Singer 45k25 stitch length

[Constabulary]

17 hours ago, Constabulary said:

Post pictures of your threaded machine please.

I quote myself and please post pictures of your lower tension unit please

[Sham]

@Constabulary @Wizcrafts

ok, now it is really messed up, I messed with everything, switched springs on the tension assembly’s, raised and lowered the needle bar, foot bar, ..the timing seems ok still, but it’s now making loops snd knots on smaller stitches. I think I probably can get it back stitching thinner leather with smaller stitches. But it doesn’t want to do anything with belt leather. Here’s some video links, I’ll see if I can upload photos too.

 

[Sham]

[Constabulary]

I can´t see anything wrong in the pictures. But to me the tension spring on the lower tension unit looks kinda weak (not sure though). See picture of my tension unit. The wire of the beehive spring on my tension unit is  approx 1.8mm in diameter (have to check to be sure).

All guessing but maybe worth checking:

Are you wrapping the thread around the tension pulley / wheel? Meaning thread comes from the top tension then wrap completely it around the pulley? This is from a GA-5 Manual but the circled picture shows it quite good.

 

Are you sure all parts of the lower tension unit are present? I looks like this:

 

Also - please check the 2 discs / washers in the tension. They should have a flat side in the center hole. That ensures they do not rotate when the pulley spins. If the flat side it rounded (happens with the time) and they rotate you have less friction between the components and that can cause less tension on the thread.  See picture:

 

Edited December 30, 2022 by Constabulary

[Wizcrafts]

In case anybody is curious why these old machines and current 441 clones have wheel disks on the bottom, it's a carry over from the days of waxed linen thread. The bottom roller didn't just roll with the thread. The big spring provides tension to resist rolling the wheel. While bonded/lubed thread moves semi freely around the wheel, waxed thread is grippy and that bottom roller actually has an impact on the top tension. That effect is much less with bonded and lubricated threads made today. But, if you wrap two full turns or more it does help fine tune the top tension. However, unlike the upper tension disks, that extra tension is never released when you need to pull the work away after the end of the stitch line.

[Sham]

Thank you @jimi @Wizcrafts @Constabulary @CowboyBob

@CowboyBob.. I just filed out the slot about 1/4” but the stitch adjuster piece still won’t go any lower? The motion of the feed dog looks like it would make at least 1/4” stitch, but it’s about 3/16” max, and then if I see uneven material it likes to shorten up

[Sham]

Machine is back at the mechanic, we’ll see what they say. Would be interested to hear what you say about the adjuster not going down further after lengthening slot though @CowboyBob? Also seems like it started with bigger stitches and got smaller after using for awhile