Cheap DRO for Mill

[ChrisHParticipant @chrish]

I am another that has the cheapest DRO system offered by Arc on my mill. I wouldn't want to be without it, but it is fairly basic – realistically for me it just gives a digital easily read position relative to a datum and in either imperial or metric readily switchable; it is what it is, a cheap way of getting a DRO on the mill and one must recognise that, to get more functions and better quality one has to pay a lot more.

It has not been without it's problems. The display threw a loopy very early on which Arc readily replaced FoC no worries. The display also used to switch itself off, a feature that used to manifest itself usually when I switched the 1ph mill motor on or off – that doesn't seem to have happened since I switched to a 3ph motor with a variable frequency controlled inverter. Also the readout bars occasionally 'stick' – you wind the table along but the display doesn't vary but then jumps to the new position, and occasionally an axis zero's itself for no apparent reason. I have lived with it and worked around it as it is what it is, but that does disappoint. Having said that I've happily had the system for very near 4.5 years now and not regretted buying it.

However, I do lust after a more upmarket DRO set-up like that marketed by Machine-DRO or EMS-i, with the small magnetic readout bars and all the desirable functions, but so far have struggled to justify the capex-spend with Senior Management! One day perhaps…..!

Chris

Edited By ChrisH on 24/04/2019 12:05:14

[Nick Taylor 2Participant @nicktaylor2]

I hate to break it to you gentleman, but I would place good money on the MDRO and SINO equipment being made to the same specs and even on the same street as all this cheap Chinese stuff you are warning people off.

I bought a Jingce 2 axis for my Chipmaster at Christmas, cost £125 from banggood. The only problem I have had with it is that it is very susceptible to electrical noise from my VFD, so I’ve had to combine all my machine earths to a common point on a copper stud I made and screwed into a tapped hole already on the lathe bed inside the existing electrical cabinet. Before this the scales would randomly start counting when the motor was either ramping up or down. Since then it has been very reliable.

Last week I did a job for my current employer – some linear bearing mounts for hydraulic test fixtures. All done on the DRO, didn’t look at the dials once I had set the cross slide diameter on the first part. This is mostly because they were metric parts and the machine is imperial. Kept my finishing cuts the same at 0.5mm (0.25mm DOC) and all parts passed inspection on a 0.025mm tolerance on the OD and shoulder length.

[Matt Stevens 1Participant @mattstevens1]

Posted by Nick Taylor 2 on 24/04/2019 15:52:39:

The only problem I have had with it is that it is very susceptible to electrical noise from my VFD, so I’ve

Hi Nick,

I used to work in the VFD Development team at Siemens – they can/do generate alot of noise. You should be able to change the switching frequency which might help, but also make sure you have a screened motor cable (most important) and proper earthing that you already eluded to.

[Matt Stevens 1Participant @mattstevens1]

So….there is a guy thats given a review of the JingCE 2 axis DRO….seems a fair review watching it, and the guy essentially gives it a thumbs up for home use. See what you think…

**LINK**

[Neil LickfoldParticipant @neillickfold44316]

With a DRO, look at what you are requiring from the unit. Some have a much nicer and user friendly interface than others. If it is just to pitch holes and replace the normal dials on a machine tool any dro will do. If you want to cut curves, or put a row of holes on an off square axis, then look for a dro that has the lines of information that will show a radius value or and inclined layout. Some cheap dro that have these sort of features are like this one.

**LINK** You will have to do a search for the tech-3i manual. Anyway one feature I do like about it is the Radius feature for the odd job that does not require the resetting of a rotary table. My kit came with the 5um glass scales and are very happy with it. There are cheaper units, but I have not seen a cheaper one with the data line.

Most will have the reference thingy in them for if the power goes off and the axis is moved while the power is down. This will set back the reference again, assuming you used it to start with.

The one I really liked the best is from Newall DP1200, but that unit and scales is work more than my mill, but is really user friendly, and has a great graphic interface when the tool is approaching the zero point etc. It is what is on the lathe at work.

Neil

[Nick Taylor 2Participant @nicktaylor2]

Posted by Matt Stevens 1 on 24/04/2019 22:23:43:

So….there is a guy thats given a review of the JingCE 2 axis DRO….seems a fair review watching it, and the guy essentially gives it a thumbs up for home use. See what you think…

**LINK**

Hi Matt,

I do have shielded cable on the motor feed, makes me wonder if I should use shielded for everything including the DRO power cable and the VFD controls. I am running at the lowest carrier frequency that is inaudible as I am using the original 1970s motor and I have noticed current consumption and heat both rise when using the highest carrier. I don't run below 30Hz for this reason.

A few other youtube channels have used this DRO, generally good reviews;

Enots Engineering, fitted to a Boxford and MrPragmaticLee, fitted to a Chinese 11×27 lathe

Lee encounters the same problem I had with the Chipmaster – the saddle is too small for the scales, so I have done a similar thing and fitted my scales outboard of the rear of the saddle. Luckily there is plenty of room behind the Chipmaster so I didn’t need to alter my splash guard.

[Henry BrownParticipant @henrybrown95529]

I've been following this with interest as I am awaiting a new SX4 mill from Axminster and want to add magnetic X & Y scales with a DRO. It seems that the only sellers offering magnetic scales are the main suppliers at present, Machine DRO, ems-i, GTPrecision and similar. The ebay offerings are all glass scales as far as I can see and seem to be a bit of a lottery in what you get but starting at £170 odd they needed to be considered against the £390-£400 offerings by those mentioned above.

Edited to add:  Thanks for all the observations already posted!

Edited By Henry Brown on 25/04/2019 09:10:28

[RobCoxParticipant @robcox]

I fitted a 3 axis DRO from Machine-DRO to an SX2 mill a few years ago. I bought magnetic scales as they were more suited to the size of machine. When I sold the mill (minus the DRO!) I moved the DRO onto my Elliott mill. I only needed to buy new magnetic scales – which are comparatively cheap – to adapt the different travel lengths. The read heads are the expensive bits and they just needed new custom mounting brackets to suit.

[WearyParticipant @weary]

Re: Magnetic Tape Encoder Strip.

Does anyone have any experience of using self-adhesive magnetic tape encoder strip? I ask as it seems the least bulky option as regards magnetic encoders/readers, and some of the encoder/reader combinations seem relatively bulky, especially direct from China.

Obvious main interest is how the self adhesive strip might stand-up to the rigours of a somewhat brutal home-workshop.

Regards,

Phil

Edited By Weary on 25/04/2019 09:44:35

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