Cross slide DRO

[David]

Ok I'll admit it. Having the DRO scale under the cross slide is an appealing idea.
Here are a couple of shots of the cross slide.
I am slightly concerned that there isn't enough room for the read head beside the lead screw.
There's barely 11mm on each side.

But the lead screw seems overly long.
This shot is where the tool post sits when the lead screw is fully engaged in the nut but the screw is not past the end of the nut.
Seems to me that I could loose an inch or so off the lead screw and be still fine for travel.


At full retract I only need to add about an inch of extension to support the scale.

 

[PaulL]

How much gap do you have between the lead screw and the side of the trench? The heads are basically 10mm thick. I suspect you could cut into them a fair bit as well to make space for the screw if you had to.

 

[David]

How much gap do you have between the lead screw and the side of the trench? The heads are basically 10mm thick. I suspect you could cut into them a fair bit as well to make space for the screw if you had to.

There's about 11.x mm gap on the right and about the same on the left.
I just ordered the same read head the I had on the mill as it's only 10mm thick.

 

[PaulL]

There's about 11.x mm gap on the right and about the same on the left.
I just ordered the same read head the I had on the mill as it's only 10mm thick.

So it should fit and the only question is how to secure it.
Do you have the meat under your cross slide to make a channel to fit the tape?

 

[David]

So it should fit and the only question is how to secure it.
Do you have the meat under your cross slide to make a channel to fit the tape?

Loads of thickness there. But the underside is milled smooth so I may be able to just lay the tape down on the milled surface.
I'm just thinking though assembly.
I could put the cross slide on and bring it all the way forward and loosen the mount for the handwheel so it can come forward enough to reveal the space for the read head. Affix the read head using maybe epoxy or my 'till death do us part' 3M double sided trim tape which is what I used on the mill mounts.

 

[slow-poke]

What about the leadscrew nut?

Mine takes up almost the entire width of the slot?

 

[ChazzC]

That’s an intriguing concept, David: I’m watching!!

 

[David]

What about the leadscrew nut?

Mine takes up almost the entire width.

It's quite narrow, maybe 6mm wider than the lead screw?

 

[David]

That’s an intriguing concept, David: I’m watching!!

I'm definitely not the originator of this idea!

 

[Susquatch]

So it should fit and the only question is how to secure it.
Do you have the meat under your cross slide to make a channel to fit the tape?

This is what I'm doing @David. There is almost enough room as is. But I'm going to mill it a wee bit to make sure it fits.

Regarding the read head, I figured I would add an extension to the cross-slide and continue the tape on the extension. That way the head could go behind the cross-slide.

No travel is lost that way.

 

[David]

This is what I'm doing @David. There is almost enough room as is. But I'm going to mill it a wee bit to make sure it fits.

Regarding the read head, I figured I would add an extension to the cross-slide and continue the tape on the extension. That way the head could go behind the cross-slide.

No travel is lost that way.

I like that idea.
I need to figure out how to mount the read head.

 

[Susquatch]

I need to figure out how to mount the read head.

Since the tape moves with the cross-slide, a simple bracket on the back of the saddle should work great.

 

[PaulL]

Since the tape moves with the cross-slide, a simple bracket on the back of the saddle should work great.

That's where I put mine, with a slide extension to hold the tape for the offset induced by the read head position.

 

[David]

Something like this:

 

[PaulL]

Something like this:
View attachment 64406

Just beware - the extension might run into whatever rear shield/chipcatcher you have at the rear.

 

[David]

Just beware - the extension might run into whatever rear shield/chipcatcher you have at the rear.

Fortunately I have the low-budget version which doesn't have a backsplash. Though I might bend one up because I hate not having one.
In truth, I think the extension only need to be about two inches long. I definitely will have that much clearance between whatever backsplash I cobble together.

 

[PaulL]

Fortunately I have the low-budget version which doesn't have a backsplash. Though I might bend one up because I hate not having one.
In truth, I think the extension only need to be about two inches long. I definitely will have that much clearance between whatever backsplash I cobble together.

I found I needed nearly 6" of extension to cover the travel all the way to the front. Easy to measure, it's just the amount of exposed carriage when the cross slide is all the way to the front.