My way of trueing up DRO rails

[true temper]

I am finally getting around to installing new DRO. It’s a bit different than the old one. I am using the old mounting rails but I need to move them.i was having problems getting them true and square, this is what I came up with. Easy to square and adjust in or out. Did the same thing on other end.

[macona]

They actually dont need to be mounted that precisely in that direction. The head inside the scale float and take up any twist from mounting, some just use teflon slides, better ones have ball bearings that keep the reader in contact with the glass scale. The main thing is getting the scale parallel to the travel, this could introduce some sine error, but in reality there would be more thermal effects on the scale length than sine error that you could ever measure on most DRO systems.

[jmarkwolf]

I've installed several DRO systems on my mills and lathes over the years. I finally came up with these tools for the long rails that save a lot of time. You still need to run an indicator back and forth but only once or so. Then the scales are held snugly in place while drilling and screwing them in. Click on pic for zooming.

[JoeLee]

That's the way to do it. I used a dial when I set my backup spar (basically aluminum angle) I made sure it was parallel with the way surface and parallel with the dovetail. So it I really had to check it both ways.

JL....................