I have recently gotten into working with leather and upholstery due to the surge in furniture damage from animals as people return to the work place. Initially I purchased a Singer Heavy Duty machine only to find that it is not heavy duty at all. Next I got Nelco N-250-B-3, but found that 92 thread maxed out the tension system, after that I got a Chinese shoe patcher, but found sewing a long straight stitch can be challenging. Then I got a Singer 95-10 only to find that stitch length is a challenge, so I got a Brother LT2-B831-3 which spec wise should meet the stitch length, but can only achieve it on paper, once you start sewing with real material and thread it can not meet the stitch length, so finally I got my hands on a 111W155.
Little by little I am finding more and more issues with the 111W155 that I have been correcting as I go. The thread tension was so tight that it hurt your finger to pull slack to get the material out of the machine. The outer presser foot was rubbing on the inner presser foot. I then followed on of the navy manual to setup the machine, but turns out the needle travel for hook timing was incorrect in the navy manual as is said to use 3/16". I ended up following the UWE video series to get the hook timing set correctly, and then did the Tension Release Slide video as well to find out that the Tension release slide is bent and non functional. The machine seem to be in working order now, but when i started to sew sofa material, I started to get puckering. I have relaxed the top tension to the point that the spring is barely making contact with the tension disk, and have backed off the bobbin tension to match. Now is I slow slow the lock is pulled to the bottom of the material and if I sew faster the lock is pulled to the top of the material. I still get some puckering so I wonder if the presser feet may be part of the issue. The outer presser for tension is set a couple turns from not making contact with the flat spring. I have not made any adjustments to the inner presser foot since I got it and have no idea what is a good setting for the tension on the inner and outer presser feet since I do not yet understand there role in forming of a stitch and moving of material.
Is there any good reference for setting the tension on the thread and feet when working with soft materials?
For reference the 111W155 came with a 264510 feed dog, 240144 throat plate, 240517 and 240518 presser feet.