DRO's

Unless you are squirting so much cutting fluid that it and swarf are flying all over the shop, in your eyes, up you nose etc., I think you are worrying unduly with this. If you mount it in the "customary" position up at eye level I don't think you'll have any problem. At least I never have.

You might want to consider mounting it to one of the small, light-duty LCD tilt/swivel mounts that are available inexpensively these days. You can then position it for comfortable viewing wherever you are standing.

As for the scales, simple covers that shield the scale from the direction of flying swarf/fluid are normally sufficient. (This is easier to implement on a mill that the lathe I think). In fact, on my original mill setup, I simply taped a flap of plastic sheet to hang down over it and ran with that for a couple of years. It fell off once or twice and was taped back on but it did the job perfectly well.

I started with capacitive scales and they worked OK for me but sometimes with some dither in the last digit. They are also known to be somewhat noise prone and vary in which side of the supply is grounded - important if you are powering from an external source.

I later bought three 5 um Ditron optical glass scales direct from China (300mm, 200mm and 60mm) for $53 each and they have been wonderful and have first level sealing against swarf/fluid ingress. (There was a $75 shipping charge although they got to me in Canada in 2 days). Some people in the Shumatech Yahoo group are doing bulk purchases to split the shipping and also to get a slight discount on the scales. Ditron also sell readouts for a decent price.

Edited By Sid Herbage on 02/11/2012 15:12:20

What a good idea Sid

You might want to consider mounting it to one of the small, light-duty LCD tilt/swivel mounts that are available inexpensively these days. You can then position it for comfortable viewing wherever you are standing.

This thread has generated a lot of good info and put me on the right road, though I won't be going to 5um on my old Myford. But certainly there is a chorus of approval for the 3 axis dro kit for a mill.

Cant wait to get it fitted as Ive never had this luxury before, when you think you spent half you time measure and checking cuts, like going from 405 bnw to a new lcd hd colour screen, mind blowing

Cheers

Robin

In a way, you've hit the nail on the head. Once they have gone this route, people no longer consider it a luxury.

[ BTW - you seem to have, deliberately or accidentally, added a background colour to your text - in this case grey so it isn't showing against the normal background (but does in the emailed version), If you are experimenting in that direction, please, please reconsider. There's already one person around here doing it (with a sickly yellow that I presume he considers kewl) and I hope it doesn't catch on. Most people set up their browsers with text and background colours that they are comfortable with and don't need others forcing their own preferences.

Sorry - that turned out to be a bit of a rant. ]

The readout system comes complete with a flexible clear cover over it with only a hole for the switch/plugs etc.It also comes with a wall mounting which you can swivel and push away from machine or suit your view of it.

The sliders on the scales have rubber covers and will stop ingress of fluid and dust but in any case are easily opened and cleaned.

The only caveat is I will not be doing anymore wood cutting with my sawbench in there anymore and will find an alternate place to work with it. The only thing you have to do is measure any space you want to fit the scales then look at the specs. and decide which size you need to buy. The drain hole for cutting fluid will get in the way on the Y slide and you may need table stops . The X slide may have a very small depth for fitting and on the system I bought you can get 32mm. 45mm and 63mm depth scales. I made a mistake at first !

Clive

I don't understand that statement Clive. It seems to suggest selecting the scales by the available space to mount them.

What you need to do is check/measure the end-to-end travel of the axis concerned and select a scale with a measurement length slightly larger. Any smaller and you are either restricting the travel of the axis or (more likely) you will wreck the scale by overtravelling it.

Once you've selected the scale you then have the (sometimes thorny) problem of fitting it into the space available.

I'm referring here mostly to a mill but the principle should apply to a lathe as well (although some - eg cross-slide - travel may be a bit "open ended" and you might then want to fit a positive stop. .....just thinking out loud haven't go around to doing the lathe yet).

Sid you also need to consider the depth of the scale if it is to fit into the available space, on the X3 that Clive and I have it would be very difficult to mount a standard sized scale on the Y-axis so you need to use the smaller profile GS-500 scales. This size scale is also better for the X-axis.

As you can see I only ave a few mm below the read head so a bigger scale won't fit unless its is spaced a long way off the machine

Really depends on the mill/lathe and is why Clive says you need to measure more than just the length

J

Edited By JasonB on 02/11/2012 17:48:53

Edited By JasonB on 02/11/2012 17:50:36

You dont need the more expensive KS500 scales for the SX3 the standard size scales are fine. But you can use them if you want to.

I did a bit of a write up here. **LINK**

Althouh the title says X3 I have an SX3. I assume the SX3 and X3 tables are the same. If you have a long table from ARC just select a longer scale.

Hope that helps somebody

Pete

Edited By Doubletop on 02/11/2012 19:38:17

Sid, the 63mm scale will not fit in the space shown on Jasons Pic. Even then the 45mm depth scale is a really tight fit and I may have to mill off 2 or 3mm of that base plate.

The GS-200 series are only 32mm deep and will fit fine and I may yet have to exchange for one of them.

Luckily I have a friend who has a Schaublin Mill and I have access to it so that may be the way I will go as I have to dismount both X and Y slides to mount the X slide anyway.

For any one contemplating fitting these slides buy a small piece of Alu. angle about 5mm thick as the Cast plates and angles supplied are not too good and I had to machine the surfaces as they were not flat and caused the scale to bow when the screws were tightened.

Clive

Its tight but not impossible. You'll see from my pic the scale cover is a couple of mm below the top of the table. And remember the reader is fixed and the scale moves with the table so that small gap between the reader and the Y jib plate isn't an issues as they don't move relative to each other. No machining was necesary.

I've just had a look at Jasons pictures. I requested the D covers which come with a 10mm thick backplate. That, and the size of the larger scales, stands off the whole assembly so the reader now secures on the back face and not the top face of the casting. compare the two photos.

Otherwise pay the extra $20 and get the smaller scales. Neither option is wrong

Pete

Sorry, Clive. When you referred to "size", I assumed you were talking about the length and it seemed strange to select a length based on the room available for mounting.

All clear now.

> I have to dismount both X and Y slides to mount the X slide anyway.

Ouch!

If I understand you guys correctly, the dimension you are talking about is from the top of the scale to the bottom of the read-head. In that case, on my Ditron scales, this is 50mm. (I didn't realise when I bought them that they had a 39 mm version for not much more money. That might have been easier to mount - but I managed).

This is how I mounted the X-axis to my WM14-WM16 (about half way between) lookalike. There's plenty of room in this case but I don't know how this machine compares with the X3:

Since the scale is mounted "upside-down" I installed an extra wiping seal at the top (regular house-door seal). See other pictures. No machine disassembly was involved (although I didn't have the power feed at that time).

The Y-Axis I simply mounted using the front table slot (that normally carries the travel-stops .... I discarded those). For the Z-axis I had to make up a special bracket (relatively complex to maintain stiffness)

The X3 has vertical sides to the base casting and the slides are vertical sided, its just the space below the table for the X scale that is the problem on the X3. Jason has done his and I am awaiting delivery of my scale which should be here on Mon/Tues. Then I can see how it will fit the available space.

clive

I'm out in the workshop now and from Clives comment realise that Jason's pic is the Y axis. Yes it is tight but using the D covers with the back plate and some simple standoffs from 19mm ally I did my Y like this

Pete

Mine has the angled sides to the base but could they just as easily have been vertical for all the difference it would have made (the moving head bracket could have been ever-so-slightly simpler).

I'm likely missing something on X3 from Jason's picture.

er .... red face .... I got my X and Y confused in my message with the pics up there.

You may have missed this bit in my post "so a bigger scale won't fit unless its is spaced a long way off the machine"

I wanted to keep the scales as close as possible to avoid any risk of movement from having several bits of alloy angle lashed together. (not saying yours is a lashup Pete)

The smaller scale on the back of the table does give a decent surface to put a square against or clamp across the table.

Having the scale on the back is why the table needs to come off for drilling access and allows the front stops to be used. Its not card to take off just keep winding teh handle until the screw comes out of the nut and slide it off.

I think with all these installations there is more than one way to skin a cat, you just need to assess what suits you and your machines.

J

Edited By JasonB on 03/11/2012 08:10:46

Oh, absolutely .... and the more examples the better for people coming after.

On my mill, the only thing that limits the cross (Y-axis) travel is the table crashing into the column. Putting the scale on the back of the table would have reduced the cross-travel which was not an option for me. I'd never found the table stops on the front to be particularly useful so their loss was not an issue and mounting the X-axis scale was pretty simple and direct using the slot and existing holes. Bit of a no-brainer in this case.

(Although I later bought a power feed - you can see it in the pics - which uses the front slots for it's limit-stops. I'm running without the stops at the moment but the article in the latest MEW, while not directly applicable, has started me thinking .....)

The most difficult mounting for me was the Z-axis scale which necessitated a two part cantilevered bracket which, as you say is best avoided if practical for reasons of stiffness. It can be done successfully though, if you need to, by machining custom "structural" brackets designed for stiffness rather than simply using what comes to hand. The Z-axis mount took me probably 8 hours to machine (a fast machinist I ain't) but I think is worth it for the flexibility (in locating the scale not in the bracket ) it gives you.

Edited By Sid Herbage on 03/11/2012 14:33:08

To John S,  

Mention was made earlier about scales on a Lathe and the fact that the tool taking a cut took twice the depth of the cut off the dia.

I have just been reading the book of words for the Display unit and it has a section for use on a Lathe, here it says that you set up the work and take a cut to a set dia. (Perhaps 22mm) then at that stage you set Absolute Zero on that scale, then you can use that scale setting to turn to the dia. you require.

There is also a function where you can set it to read Radius or Diameter readings. So it is as I thought, take a cut, reference it and work from there. Whether it is set to radius or Diameter you know from the readout what you are taking off against your final diamter.

Clive

Edited By Clive Hartland on 03/11/2012 20:34:23

Edited By Clive Hartland on 03/11/2012 20:35:08

On my readout the 1/2 button switches between radius and diameter. There is no indication what you are in so I do as Clive suggests and make a trial cut to find out. It will keep your last setting but a case of don’t assume check.

I've also found that the if you have a scale on the saddle and top slide the "integrate Y&Z" function the "ARC" button on mine. sums the two scales on the Y readout so you can move the saddle and top slide and maintain reference along the job. This expects cross slide on X, top slide on Y and saddle on Z. If you want a DRO on the tailstock I'd suggest a means of switching the saddle and tailstock connections to the Z readout