Folks,
I have a 4x8 CNC router that was used in a previous life to do work in plastics. Since rescuing it from an industrial surplus, I've managed to use if for quite a few things, but I'm always having to screw around when it comes to work holding. The machine has a 5/8" thick plate steel top. It originally used retractable pneumatic pins to align and hold work in X/Y and dual rollers to hold work down. The pins (both fixed and moving) protrude through the table and are set up for 39x80 stock and the rollers (along with a few other parts) were missing when I originally got the machine.
I cleaned up the table and have been using vacuum pucks for most workholding, but the existing table plate is nowhere near flat. It can vary by more than .050 over the entire surface. My thought was to clad it with another material that can be machined flat. Since I have a 10HP becker rotary vane (dry) vacuum pump that I want to integrate for hold down, the question I am now facing is what material to use on top of the steel. Ideally, I would like to bolt it down on a 6 or 8 inch grid with countersunk socket head screws and then machine the topside with a vacuum grid and 6 or 8 ports the will hook up to vacuum plumbing underneath the machine and have zone valves, just like almost every other machine out there.
I was thinking that .875 thick garolite (black phenolic, grade XX or CE) would make a good choice for a durable cladding material that I can machine the vacuum table grid into and face off to be dead flat. Any recommendations on whether this would be a good choice? I used it for all of my vacuum pucks and they have held up pretty well so far.
I have a 4x8 CNC router that was used in a previous life to do work in plastics. Since rescuing it from an industrial surplus, I've managed to use if for quite a few things, but I'm always having to screw around when it comes to work holding. The machine has a 5/8" thick plate steel top. It originally used retractable pneumatic pins to align and hold work in X/Y and dual rollers to hold work down. The pins (both fixed and moving) protrude through the table and are set up for 39x80 stock and the rollers (along with a few other parts) were missing when I originally got the machine.
I cleaned up the table and have been using vacuum pucks for most workholding, but the existing table plate is nowhere near flat. It can vary by more than .050 over the entire surface. My thought was to clad it with another material that can be machined flat. Since I have a 10HP becker rotary vane (dry) vacuum pump that I want to integrate for hold down, the question I am now facing is what material to use on top of the steel. Ideally, I would like to bolt it down on a 6 or 8 inch grid with countersunk socket head screws and then machine the topside with a vacuum grid and 6 or 8 ports the will hook up to vacuum plumbing underneath the machine and have zone valves, just like almost every other machine out there.
I was thinking that .875 thick garolite (black phenolic, grade XX or CE) would make a good choice for a durable cladding material that I can machine the vacuum table grid into and face off to be dead flat. Any recommendations on whether this would be a good choice? I used it for all of my vacuum pucks and they have held up pretty well so far.