Proxxon Diamond Drilling & Grinding Bit — 3.2mm Ball, 2-Pack (No. 28234)

A ball-shaped diamond-coated drilling and milling bit for precision work in glass, stone, and granite with Proxxon Micromot rotary tools and drill presses. The diamond coating delivers the hardness needed to drill and mill through hard, brittle materials that conventional bits cannot penetrate. Recommended for use on a drill press at 2,000 RPM with additional coolant to prevent overheating and bit damage. Supplied in a 2-pack.

Specifications:

• Shape: ball
• Diameter: 3.2mm
• Shank diameter: 2.35mm (3/32")
• Coating: diamond
• Quantity: 2 bits per pack
• Recommended speed: 2,000 RPM
• Coolant: required for use

Best suited for drilling and milling in:

• Glass
• Stone (including granite)
• Ceramics and porcelain

Please note: For best results, use on a drill press with coolant at 2,000 RPM. Not recommended for freehand use at high speeds without coolant.

Proxxon No. 28234

Works Well With:

• Bench Drill Press TBM 115 — recommended host tool for controlled speed and coolant drilling
• Professional Rotary Tool IBS/E — compatible Micromot rotary tool for lower-speed applications
• Diamond Bur — Cylinder 5/64" × 13/64" (No. 28240) — diamond bur for grinding and finishing the same hard materials
• Diamond Bur — Sphere 5/64", 2-Pack (No. 28222) — ball-shaped diamond bur for concave surface work
• Diamond Cut-Off Wheel 1-1/2" (No. 28846) — diamond cutting disc for the same hard materials
• Diamond Cut-Off Wheel 3/4" — smaller diamond cutting disc for detail cuts
• Distar Water Guard Kit for Proxxon LWB/A — coolant delivery system; required for safe use of this bit
• Proxxon LHW/A Cordless Long Neck Angle Grinder — broader Proxxon precision tool ecosystem

Further Reading:

• How to Drill Through Tile Without Cracking It
• How to Drill Clean Holes in Porcelain Tile Without Cracking It — Proxxon IBS/A + Distar Rocket
• Engraver vs. Porcelain Tile: How to Cut Holes Without Chipping

Returns can only be accepted for unused product in its original packaging. In addition to the returned item/items, a copy of the original packing slip or invoice is required. If proper paperwork is missing, PROXXON Inc. will not issue a credit. For warranty claims please call 1-877-776-9966. Please see our return and refund policy here.

California Residents Prop 65 Information

WARNING: This product can expose you to chemicals including lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.