Cobra Class 4 Shuttle Timing Issue

[iknowthisguy13]

I cannot adjust the timing on my sewing machine. I am sure I am doing something wrong. When the needle starts rising that bolt is not accessible as that part of the linkage is turning towards the back at that point. I am a total newbie, just finished setting up the machine yesterday. Does altering the stitch length alter the timing of that linkage? Any advice would be greatly appreciated.

[CowboyBob]

What is going on that you think you need to work on it?

[iknowthisguy13]

The needle is hitting the bobbin.

[CowboyBob]

Did you change the needle?If so double check that it is pushed all the way up.

[iknowthisguy13]

Confirmed. The needle is all the way in.

[CowboyBob]

Ok,now you want to turn the machine ( the handwheel) towards you & when the needle gets all the way down & right as it starts to go up the shuttle also does the same, it goes all the way back & should start to come forward @ the same time the needle goes up,check & see if this is happening?

[Wizcrafts]

Did you buy the machine brand new, from Leather Machine Company? Or, was it a used machine from a private seller?

If new, you can call the company tomorrow, during normal business hours on the West Coast.

There are two basic places where the timing can be adjusted. One is the height of the needle bar, which is secured by two Allen screws, inside the faceplate. The other is the positioner for the hook, which is accessible through a round covered hole in the base of the machine, on the right-front side. It is safer to try raising the needle bar than to dink with the inside the body mechanism, without expert guidance.

All timing adjustments should be made with the stitch length/direction lever set to the zero movement position. This balances the range between forward and backward feeding.

Also, since Bob is responding on his day off, you are under expert guidance already.

[iknowthisguy13]

Bobbin starts coming back up as the needle where the feed dog currently. This is the improvement guessing at the timing made since I can't set properly.

I bought it new from Springfield. The 6 mm hex bolt is what I can't get to when the needle starts rising. Thank you for the zero movement rule.

Should I be positioned at the start of the bevel in the hook or at the tip when 3/16" up from bottom?

Ok see the actual hook now. I think the timing is set right, but now I am not engaging the bobbin thread.

[Wizcrafts]

Okay, you seem to know about the hidden bolt. Here is what I do when I have to adjust machines like yours. Rotate the hand wheel until you have direct access to the bolt. Loosen the bolt, than lightly go clockwise to give it a little grip, but not a locked down tightness. Rotate the wheel until the needle has gone all the way down and comes up about 3/16". Stop rotating. Grab the shuttle and try to move it in the direction that places the point of the hook about 1/8" above the eye of the needle (with stitch lever at zero). If it won't move, place something soft, like a pencil eraser, against the appropriate edge and tap lightly to reposition the hook. Once you get the hook positioned, rotate the wheel until the face of the bolt is accessible and tighten it down all the way.

Be careful not to damage the hook!

Test the timing in forward and backward. If all is good, call it a day and start sewing.

Edited June 28, 2015 by Wizcrafts

[CowboyBob]

The point of the shuttle should be @ the needle when the needle rises about 3/16",make sure you turn the machine in the direction it runs.

[Wizcrafts]

Thanks for the correction Bob. It's my day off and the machine is 4 miles away from home.

The whole deal is to have enough rotation between BDC and the arrival of the pointed hook to have it pick off the loop that forms on the right side of the needle. There is a best position for this to happen.

Edited June 28, 2015 by Wizcrafts

[iknowthisguy13]

So is the bolt supposed to be on the back or am I one of the lucky ones? What newbie mistake is not allowing the bobbin thread to be picked up? And thank you for the tapping trick!

[Wizcrafts]

So is the bolt supposed to be on the back or am I one of the lucky ones? What newbie mistake is not allowing the bobbin thread to be picked up? And thank you for the tapping trick!

Yeah, shuttles are expensive to replace. I know.

The bolt is where it is! That's why I loosen, then finger tighten it, so I can turn it with my fingers (in theory!). The eraser protects the shuttle when you need to hit it to move it.

[iknowthisguy13]

I give up. I can't get the needle thread to engage the bobbin thread at all now.

[Wizcrafts]

I give up. I can't get the needle thread to engage the bobbin thread at all now.

Set the hook so it intersects inside the scarf of the needle, a bit over the top of the eye, after it has raised about 3/16" from BDC, with the stitch lever at zero.

Next, pull out the thread and rethread the machine. Do not skip any part along the path. As experienced as I am, I have forgotten to go through the take-up lever once or twice! No take-up, no sew.

Make sure the thread path is unobstructed from the spool onward. It must flow freely until it gets to the top tension disks. It must sit all the way down between those disks to maintain top tension. The little steel loop on the lower right of the disks can be repositioned slightly to get the thread well into the disks. From there, go down and once fully around the lower disks, the through the guide over then, then through the loop in the "check" spring* attached to that assembly. From there, up through the take-up lever, down through the clip guide, the wire guide, and the hole above the needle mount, then through the eye of the needle, from left to right.

Before testing, lift the presser feet with the foot lever, they should go up high, at least 7/8" or higher (mine lift a bit over 1"). Pull on the top thread at the take-up lever and ensure that it flows freely. Lower the foot lifter and try pulling again. It should be hard to pull the thread, meaning you have (adjustable) top tension.

Load bobbin thread counterclockwise, through the slit in the bobbin case. Adjust the spring tensioner for a modest pull on the bobbin thread. It should neither be jammed or totally loose. A smooth steady pull is best, generally speaking. Rotate the hand wheel toward you from the top, in a counterclockwise direction, manually (depress the speed pedal slightly to free the internal brake, if your motor has one). If you rotate the wheel the wrong way the machine will not sew!

Watch as the needle goes down and starts back up. The hook should intersect the needle above the eye and you should see a loop form to the right. The hook should then pick off the loop as you continue rotating. the wheel.

* The check spring's job is to maintain tension on the top thread as the take-up lever moves down. It should hold that tension until the needle contacts the top of the material. This is to keep the needle from piercing the top thread due to too much slack. OTOH, it must give up and stop before the needle starts back up, after BDC. Otherwise, no loop will be formed. The check spring is set by the dealer before the machine is shipped and is usually spot on.

Report back. Over.

Edited June 28, 2015 by Wizcrafts

[Art]

Ok,

Sounds crazy, but is the needle in correctly, by that I mean slot on left, scarf on right? I know the guy that sets those machines up, and it should run like a rabbit right out of the box.

Art

[iknowthisguy13]

Rethreaded the machine, all the tensions check out, the hook intersects the needle as proscribed. Needle is in all the way (new needle) long groove on the left. Small loop forms and does nothing.

Bobbin threaded and installed correctly. tension seems appropriate there too.

[Wizcrafts]

There is a movable stopped under the check spring, secured by a flathead screw. Loosen the screw and adjust the metal stopped so the check spring stops a little higher up. Try again. The standard position is the arm of the spring faces more or less horizontal.

Approximately how much upward travel is your needle making before the hook arrives over the eye?

[Wizcrafts]

As I pointed in before, make sure you are rotating the wheel towards you from the top, which is in a counterclockwise direction on the shaft, from the read of the machine. Modern sewing machines almost always rotate CCW. They will not pick up the bobbin thread or form stitches if you turn the wheel the wrong way. It is an easy mistake for a first time sewer to make.

Edited June 28, 2015 by Wizcrafts

[iknowthisguy13]

3/16" of an inch to the best of ability. I am turning the wheel in the correct direction. Is the loop that forms suppose to drop down and hook immediately below the hook that forms it? If so, this isn't happening.

[iknowthisguy13]

Is the outer race supposed to be really snug? I was under the impression from the Al Bane video that it would fall off with the screws removed. I had to work it off with a screw driver.

[iknowthisguy13]

Going through the Leather Machine Co video now. Already adjust the dragon centric cam.

[iknowthisguy13]

And the timing cam...

[iknowthisguy13]

OK, I have tuned everything that can be tuned and still no joy. Top thread does not go around the shuttle. The loop still forms then nothing.

[iknowthisguy13]

And the directions are now reversed. Goodie.