I am new here and this is my first post on Leatherworker.net
Its been a few month now that I am reading with great interest leatherworker.net forums as it is such a fantastic ressource !
I am in a process of retraining and will start a six month traineeship provided by a professionnal. The goal is to obtain a certificate of profesionnal competence (french diploma), the key to start to work by myself.
I will mainly learn traditionnal hand sewing techniques but because I know sewing machines are being also very usefull with leatherwork I have bought two second hand machines, based on what I have learned here.
The first one is the light one, it is a singer 31k15, an allrounder for textiles and for light and supple leather. It was in perfect condition, bought it for 35$ complete, with table and motor to it's first owner who stopped sewing because of her age.
I have cleaned it, oiled it because it's been kept in a garage since "a while". Original motor was a racing beast and I haven't been able to tame it, despite all my efforts. I then bought a 550 w chinese servo motor and it is now perfect ! I really love it and it works like a charm :
The second one should allow me to sew heavier leather, it's a walking foot, a Mitsubishi DU-105 22 (large hook/bobin). It's I guess an old machine, and according to what it looks like, a heavy worker for years, but I did not payed much for it, about a 100$, with table and motor :
According to what I have learned, it's a Juki lu-563 clone (large hook/bobbin) I have oiled it, as it was as dry as the Sahara, but no hard point in the mecanism. The clutch motor is OK (from 1978 !), not as wild as the one I got with the 31K15 and easy to slow down and control, despite it's big pulley.
Even though, I think I will change for a servo because it's so much confortable.
This machine seems to work well but I had a terrible time trying to get a nice even tension. I ended up with a relatively nice stitch (but not as perfect as I want) with almost no tension in the bobin thread, and a lot of tension in the upper thread. Well I thought I had a lot of tension, because when pulling my textile at the end of sewing was really hard.
I then realised that tension was not released when the presser foot was up. Tension discs stayed tightly joined
Searching on this forum I saw Uwe's video about replacing a thread tension release guide on a Tacsew T1563 which is also a clone of LU-563
And I then realized that thi part was missing and some others too. The machine has been modified.
We can here see that thread tension release guide is missing :
The long spring under the arm of the presser foot is missing too and the arm itself was modified, I believe to adapt a pulling system in order to release the presser foot (the system is working) but this arm moves a lot, it's loose, holded only by the big screw on the right.
My questions are :
1. What are the consequences of the missing thread tension release guide and big spring :
- can this explains the difficulty I am encountering to adjust tension, even though I have carefully forced the thread between the two discs to be sure to have tension. I believe my thread path to be OK.
- should I replace both parts and if yes, where can I find them
2. Is a 550w servo motor powerfull enough to run a walking foot machine or do I have to see bigger
I also have watched Uwe's others videos on hook timing, and other settings that must be applied to this kind of machine and I believe these points to be OK (but I can still be wrong, I am a novice)
Sorry if I don't make myself very clear or use approximative words as english is not my mother tongue !
Thanks for reading !