Singer 45k problem

[Tigweldor]

A whole new shuttle hook with bobbin costs small coin.

https://www.ebay.de/itm/365419392772?_

Get 10 new bobbins while you´re at it.

 

Greetings

Hans

Edited April 20 by Tigweldor

[Tigweldor]

Take a look at the routing of the top thread.

The last tensioning device does not clamp between two discs, rather the thread is wound around the wheel 1 1/2 times (important with that amount of turns)  before it encircles the metal dowel and then enters the take back spring.

That wheel is pressed by the spring pressure against a leather or felt washer.

If this soft washer is missing - wheel braking can not be adjusted properly - check that.

The take up spring has to work as well, to keep adequate tension on loose top thread - check that.

You may have to remove the wheel to check if the take up spring leg is in the proper location to produce adequate needed pressure.  You want that spring to be able to move freely under rather light pressure - not tight as hell - that defeats its`purpose. A fault often found due to an adjustment error.

Here are two pics from my Adler 4 and my Adler 5 - very close clones of the Singer 45K.

I usually use one size smaller than top thread for bottom thread - simply because I can get more "yards" onto the bobbin.

Actually a 160/23 needle is on the big side for TEX 20 Thread - better to use a 140/22 needle for that - especially if you are sewing fabric.

It is also nice to have quite a few bobbins ready to go - makes for a fast change if/when needed.

The bobbin holders are easy to make : drill under size holes in a piece of flat bar and press/hammer the cut to length round stock into place.

Takes no time at all if you use an aluminum flat bar and chamfer one end of the round stock on a grinder.

A wood pecker would of course use wood and proper length dowels - but I am into fabricating from metal - just personal preference cause I own a metal business.

 

 

Edited April 20 by Tigweldor
pics

[Bosko90]

Thank you for the detailed explanation and the attached photos! They’re always helpful. I think all of these things are set up the way you described, as I’ve gone through everything many times. That’s why it frustrates me even more — I really don’t know what else it could be. The shuttle hook isn’t that expensive, but I wanted to be sure it’s the actual issue before buying one, and whether this Chinese one would even be okay.
You mentioned the take-up spring. It seems quite strong to me, but it’s originally much stiffer than what we’re used to with other sewing machines. I tried to loosen it as much as possible. The only thing I’m not sure about is the correct setting for its height (or how long its range of motion should be).

 

 

[Tigweldor]

well, a real simple experiment would be to just run a thicker thread on your bobbin.

I all goes well then - you know that it is your bobbin holder tension spring that can not handle thinner string in its`present set up.

You can then take out the whole hook assembly, take out the little screw on the spring to remove and flatten latter out, so that the gap between it and the bobbin holder is diminished to nigh on zero.

 

 

Edited April 22 by Tigweldor

[Bosko90]

I can try it with a thicker one. But I can confirm that it can be adjusted so tight that I almost can't pull the thread out with my hand.