Mine resembles yours, Dan. The design is quite effective but requires some getting used to.

1: Observe the height adjustment knob in the second photo. Notice the nut in contact with the blue section.

This nut acts as a lock to prevent height adjustment alterations. Tighten it with a wrench. The c-clamp is unnecessary; there’s no need to tighten the allen screw either.

2: Refer to the adjustable plate for different wire thicknesses in the first and second images. Make sure the top of the hole you select on the plate sits just below the V-groove on the wheel for better traction.

3: 12-gauge wires vary. The thickness of the plastic insulation differs across types. Adjust the wheel height based on the specific wire you are stripping.
If the wire veers off to one side or the other of the cutting head, the wheel may be set too low. If the copper core is scored by the cutter, the adjustment is again too low. Ensure that any bends in the wire are eliminated before processing; they must be straight for optimal feeding. Keep these kinks aside as they can be sold as ICW.
Overall, it's a decent machine, but the manufacturer’s manual lacks useful guidance. One must learn through trial and error.
Safety Note: Always wear gloves while handling wire. The insulation contains hazardous substances, which may not currently be widely recognized but could introduce future risks.
While it’s not comparable to asbestos, it's certainly not something you want in your system.
Edited to add: It's an economical choice suitable for occasional usage. The only part you may need to replace regularly is the cutting wheel. If more repairs are necessary, consider replacing the unit entirely as they pay for themselves in a short period.

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