M-DRO help?

Morning all,

Here's hoping someone can help. I've contacted M-DRO (Allendale) but won't get an answer until at least Monday, and I would realy like to press on.

I've had the DRO for a year or two and it's been fine up until now.

The "centre find" function on my MDC700 isn't doing as I understand it should.

Following the user manual, instead of displaying 0.000 as the centre of the part, it displays the centre as what appears to be, half of the distance between the two edge finder centre locations. I hope that makes sense?

I was wondering if I need to reset something?

My DRO reads zero when I am physically in the middle of the part. PS not the same make as yours

Tony

Edited By Tony Pratt 1 on 30/09/2023 10:17:52

Can you explain how you are using it? I cannot find an online manual for this model.

I have an Easson display (also from M-dro) where the sequence is:

- Pick up one edge and zero axis readout

- pick up opposite edge and press 1/2 button.

That halves the value in the readout, which is the equivalent of putting zero at the mid-point of the work and works whether you initially zero at the + or - side of the work.

Is yours similar or does it work differently?

Nealeb, yes that is what I do, so what is your problem as your DRO will read zero when your mill spindle is over the part centre line? My DRO is a Knuth make.

Tony

Edited By Tony Pratt 1 on 30/09/2023 10:33:37

Hi Nealeb,

Find one edge and press the zero key for the appropriate axis (Y in this case).

Find the opposite edge and press axis selection key.

Press the 1/2 function key.

Display would previously have shown the centre of the part to be 0.000 (as it should), but now shows it as half the centre distance between the two edge finder positions.

Hope that's clear.

I think there's a button press missed out in the above sequence.

So, in Y:

Find one edge, press Yo

Find other edge, press 1/2 then Y (not Yo)

Move back to zero, this should be the centre.

Hope this helps,

Rod

Edited By Roderick Jenkins on 30/09/2023 11:05:47

Bo'sun

If you zero at the first edge, find the second edge the display should read the distance between the edges (plus the centre finder probe diameter).

If you them press the 1/2 function key the display reading should halve.

Winding back to zero should place the quill above the centre position.

Questions :-

1) Does the display reading halve when you press them 1/2 key?

2) Does the display count down to zero when you move back towards the middle or freeze on the 1/2 value?

If the reading doesn't halve when you press the 1/2 key odds are the key isn't working properly. Contact issue under the membrane.

If If the reading freezes and doesn't count down you may have entered a lock mode.

My Sino set up has a lock mode if I read the book correctly. Something I make sure to stay the hell away from as the potential for confusion is obvious. That said I can see various uses for it if you exploit the other memories. Transfer of dimensions to replicate feature in other places for example.

Clive

FWIW, my initial question was aimed at the OP - my own DRO works perfectly! However, as pointed out by others, I did forget the step of specifying the axis to halve - otherwise how does the DRO know which axis?

This does make me think, though, that the effect described in the original question could happen if you hit the "X0" button when you are selecting the axis rather than "X", say.

It is, perhaps, slightly misleading to call the "1/2" button the "centre finder". While that's what everyone uses it for, actually all it does is halve the value in the display, hence its name on the front panel. Really useful, all the same!

Clive,

I'll check this afternoon.

You've got the key press order reversed

Find one edge, say Y

Press Y0

Find the other edge

Press 1/2 followed by Y (not Y0)

Thanks duncan,

I'll try that, but it's not the sequence shown in the M-DRO manual that's worked previously.

Bo'sun I have the Mdro. I have just done a video & i show the edge finding on the dro. Its near the begining so you won't have to skip far. Hope it helps.

Steve.

Clive,

In answer to your questions:

1) The reading does not halve when the 1/2 function key is pressed. It stays on the Y (axis location) reading.

2) The reading does not freeze, but counts until the zero position is half of the two edge finder locations. ie; If the two edge finder locations are 24mm apart, zero (centre location) appears to be 12mm.

Duncan,

Changing the sequence does not work.

Thanks Steve,

That's exactly what I'm doing, but pressing the Y (axis location) key doesn't display "0" as shown in your video. I fear something may be amiss with the MDC700 unit. I'll see what M-DRO have to say next week.

Bo'sun

Pretty sure that the 1/2 key isn't working.

Clive

That 1/2 function is just a faster and nice to have (when it's working) item. But if the dro is still accurately measuring linear distances. You can still do exactly the same without that 1/2 function. Let's use the Y axis for example, accurately measure your part width, divide that in half. Edge find the part, move over half the distance of your edge finders tip. That puts your spindle center line directly over the part edge. Zero the dro's Y axis, now move over that half distance of the part you previously calculated for it's width. But I'd stress that accurately measure part. Caliper measurements for your part width can't and won't give you the same accuracy as the dro and that half function will. So micrometer measurements would be the better way if your part centering does require that level of accuracy. Analog hand wheel dials obviously haven't any half function either, so you just use the dro in much the same way as you would with those. Yes it will take just a bit longer, and there's a few other ways to do this, but will still allow you to do what you want until your dro issues can be resolved.

Thank you Pete,

A good suggestion to get the project moving. I'll give it my best shot after lunch.

On my M-DRO unit you have to use the ENT key after the 1/2 function. That then gives you the 0 point at the centre of the 2 readings.

Any help?

Andries

Thank you Andries,

I'll give it a try, but it's not what the M-DRO guidelines tell you to do. The problem is, all worked fine previously, but now it's just stopped working. Let's see what Allendale (M-DRO) have to say next week. Fortunately it's still under warranty (just).

Certainly seems like a fault somewhere.Hope you get results from supplier. They say they are very good & at least in the UK.

Steve.