I have a Mitsubishi DU-105 that I can't find a manual for anywhere.
It has triple feed and looks like a 211 walking foot machine....kinda.
It sews very nicely on 4 - 8 layers of sunbrella, but when trying to sew 2 layers, the bobbin thread just lays along the bottom of the material, not pulled up at all.
Under all conditions, I must run massive top tension to bury the bottom thread, and the bobbing carrier makes a violent movement as the thread pulls free from the bottom needle side of the bobbin carrier( I think this binding makes it act like bobbin tension is too high)
I have the bobbin tension set so low you can pull it with no effort at all.
Anyway, looking at the bobbin carrier/hook it appears the take up lever is taking up too soon, when the hook has pulled the top thread half way around the bobbin carrier, thread is drum tight, and the machine is difficult to turn using the handwheel, the thread then fully slides away from the hook and then slightly hangs on the bobbin carrier and the hook at the tail end of the plate that holds the bobbin carrier in the hook.
I can't find any timing marks and there are no marks on the needle bar.
Wondering about advancing the hook so the thread will be past the tightest point before the takeup lever really pulls hard on it/
Anyone have any suggestions?
Wayne