beatifully refurbished Pilgram leather splitter from Steve over the past 3 years and have always felt that he is a stand up guy, takes great care of his customers not only when they purchase a machine from him, but whenever they need help even years after the sale. He is always very friendly, helpful and knowledable about his products as well as other leather machinery that he may not have but will find it for you ( thats how I ended up with the Pilgram Splitter- I had searched near and far for months trying to find one on the internet and always came up empty handed. I was ordering an attachment for my Cobra machine and just happened to mention to Steve about looking for a leather splitter - 2 days later out of the blue he called me at work and he had gone out on his own and located 2 splitters and gave me the specs on each one- needless to say I bought one). When I need a piece of equipment for leather working- Steve has been, and always will be my go to guy first.

Anyone out there looking to get a leather sewing machine- I would personnaly recommend Steve and his compnay in a New York minute - and that means a lot comming from a Texan:yes:

Steve I owe you a beer and a staek for help on this one

RMR