DIY surface grinder

[Saltfever]

edit . . . The new project is a dedicated high precision CNC surface grinder. The table will move on linear ball slides and be driven by closed loop steppers controlled by my dedicated software. To test certain features prior to cutting metal I cut wood instead and mocked up the table and drive system to test whether the stepper size that I calculated would be capable of throwing the table and mag-chuck about at the usual surface grinding feeds. I used a 20 mm pitch ball screw to get the speed. I'll make the base of this grinder in epoxy/Granite and I have a piece of solid granite of suitable size to make the table from. I'll make a full post on this when it is finished, I will be getting back to it later this coming week.

Wow,that sounds like an exciting new project. Knowing the quality of your posts I'm sure plenty of details will be provided. However, that 20mm lead really raises a question. 20mm seems unusually large, and considering the mass of your system (granite plate & mag chuck), it certainly increases the size of the motor! Care to share some of your thoughts about some trade-offs now?

This seems like a "smallish" sized project and would fit into my space. So I'm very interested in seeing how you accomplish micron-value alignments and the kinematics of the whole thing!

You are winning "the race through life", Tony. Keep that right hand WFO* on the straights! LOL


*Wide-full-open

[tonyfoale]

Wow, that 20mm lead really raises a question. 20mm seems unusually large, and considering the mass of your system (granite plate & mag chuck), it certainly increases the size of the motor! Care to share some of your thoughts about some trade-offs now?
*Wide-full-open

The screw with 20 mm lead works fine under my tests so far but it is not necessarily the final choice to drive the table. Back in 2009 when I was at Segway developing a project for GM we used a motor, pulley and wire to slide the top part over the bottom part. That is an option that I am thinking of using, it would be more tolerant of wayward grinding debris over time.

https://en.wikipedia.org/wiki/General_Motors_EN-V

and video

[Saltfever]

You have an affinity for two wheels!

[tonyfoale]

You have an affinity for two wheels!

Oh, we played with single wheels too.

[albertq]

I have the drive but I am 80 in two days so the energy is draining rapidly. I expect that it will have deserted me within the 20 years that I intend to have left.There are a lot more races to ride yet.

There's too much useful information in your head we need, to even think of slowing down Tony.
I love your attitude to aim for 100. If you ask us kindly then, we may allow you to stop then.