Diamond Core Bit Drilling Tips

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Always secure the drill rig with a mechanical anchor, vacuum system, or by using the jack screw. NEVER stand on base and drill without anchoring.

Level the drill rig by use of the base leveling screws, and a small level attached to the column permanently or by a magnetic strip on the level. This procedure will insure a perpendicular hole.

Never let the bit spin in the hole without applied pressure. This will cause the diamonds to round off and the bit segments will heat and glaze over.

Turn on water before starting the drill motor. Otherwise, the water jacket seals heat and becomes brittle, losing water.

When your bit encounters steel (rebar), relax pressure about 1/3 and allow the bit to cut at its own rate. DO NOT PUSH THE BIT. Some operators turn the water down after exiting the steel to sharpen the bit. If you engage in this practice, don't forget to turn the water back up once the bit is sharpened.

When drilling high psi concrete or concrete with very hard aggregate (i.e. river rock, flint rock, etc.) the bit will sometimes glaze over. To open or redress the bit, do one of the following:

• Decrease water about 1/2 for a few minutes and as the bit starts to increase speed, gradually increase water until flow is back to original state.
• Pour masonry sand into the serf, and then follow the above directions.
• Add sandblast media such as "Black Beauty" to the serf and follow above directions.
• Drill bit into cement block, soft vitrified grinding wheel or cinder block. Repeat procedure until the bit is open again.

When finished drilling, turn the water down very low and back the core bit out of the hole with the motor running.