Help with Adler 105-27

[IMK]

Hello everyone!

First time , I've read the rules but if I am missing something let me know!

I've had leatherworking as a hobby since 2022 now, and I've been enjoying it a lot. After 3 years of sewing by hand I wanted to look into a sewing machine. After doing some research and looking around locally at what was available (the more crucial to the search of the two), I found and fell in love with this Adler 105-27. But as any young man who has fallen in love. I am not sure how to get it to work. I have watched videos and read posts on how a sewing machine generally works, so I am not completely out of my depth... Sadly I seem to have chosen amachine on which there is not a lot of information online. I've found the manual online, and read through some posts about the 105 but was unable to come up with a solution by myself. I did read that the 205 and the singer 45k are models similar to the 105, but am not sure of that enough to use the manuals for the fixing of my machine.

The problem I am running into is that my top thread seems to be breaking after a couple of stitches (2 or 3). I've lowered and increased the upper thread tension, exchanged the needle. But to no avail.  I've included a slowmotion video of the side of the machine whilst stitching and a couple pictures of the machine in question. In the video the top thread seems to be jumping around a lot during sewing. Not sure if this might be the culprit.
If anyone is able to offer me any advice I would be very grateful! If there is any information that I have not included let me know.

Thanks in advance!

 

 

 

Video of stitching in slow motion, shot (poorly) on my Iphone: 

 

Edited Monday at 07:56 PM by IMK
Forgot to add topic

[friquant]

You may be able to learn what is out of adjustment by slipping the belt off, and hand wheeling slowly. If there's enough force generated to break the thread, you'll likely feel that at the handwheel and you can see what is binding or yanking. It may be easier to feel if you are stitching somewhat thinner material. 

I'd also be interested to see what the hook to needle timing is.

Beautiful old machine 😍

[IMK]

On 7/15/2025 at 4:33 AM, friquant said:

You may be able to learn what is out of adjustment by slipping the belt off, and hand wheeling slowly. If there's enough force generated to break the thread, you'll likely feel that at the handwheel and you can see what is binding or yanking. It may be easier to feel if you are stitching somewhat thinner material. 

I'd also be interested to see what the hook to needle timing is.

Beautiful old machine 😍

Thank you, I'll give it a try this weekend. And make a video and look at the hook to needle timing!
If the hook to needle timing was wrong, how would I go about adjusting it?

It is indeed a beautiful old machine, very happy with it. I wasn't prepared for its weight when I went to pick it up from the seller 😅, my arms hurt for days 😆

Edited Wednesday at 05:52 AM by IMK

[Constabulary]

what I have noticed so far is:

The needle plate / throat plate seems (!) to be modified and an the needle plate is missing material (or a deflector cover) left side of the roller foot / feed dog. Maybe this is something custom made but I can`t tell from the pictures. Not sure why this is but it is / looks unusual IMO. BTW - the original 105-27 came set up as jump foot machine and not with roller foot. So seems your machine has been modified quite a bit. But this could be custom made and I don´t want to judge this but it is not how the machine left the factory.

In your video it seems (!) that 2 thread guides are missing, one on the needle holder (seems to be ground off somehow) and one on the face plate. Therefore the thread is "bouncing" around. This may affect the loop forming and that could cause thread breaking.

EDIT I:

Some one has modified the shuttle race as it seems. Your is held by 2 screws (maybe they are too tight???) but originally it has a U shaped sheet metal leaf spring that is holding the shuttle race in place. But again - could be a modification a customer asked for. Hard to tell w/o knowing the history of the machine.

EDIT II:
some pics of how the thread guides look on an Adler 104

 

Edited Wednesday at 08:16 AM by Constabulary

[Constabulary]

  

1 hour ago, Constabulary said:

EDIT I:

Some one has modified the shuttle race as it seems. Your is held by 2 screws (maybe they are too tight???) but originally it has a U shaped sheet metal leaf spring that is holding the shuttle race in place. But again - could be a modification a customer asked for. Hard to tell w/o knowing the history of the machine.

just figured I could be wrong with that - just found this thread regarding a 105-27 and it seems to have screws in this subclass. 😉

 

[IMK]

This is some great information! I already found that thread and read through it, but wasn't able to spot the differences myself. I wonder if it would be possible to source parts for the missing pieces, I'll have to look around for that. Thanks for the help!

UPDATE on the machine, I seem to have been able to fix the thread from breaking. I will to try to explain, but to be honest I had outside help and have trouble grasping the situation myself. The clutch motor had a perilex plug (not sure why). I changed this to a standard 16 amp high current plug. I was unsure about what the effect would be on the machine but figured I'd have to make it work anyhow, since I don't have a perilex wall plug. I kept working with the machine this way, but realized that I should've checked way earlier if we attached the new groups the right way. Yesterday we switched two of the groups and voila, the machine was stichting!

 

Now as you can see, while it is sticthing the lower thread tension is too low. So I went to adjust it. Interestingly the hook shuttle that is in my machine is also not the original (or the 27 subclass had a different one by design.) 

The original manual shows screw 47, that has to be loosened before screw 48 can be adjusted to increase or decrease tension.

The manual:                                         My shuttle:

 

Everything seems to be going well thus far, sadly as I went to adjust the screw it broke 😔. Maybe I used to much force or it was just because of old age, but I had a small heart attack when it happened...
So if anyone has any idea where to source replacement for that specific screw or just the shuttle, I would love to know!