Skiving Machine, Bell Knife, (Techsew SK-4) ID:184

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Industrial leather skiving machine top front view
Type Leather Skiving Machine
Make/Model Techsew SK-4
Serial number tbd
Original owner Protospace
Loan status Owned
Arrival date June 2024
Location Soft goods
Functional status Operational
Usage permissions Trained users only
Certification Skiving machine training
Wiki-ID 184
Label 1.0" 1.5" 2.0"


Manufacturer claims:

  • Skives light and medium leather up to 8oz
  • Up to 2" adjustable skiving width
  • Integrated blade sharpener
  • Space saving table - only 33.5" wide
  • Variable speed 550W 1200 RPM servo motor

Caution: Machine with table is in excess of 200lb. Team lift when moving to protect yourself and the machine.


  1. Always check all settings on the machine before each use - assume someone adjusted something.
  2. Test on samples of similar material before working on important pieces
  3. This machine uses a fast moving razor sharp blade. Do not put your flesh where the leather goes or all your blood will fall out.
  4. This machine's servo drive retains a charge after powering off. Operate the pedal after turning off the power switch (the blade will spin) until charge is drained before removing any covers or performing any maintenance.


Video Guide


Inspect, lubricate, clean, adjust/change accessories


  1. Adjust depth stop to desired skiving width.
  2. Ensure drive wheel preload spring is hooked to drive wheel carriage.
    1. Use more tension for thicker/harder material, less tension for softer or thinner material.
  3. Adjust drive wheel as equidistant as possible to bell knife edge without touching. Drive wheel can be raised/lowered, and angled fore/aft until equal gap exists.
  4. Lower presser foot lever, ensuring foot does not contact drive wheel.
  5. Raise presser height with adjustment wheel to make enough room for leather thickness.
  6. Power on machine with foot clear of pedal and hands clear of all moving parts.
  7. Operate foot pedal until blade/drive wheel moves slowly - Inspect/listen for any maladjustment:
    1. Any grinding/metal-metal contact indicates maladjustment - Stop Immediately.
    2. Check drive wheel clearance/presser foot height for interference. Ensure sharpening stone is disengaged and retracted
    3. If interference was with blade edge, sharpen blade.
  8. Keep hands clear of blade intake area at all times.
  9. Insert leather between foot and drive wheel, butted up against depth stop.
  10. Adjust presser height while running at low speed until foot barely pushes leather into drive wheel.
  11. Let the machine do the work. If it isn't feeding, readjust instead of pushing the leather.
  12. Keeping hands clear of blade intake area: Guide leather under foot, gradually increasing in speed as comfort level increases.

Sharpening blade

  1. Remove all material
  2. Wear safety glasses and engage safety squints. Keep clear blade cover closed*
    1. On occasion, sharpening stone will need to be dressed for roundness, requiring the cover to be opened. Caution, everything in there is sharp, or pinchy/grabby. See user manual for specifics.
  3. Visually inspect through clear cover that the blue grinding wheel is not touching the bell knife.
  4. Engage sharpening stone drive lever (far right) - pulse motor and visually confirm grinding wheel is spinning and not touching the bell knife.
  5. Run motor at medium-high speed while slowly advancing wheel into knife until they make gentle contact. Less is more.
  6. Once grinder makes contact with bell knife continue grinding for a short time (few seconds) until edge is honed. Do not overheat blade.
  7. Retract grinding wheel (few rotations of adjustment knob).
  8. Disengage sharpening stone drive lever (far right)
  9. Use handheld honing stone to deburr inside of bell knife - run motor at medium speed and use round stone parallel to inside edge of bell to straighten the inside edge.
  10. Close cover
  11. Non-Profit.


  1. Power off motor - depress pedal to drain residual charge.
  2. Raise presser foot lever. Never leave presser foot down while not in use.
  3. If you need to clean the bell knife or drive wheel, disengage drive wheel carriage spring (under clear cover)
  4. Using a brush or chopstick - not metal - and NOT YOUR FLESHY FLESH HANDS - clear remnants from bell knife.
  5. Use compressed air to clear debris from machine and work surface.
  6. Close lid, sweep up, cover machine.


Skived area uneven thickness: Drive wheel angle wrong, adjust to be even along entire length of wheel

Does not skive - just cuts leather - Drive wheel too low, raise drive wheel

Skives poorly/jagged/uneven feeding - Too much/too little pressure foot pressure, or blade dull. Sharpen blade, adjust foot.

Top of leather damaged by presser foot - Presser foot too low, wrong angle. Adjust for less pressure, check angle is equidistant along drive wheel


PDF User Manual (Google Drive)