DRO on a Mill

I have a round column mill/drill with a 'DRO' on each axis, but basically, and they are basic in DRO terms, they are just digital scales. I was looking to ugrade the DRO set-up to one of the more comprehensive DRO systems with magnetic scales that give you all sorts of options on the display. Initially I was looking for a 3 axis DRO but now I wonder......

The problem is with the Z axis, On a round column mill attaching a magnetic (or optical for that matter) scale is not easy, bits have to be made and attached somehow, in fact I think I am right is saying Warco (who supplied the mill) says it can't be done, which I suppose would be a red rag to some folk to prove them wrong and until very recently that include me. But looking into the way the up-market DRO's work, it seems that maybe a 2 axis DRO system is the way to go as one can make the DRO think a Z axis input has been fed into it.

Which made me wonder just how much a Z axis input is actually used in machining most run of the mill (excuse the pun) stuff, or put it another way, how often does one do inclined milling and need a Z axis input. Mostly, for what I have done in the past, the Z axis just sets the depth to which I am going to mill to, or drill to, end of.

So my question is, am I missing something that would make it absolutely necessary to have a 3 axis linked up DRO, or would a 2 axis DRO with a digital scale on the Z axis work just as well? What have other folk found, what do other folk do?

Chris

First thought is "is there a quill?". You may not need to use the DRO for more than the travel of a quill, and this can be done with a collar around the quill and a vertical scale.

Incidentally, if your present system is the type with remote displays, you might be able to use them with Touch DRO which uses an android tablet (I use a Kindle Fire) as a display.

Brian

Your 2 axis DRO plus digital on the Z axis is the best compromise for a drill mill, go for it.

That's what I went for and find the setup quite adequate.

John

Brian, the Z travel is all on the quill and what you dscribe is how I arranged it.

Old Mart and John, you are confirming my thinking!

Chris

I bought three axis unit and assembled X/Y into dro. Left Z as "future expansion" I have plan, but I am not yet in agreement with my self on execution.

My warco mill/drill has pretty basic depth stop I upgraded it loosely like in this video:

https://youtu.be/4eY_8wCVGMg

And mounted el-chepo scale to quil:

https://madmodder.net/index.php/topic,12858.0.html

Pekka

I find I use the Z axis 1 micron magnetic scale a lot on my mill, it is so handy in many ways. If you can fit one it is well worth it. A scale on the quill is also very handy but is no replacement for a Z axis scale.

Doug

OP has a round column mill.

I find a basic digital scale on the quill indispensable for drilling. Some folks are keen to say it’s not very accurate but It’s been more than good enough for me.

I have an RF-45 mill/drill and have the Z-scale on the quill which is much more accurate in controlling the height of the cutter. The mill head is normally locked in position when machining to make it more rigid while machining. Even more important on a round column mill because the head could rotate on the column. Much easier on my mill to adjust cutter height with the quill than with the column because it has a geared micro adjusting knob which can raise/lower the quill by a thou or 2.

Paul

Same for me; I've not had any probs with mine on my WM16. I have also fitted X & Y axis readouts to it so in effect, 3 dro's. see my album 'DRO'

George.

My original mill, a Sieg SX3 had a digital scale fitted to the quill but the RF-45 (clone) did not.

My Easson digital readout has lots of features. Bolt pattern positions, PCD, inclines, different memories and can cut a curved edge by moving the cutter to the X and Y co-ordinates shown on the display. With the addition of a scale on the Z-axis, this can also be done vertically.

The Z-scale is bery useful for not only drilling holes but for accurately milling to a specific depth.

Paul.

hi brian g

i would like to know how you managed to use a kindle fire for your dro system as i was unable to use my kindle fire for my dro

regards geoff

I fitted a 3-axis DRO to my Centec - the Z-axis was for the knee. I find the Z-axis scale very useful, but added a simple auxiliary scale for the quill which gets used for drilling.

When I was considering fitting DRO I originally budgeted for a 2 axis system, but was advised by more knowledgable members of the club to bite the bullet and pay the extra for the 3rd axis.I never regretted paying the extra.

I have an Emco FB-2 (Round column mill) which I fit a 3 axis DRO which I bought from Allendale. Works a charm and I use the z-axis a lot. I am not sure I understand why this is an issue? If you google “FB-2 dro” there are several iterations of the z-axis.

What keeps the head from rotating on the round column. I know some mills have a guide/key but will still allow a slight mis-alignment when raised.

Paul.

As I see it, if there is a key there will be ‘backlash’ of some description. The best one can do is tighten the securing device with the column positioned such that any cutting forces are immediately resisted by the key.

I think most of these machines likely suffer from rigidity problems, so this is only the best option - but not a perfect solution because the machines are a (poor) mechanical compromise at manufacture/build.