Some background: the machine came to me in a non-working state. two gears were rusted and seized and the hook timing and hook-to-needle gap were both way off. After adjusting both hook timing and gap I've managed to get it to straight stitch now without issue through its full range of stitch lengths, but I may be failing to set the zig zag correctly, because I am seeing collision between the hooks and needles.
There are two places on the machine to set the zig zag width: a 1-10 thumbscrew actuated dial on the body of the machine, and a push-button on the bed that is actuated much like the stitch length button, where the drive wheel is turned to set the width with the button depressed.
I THINK the button on the bed controls the range of the left-right motion of vibrating hook assemblies (remember, there are two as this is a double needle machine) and the dial changes the needles' left-right oscillation. But because the dial runs 0-10 and the numbers on the drive wheel go from 32 - 0, I think i may be setting them out of sync, causing the hook-to-needle collisions. Or maybe I haven't adjusted something else that affects the timing of the zig-zag movements to the hook assemblies.
I've had limited success setting both to a mid-setting, say, 5 on the dial and 16 on the wheel, but I am uncomfortable that this is the right way to approach adjustments, and regardless, when i set the dial to 10 and the wheel to 32, I get collision again. I have a feeling I'm missing steps in the adjustment process.