I have a two 3" granite surface plates that I use for a turntable stand. I recently found a new bearing that is taller than the stock one and would like to bore a 2 inch diameter hole in the lower plate. The original cut-outs were done by a water-jet machine but transporting the plate is difficult and I'm not sure if they can do it without a CAD drawing anyway. Any opinions as to the feasibility of a DIY solution? The hole doesn't have to be perfect. It is just for clearance. The hole would go in the second picture basically in the center there the heaters meet.
I'd suggest diamond core bit and suitable drill.
They can be hired (including the bit) though a 50-is mm bit is not too expensive if you have a suitable drill.
You could test drill with a normal masonry bit then chain drill but it would look unsightly.
They can be hired (including the bit) though a 50-is mm bit is not too expensive if you have a suitable drill.
You could test drill with a normal masonry bit then chain drill but it would look unsightly.
I have the typical hand drill type stuff. Wondering if it will cut through 76mm of surface plate. Don't want to chain drill it even though it won't be visible.
Water jet.
Drill will be tedious.
There are kitchen counter makers who make these out of solid stone, with CNC machines. Mass production, low cost.
Check out their prices, then decide.
Drill will be tedious.
There are kitchen counter makers who make these out of solid stone, with CNC machines. Mass production, low cost.
Check out their prices, then decide.
Granite has about the lowest thermal coefficient of expansion among common materials.
Much less than cast iron, for example.
Negligible difference between 0 and 40 C.
Look it up.
So drop the heater idea, waste of time.
Much less than cast iron, for example.
Negligible difference between 0 and 40 C.
Look it up.
So drop the heater idea, waste of time.
Getting the base back up the stairwell, into a vehicle and to a water-jet provider will be difficult hence the question.
The heater is to warm the motor and bearing - shortens the speed stability problems when in a cold basement. Works fine really. Been working for a number of years.
The heater is to warm the motor and bearing - shortens the speed stability problems when in a cold basement. Works fine really. Been working for a number of years.
You seriously want to drill granite, in the basement? Pretty sure you will need a lot of water to cool a drill.
jeff
jeff
Just ignore them. It always amazes me to see, although being a DIY-forum, how people always line up
to shoot down things, they never have seen or experienced before. Happens in almost every thread, and often by
the same "very helpful" people.
Congrats to you for finding a way to keep the old "thick oil bearing" at a decent, constant temperature, no matter
the surroundings. 👍 👍 👍
Just needed to get this of my chest. Unfortunately, I have no experience in drilling in stone materials, so won´t try.
Good luck with the project 😉
to shoot down things, they never have seen or experienced before. Happens in almost every thread, and often by
the same "very helpful" people.
Congrats to you for finding a way to keep the old "thick oil bearing" at a decent, constant temperature, no matter
the surroundings. 👍 👍 👍
Just needed to get this of my chest. Unfortunately, I have no experience in drilling in stone materials, so won´t try.
Good luck with the project 😉
Rent a core drill....... but I gotta warn you, if you can't move a surface plate, you're not going to like moving a core drill. Having said that have several 18" x 24" x 3" granite surface plates for equipment stands. Once strapped to a hand truck they go up and down stairs pretty easily. As for example this one under a sub-woofer
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There are core drill bits that claim to work dry.
I've sent an inquiry off to them.
I only need to do this once.
That's why I'm asking. I'm thinking 3" of granite is pretty resistant to breakage but....
That is why there are dollys! OSHA allows 70 pounds per person. Personally I am getting older and find 50 pounds a bit more comfortable.
Worst case ask a friend for help.
Machining wet is not all that tough. You need a recovery pan that the granite will sit in, an overflow tank that a suds pump sits in. and some water born surfactant., maybe a cheese-cloth strainer and some way to manage the flow. The OEM coolant delivery on my lathe, milling machine and surface grinders are a little more elegant in execution, but certainly not more complex.
Cutting fluid systems are as much about swarf control and air quality management as cooling
Breakage happens when you lose control of expected tool or work kinematics. Which is to say: A hand drill is potentially problematic.
Cutting fluid systems are as much about swarf control and air quality management as cooling
Breakage happens when you lose control of expected tool or work kinematics. Which is to say: A hand drill is potentially problematic.
I suspect with the existing cutouts there may be non-uniform stresses in the piece, just waiting to explode!
