M-Style Bobbin Chinese Patcher Mod

[GerryR]

I've had a little more time on my hands than usual and decided to mod a Chinese Patcher to handle M-style bobbins to get the added thread capacity.  One of the goals was/is "no modifications to the existing machine" so I can get back to the original patcher just by swapping parts.  Well, I got everything done "except" I need to either make a different swapable hand / cam wheel or make a different needle bar connection to get the additional needle down stroke, about 0.3".  The cam for the bobbin rotation works as is, as the angles of motion are proportional.  I don't know if in the end I will get it all working, but at least I can easily put it back to original.  I think these patchers get a bad wrap, but mine has worked flawlessly.  It's definitely a educational project.  Comments and suggestions are welcomed.

[chuck123wapati]

I'm wishing you all the best and can't wait to see the outcome. I love mine too a little cleanup and a few tweaks and they run like a clock.

[GerryR]

Well, because I didn't have an easy way to make a new hand / cam wheel to get the added needle stroke that I needed, a machine mod was going to be needed.  I had a second machine and chose to modify it to be sure the mods would work before messing with my good machine.   To get the added needle stroke, I moved the pivot point of the arm by 0.75 inches toward the hand wheel.  I had to machine the frame in order to relocate the pivot point, but it worked out pretty well.  I have one small issue that I will address Monday and that will finish it.  It is no longer a true "patcher" but after running it for awhile with different threads I will swap the parts over to my good machine which is motorized.  Here's a few pictures of what I ended up with.