JINGLING Premium Quality 30Pcs 1 2 3 mm Diamond Drill Bits Kit with 1/8" Shank for Dremel Jewelry Making Lapidary Supplies Tools for Gemstone Sea Glass Shells Rocks
Specifications and shapes:
Product Name: Diamond drill bits for stone, Tile drill bits ceramic diamond, drill for jewelry making
Heads Shapes: Cylindrical
Heads Diameter: 1/2/3mm, Solid not Hollow
Shank Diameter: 3mm (close to 1/8")
Suitable for dremel, various carving machine,lapidary equipment, flex shafts with 1/8" chuck
Drill Depth: 8mm(5/16")
Total Length: 45mm(1-3/4")
Quantity: Total 30Pcs, each size 10Pcs (Including 1mm 10Pcs+2mm 10Pcs+3mm 10Pcs)
Grit: 120 (medium)
Premium type diamond coated grit 120, more durable than ordinary diamond drill bit set
Recommended speed: 24000 RPM or more
1 2 3mm diamond tipped drill bit kit is ideal tools for dremel accessories and jewelry drill kit
Suitable for drilling holes in rocks, sea glass,shells, ceramic, jewelry, etc. 
Jewelry drill bits are used to make beads, earrings, pendants
Use with water as a lubricant is better
Keep the hole you're drilling constantly bathed in water or feed water to the drilling spot. If there is not enough water to cool, the diamond at the front of the stone drill bit will quickly wear off because of high temperature.
Light pressure and slow feed rate are beneficial for chip removal, allowing the head of the glass drill bits to continuously grind the material being processed.
Do not press hard during drilling operations to avoid the drill bit being broken or bent. 
Just a friendly reminder: The Shank diameter of grinding bit is 3mm (close to 1/8 inch)
If your chuck of Dremel is 3mm (1/8 inch) or Universal 3-jaw chuck, then the diamond tip drill bit can be installed directly
However, it is NOT suitable for machines with 3/32 inch chuck, such as Electric Nail Drill
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