This big slab of stone is the shop's main reference for flatness. It measures 36“L x 36”W x 6“T, and is a grade B plate. This means the maximum deviation between the highest and lowest points is 0.0002”.

Despite being a rock, this is a precision measuring instrument, and requires care in use.

• Any workpieces placed on the plate must be clean and deburred.
• Do not place any abrasives on the surface.
  • The plate is not to be used to flatten or sharpen anything.
• Ensure the plate is clean and dry before use, using a soft cloth and Isopropyl Alcohol.
• Wipe the plate with a bare hand to confirm there's no dirt, dust, or other debris.
• Cover the plate when not in use.