What DRO to get?

Hi,

I have an Ajax milling machine for the last couple of years. I think its a ajt1. It looks the same as the one in the link **LINK**.

I have tried looking up getting a DRO system for it but there is so much information on the net and it's overload at this stage. It would be for the X & Y axis with the option of a Z axis maybe down the line. I don't need a top of the range bells and whistle one but one of decent quality. I make a lot of bushes and brackets etc for motorbikes but I have some model kits that I would like to get to sometime so I don't know if that influences my choice.

I have looked up the forum and can't find any definitive guide (Sorry if there is). But if anyone could point me in the right direction or give me some links I'd appreciate it.

I have emailed **LINK** for some information but never got any response.

Thanks,

Aidan.

Aidan,

I installed a Sino system from Machine-DRO to my Emco FB2 a few years ago. The installation was fairly painless, the instructions were helpful, and the company themselves were helpful when I needed to ahve something changed. Sorry you didn't get a reply from them, maybe something went awry or it was holiday period. I do recall having a chat with the Machine-DRO chaps at an exhibition, and they did seem quite helpful; maybe you could try that.

A year or so after these pictures I also fitted a Z-axis scale; this involved slightly more fiddling around with brackets to get both ends of the scale fixed to the column, but it was fiddling rather than difficult. The installation has worked flawlessly for me since installation. Here are some pictures:

I know there have been some articles in MEW about installing scales to various machines, but more often lathes rather than mills; I suspect this is because installation to milling tables is usually quite straightforward. What I would say is that the fitting of the DRO transformed the precision I could routinely (i.e. without very tedious exceptional measures) achieve in milling and drilling, and I would not be without it. I would say, don't let yourself be seduced by cut-price bodges with digital calipers or scales, go for the quality stuff; the pleasure is enjoyed long after the pain of paying is forgotten.

David

Edited By David Littlewood on 27/08/2012 13:06:34

You are unlikely to find a system straight off the shelf for your mill. You will have to follow the guides on the suppliers sites to determine what lengths of scales you will need. Have a look at this suppliers page from the US, it shows a lot of installations which should give you an idea of how to fit the scales to your machine.

I did the same as David and bought a 3 axis display but just scales for the X&Y and then about 6 months later added the Z axis and found Machien DRO very helpful. Also get the covers for the scales as they make fitting a lot easier.

J

Edited By JasonB on 27/08/2012 13:15:38

First off you need a 3 axis readout. The cheapest of sufficient build are from Allendale about £130, i have two. http://www.machine-dro.co.uk/budget-3-axis-mill-dro-console.html

Y axis simple get a C type glass scale and cover.

X axis is a different matter, mount on from and loose all forms of using stops and it sticking out from bed. Mount on rear and loose travel plus risk swarf pushing reader and or getting inside the glass scale. Easy to clean. Other way is pay extra for the magnetic scales, they are just as accurate i have proven it some where regardless of the spec. Magnetic are ultra slim about 1/4" and could be dropped down the X axis below bed locks and or T slots, or even mounted on rear.

Z axis at a later date the easiest due to shallow head heigth and objects in the way is definately a magnetic. You only need the max travel plus think its 47mm, a lot less than glass scales then add in the covers loosing another 2" plus.

For magnetic you would need a suitable length of this and then cut down, easy. http://www.machine-dro.co.uk/two-part-magnetic-tape-support-profile-1000mm-length.html One of these http://www.machine-dro.co.uk/magnetic-linear-encoder-reading-head-5-micron-resolution.html Though they now do a 1 micron. Multiple one piece length of this, cut to size required and not limited to any excess. http://www.machine-dro.co.uk/high-accuracy-magnetic-linear-tape.html

Seen plenty of disasters even by pro installers mainly due to them having to do an install jobby as quick as possible, what you dont want is for the items to get in the way.

Hi Aidan I use a Machine Dro on my Harrison lathe , very easy to fit and use

On my Mill I have a Mitutoyo 2axis and on the quill I fitted a vertical vernier from Machine Dro

I never got round to doing the knee axis

Re contacting them I found I got a better resonse by phone

Paul

Hi Aiden,

I recently used the magnetic scales from Machine DRO along with their budget 3 axis read head on my Lathe. Using the 1 piece aluminium mounting hardware, fitting was relatively simple.

I also have an Ajax mill, although it's the big brother to yours (AJT4). This has glass scales on the X and Y.

The X axis is mounted on the back of the table so as to retain the limit stops, Y axis scale is mounted in the right side of the Knee.

I have also mounted a simple chinese scale on the Quill which is useful when drilling.

The magnetic scales are easy to keep clean and are pretty much unaffected by liquids.

CB

I have just fitted a dro from Machine DRO to my Tom Senior mill. Magnetic Scale because of the slim profile. It could not have gone easier. Would recomend the display unit with all the bells and whistles as it is good for setting out etc.

Hi Aidan

Have you tried Goodwin Technology www.GTprecision.co.uk

Ask for Darren phone 0151 608 8666 I can highly recomend him for competatively priced DRO equipment and also used machinery.

I am speaking only as a very highly satisfied customer.

Good luck

Dave C

I am in the process of fitting a Machine DRO magnetic scale to the cross slide of my Myford Speed 10 lathe. I chose the magnetic scale for two reasons, firstly because I could fit the magnetic strip under the slide (only 1.5mm space needed) and secondly because the reading head is very compact and will fit out of the way behind the slide.

By using a 6 pole changeover switch I will be able to use the display fitted to my mill and simply switch between the Z axis of the mill and the lathe cross slide thus saving buying a second display unit. I have a 1 micron resolution magnetic scale on the Z axis of the mill along with 5 micron glass units on the X and Y scales and find this combination very nice indeed. I nearly bought the 5 micron magnetic option for the mill because it was cheaper, but I find the 1 micron unit superb and worth the extra expence. The lathe will also use a 1 micron unit and I hope to have it up and running shortly.

Doug

Good find that John, better than Allendale readouts though the scales look exactly like Sino.

May be worth a call for those that want magnetic just to buy only that from Allendale. Readout and and glass scale from that link Xaio.

Douglas you might have a problem if you do that though havent tried the magnetic strip in anger without the two piece housing and in turn silicon seal it in. Thinking debris one side is soft the reverse side, the sticky side is the reader side. Mines still going strong on tailstock and cross slide two years on.

[IMG]http://i1140.photobucket.com/albums/n563/Jonhareng/Harrison%20M300/M300DROCABLING004.jpg[/IMG]

[IMG]http://i1140.photobucket.com/albums/n563/Jonhareng/Harrison%20M300/M300DROCABLING005.jpg[/IMG]

[IMG]http://i1140.photobucket.com/albums/n563/Jonhareng/Harrison%20M300/M300DROCABLING006.jpg[/IMG]

I have used a thin metal cover over the magnetic strip Jon as I was concerned about metal swarf causing a problem since the surface of the strip has about the same magnetic attraction as a fridge door seal. the strip being under the slide should provide a fair ammount of protection but I might have to think about shielding the scale further if its going to be a problem.

Doug

Thanks to everybody that has taken the time to respond to me. I have gotton some really good information and it has really simplified what choices I should make as I had information overload before by reading all the different websites.

I will hopefully pick out a system and run it by you all before I make a final decision in the next week.

Thanks again,

Aidan.

Should be fine Douglas. Quite expense for short lengths but become more economical on long runs such as X axis mills and lathes.

To my knowledge only Allendale do the magnetic jobbies. Did see a demo ML7 with glass scales at a show some years back, enough to turn anyone off making the machine unusable.

Any install should be rigid, most skimp on the quill as hard to do properly.

I have the Allendale Sino units on my SX3 mill and Newall units on my Boxford Lathe. Newall are probably better quality but twice the price. IMHO the Allendale units are better value than any old Sino ones for one simple reason...The Manual. The Sino one is absolutely incomprehensible but the Allendale one for the same units is really good. They rewrote them themselves and it was certainly worth the effort. I don't use most of the features on my upmarket reader head but no doubt will do so as I get more experienced. I have X,Y and Z axis features and the machine has a short range DRO on the Quill. The Z scale is really helpful and probably the one I read the most, tho' currently cutting dovetails for a boring head a la Harold Hall and the Y axis is great for not taking too big a cut a lunching the dovetail cutter. So in conclusion you gets what you pays for and as David Littlewood says the pleasure of quality lasts far longer than the sting of the price

Andries

I purchased Sino units off Ebay shipped from Hong Kong and would recomend them, apart from the manual. I found the SINPO manual, is written in English and surprise surprise its virtually the same as the SINO manual, has the same diagrams, display wording and control sequences, Only the keyboard/front panel layout is different. They must be the same electronics in the control unit. So if you are struggling with the SINO manual serch for a copy of the SINPO manual, it's marginally better.

Pete

Have any of the installers/users of the magnetic scales from M-DRO checked them for accuracy after installation ?

I finally managed to finish the installation of a 2 axis system (basic lathe console + 2 off 5 micron resolution magnetic read heads) onto a Swiss made tool presetter at work yesterday. The installation was required after the Trimos capacitive readouts died & the UK agent for the presetter quoted £2500 - £3000 (+Vat) for the original equipment units - the M-DRO setup came in at around £420 inc. Vat delivered IIRC.

Anyway, after getting it all installed, the first thing I noticed was that the diameter readout was not reading tool diameters correctly. The spindle has an accurately ground (127.00mm) outside diameter that is used to datum the X readout. When I put a tool in the spindle & checked various diameters, the readout did not show the correct dimensions - around 0.08 out on a 24mm nominal feature. Checking the vertical travel to Inspection grade slips showed a smaller error - around 0.015 at 200mm. The console has a length compensation feature - setting compensation values for both axes has got both reading correctly - though the compensation values differed widely (-600 on X, +75 on Z). As the magnetic strip was supplied as 1 piece & I cut it to suit both axes, I see 2 possibilities for the differences - the read heads require individual adjustments, or the magnetic characteristics of the slide affect the strip. As the X axis on the presetter is machined from stainless steel & the Z axis is an aluminium extrusion with inset stainless steel guides, I suspect the latter.

The magnetic systems do command a hefty premium, though - I went through the exercise of pricing a 3 axis system to suit my FB2 clone, with travels (from memory) of X 400, Y 150 & Z 400 :

Arc Eurotrade capacitive scales with 3 axis console £210

The Arc 3 axis display is much more basic than the Sino unit, but the system was included to show that a very basic 3 axis system can be installed relatively inexpensively. I discounted Arc's cheaper option of scales with remote readouts directly attached, as the accuracy quoted seems poor to me for machining metal & not directly comparable with the other systems below.

M-DRO 3 axis "economy" mill console with 3 x "Full size" scales £480

As above with 3 x "Slim" scales £545

As above with 3 x 5 micron magnetic heads, 1200mm of tape & 1500mm mounting spar £700

As above but with 1 micron magnetic heads instead of 5 micron £790

Prices "rounded up", including Vat, excluding delivery.

The price in the link from Bogstandard2 looks rather more attractive !

Regards,

Nigel B.

I checked Johns link to ebay and thats the guy I got my DRO's from. Helpful and prompt

Pete

Aidan, I would like to fit a 3 axis DRO kit to my Centec mill, and have been looking at Chinese offers on eBay. I selected a couple, trading as 'industry.factory' and 'cncpart2018' and asked Gary Wooding to cast his expert eye over the specifications, which he very kindly did. At the end of the exercise Gary said he would be prepared to take a punt on either of them, which satisfied me. If it's good enough for Gary .... etc. Both of the systems use glass scales, and I selected movements of x-axis 250mm, y-axis 150mm, z-axis 50mm as the basis for quotations, which came in at £140 - £150, complete with swivelling arm support for the DRO unit. Shipping to me in Scotland via Fedex or similar would cost another £40 - £50. So far, so very good. A complication and added cost is VAT at 20% on combined price + shipping charge, so another £40, and the possibility of import duty, something I am still investigating. HM Customs tell me that if the unit price is £135 or less then as a private individual no duty would be payable. Maybe something could be done there by splitting the purchase; buying the z-axis later might do it. If you want a good example of red tape look at the regulations determining the duty payable on a pair of trousers, an example given on the Customs website, mindblowing.

My exercise is not yet complete, but one conclusion is that very respectable gear is available at relatively low cost, and though importing it adds expense it might still be an economic proposition.

If any readers have actually done this, and there must be some, I'm sure, it would be really good and very helpful to such as Aidan and myself to hear of their experiences. How about it ?

Hi Ken,

Yes, I went down the direct from China route as the cheapest option. I bought a Sinpo 2 axis for my Chester Eagle 25 mill as Sinpo seem to get good reviews.. My logic was that most of the ones that you can buy in the UK come from China anyway.

I paid £264 which included the postage and had to pay another £20 VAT when it went through customs. Took a couple of weeks to arrive but have been very pleased with it. Best thing that I have ever bought. The DRO and fitting a VFD drive to get rid of the tedious belt changing have made the mill a pleasure to use..

It's been fitted for nearly a year now and is in constant use with no problems. There were a couple of plastic end caps for the covers missing but that was no big deal.

John

Edited By John Baguley on 17/04/2019 23:42:58

I reckon your thinking is flawed. The z axis on mine is certainly not 50mm. A couple hundred, more like.

I have a separate reader for the quill, but the main dro is on the table x, y and z axes. I avoid extending the quill for milling, so it only gets used for drilling, normally.

A dro on the z axis certainly needs to be on the table lift when used in horizontal format!