Cobra Class 4

[aldenorange]

All,

I'm having a few issues with my cobra class 4.

1. I took the hook out to inspect it after a needle shattered. When i put it back in, the top thread wont get around the hook for some reason. It gets stuck on the back side of the hook I have attached a picture for reference. Top thread is brown. In the picture i haven't screwed the screws all the way down, but even when i do, it doesn't clear the hook.

2. When i back stitch, it doesn't go in the same hole. The length of backstitch is much longer than the forward stitch. If anyone knows how to fix that, i'd be very grateful.

Thanks for the help!

-Alden

Edited November 1, 2015 by aldenorange

[Red Cent]

Now that is a new one. I am watching.

[Wizcrafts]

Take the shuttle out again and polish the trailing edges. Feel the race, driver and bobbin case for any nicks and polish them out as well.

When you reinstall the race plate, leave the spring loaded screws backed off about 1/2 turn each.

Oil the race.

The reverse not matching forward is a compound error with multiple possible fixes, listed below in order of simplicity/difficulty.

1. Adjust the inside presser foot position so that its bottom meets the top of the leather at about the same time as the needle begins to poke the leather. I know this doesn't sound like a fix, but it can be. Use the large hex driver that came with your Cobra to loosen the hex head screw on the left rear of the head, where the arm transfer motion to the presser feet. Once loosened, you can move the inside foot by hand to match the position of the needle. Tighten the screw afterward.
2. If the above has no effect, or not enough improvement, loosen the top screw on the stitch lever plate and place a washer behind the plate, then tighten the screw back down. This moves the top of the stitch length plate away a little and shortens the stroke in reverse.
3. There is a major stitch length/position adjustment available inside the front access port and another important bolt inside the rear access hole. Consult the paperwork that should have come with your machine. Or, wait until you can get in touch with Steve to talk you through it. A wrong adjustment will make things much worse.

[aldenorange]

All,

So in typical fashion, i figure out the first problem right after posting. The tension wasn't correct, not allowing it to pull heavily enough to get it past the back of the hook.

Wiz,

I think the issue was the inner foot not being straight. It kept going diagonal a bit with the back stitch. I straightened it and it seems to be a bit better.

Thanks for the quick responses!

-Alden

[Art]

First thing (every mechanic knows this but it is so simple we just don't mention it) you must do is find all of the broken needle. After that, follow Wiz's advice.

Art

[TinkerTailor]

First thing (every mechanic knows this but it is so simple we just don't mention it) you must do is find all of the broken needle. After that, follow Wiz's advice.

Art

Especially if it gets in your eye.. For those of you out there not a blind old fart with bi-focals already, safety glasses are a good idea. Pirate patches went out of style last night.

edit: in no way am i excluding myself from the blind old farts, nor am I admitting it......

Edited November 2, 2015 by TinkerTailor

[Wizcrafts]

So, ti

Especially if it gets in your eye.. For those of you out there not a blind old fart with bi-focals already, safety glasses are a good idea. Pirate patches went out of style last night.

edit: in no way am i excluding myself from the blind old farts, nor am I admitting it......

So, a Tinker Tailor Soldier Spy neither admits not denies knowing anything about it!