Review on Mgtgbao 5/16”Blue Diamond Finger Bit, 8Mm Diamond Finger Milling Bits For Enlarging And Shaping Or Round Bevel Existing Holes In Porcelain Hard Ceramic Stone Granite Marble Tile by Darin Schaffer

This Mgtgbao 1-inch (25mm) Finger Bit has 5/8 interior threads to be used on a grinder. When using a milling bit, you start the bit on the surface at a 45 degree angle and lift it to the 90 degree position for drilling, finishing or enlarging a hole. The Diamond coating is vacuum brazed onto the surface of the bit for long life. It is best to use this bit slowly at first, and then accelerate the tool more as you breach the surface and straighten up to 90 degrees. The bit can be used dry on most materials, but for granite and other similarly hard stones, you must use water. I personally use water for every job to extend the life of the bit. This tool is great for making a hole for pipes, soap dispensers, electric lines and other things you need to pass through hard stone or glass surfaces. It’s very well made and performed beautifully in my attached demo video on a piece of tile. It went right through it like a knife through warm butter. And I was holding the phone and filming with one hand, so I did the milling with one hand and used very little pressure. An excellent heavy duty tool priced to move!