DROs for mill & lathe

[ariz]

I spent the last weeks (well, the week end only) to install Digital ReadOut system on my mill and lathe. 5 pieces, 3 for mill and 2 for lathe.
the work wasn't too difficult, apart for the Z axis of the mill and the X axis of the lathe (I suppose it's the X axis, anyway it's the cross slide)
I didn't take pics of the work, because it was a matter of simple drilling and milling job, but today, after having completed the task, I took pics of everything

mill Z axis



mill X axis



mill Y axis



lathe, pics all together

















in a first time I made this support for the cross slide DRO, to protect it (I wanted to partially cover it with a transparent piece of plexyglass)



but it was too flexible (the L shaped aluminium bracket is 3 mm in width) because it is fixed only at the centre of the cross slide and the DRO protrudes outside for the whole lenght. I wasn't satisfied and so I changed the project, I hope that the DRO, being away from the chuck, doesn't catch too many dirt.

I know that the position of this DRO isn't many comfortable, it would be better on the opposite side of the lathe, as people generally install it
but the Boley lathe has a vertical rod in the middle of the other side, that supports the lever to start and stop the motor, so this solution was impracticable.
the first tests that I have made today aren't so bad, it seems that I could drive the lathe as easy as before

all DROs but the Z axis of the mill are OK, and readings are the same as the collars suggest.
on the Z axis of the mill instead I have a little difference, must investigate on this (I was so proud just of that DRO, it was installed in a perfect manner that everything was invisible, but obviously it is the only one that has problems  )

[sbwhart]

Hi Ariz

Good work looks like you've got some real nice kit, apart from working on your machinery what else do you make.


Thanks for showing

Stew

[kvom]

Those will be useful! 

I think I might get a backache reading the mill y-axis though. 

[sorveltaja]

Ariz, are those units sold separately, or did you make them off of calipers? As my digital caliper has very similar looking DRO, as on pictures 2 and 3...

[ariz]

thank you guys

well, Stew I'm almost a newbe in the model engines making... I found the HMEM group about an year ago and from while I bilt a couple of steam engines and now I'm working on the third, an IC engine
I discovered this group some months ago and I like it very much too

you're right kvom, that y-axis DRO isn't the most practical 

sorveltaja the units are sold as you see them: they are cheap, I bought them on ebay for about $ 30 each. but you're right, the horizontal ones are identical to the common digital calipers, while the vertical ones are a bit more sophisticated (not much anyway), in fact they are priced a bit more than the horizontal

[Jonny]

I done exactly the same on my smaller mill some years back before the prices dropped.
24" scale was £110 cheap then. 3 axis plugged in to 3 way Warco display which i dont recommend at £150, plus drains the batteries even more so.
Did buy a 6" caliper £5 from Aldi just to replace one of the units that got wet.
Cost me a fortune in LR44 batteries, all scales packed up years ago due to coolant, sorry for me was a waste of £300+ with display can get a decent coolant proof proper DRO for £400+.

I would rearrange the quill scale, you will get different readings certainly not accurate as its not rigid coming off the depth stop marker and play in the thread. Quill casting to bottom of scale bracket direct, you can fix rigid and stationary the scale via a bracket, dont need top fixing this will move with quill. Have a look and check for rotation of quill, may be make up a larger better fitting guide to stop it, had to do it on bigger mill but not the smaller.

Why such a long scale on the top slide, only ever use mine for cutting angles.

[ariz]

thank you Jonny
well, the pic doesn't show it, but I didn't use the original depth stop with a huge play in the thread to fix the scale.
I made a new one, with very tight joints, that hasn't any play at all.
anyway I'll try to do as you suggested.

the scale of the top slide (on the lathe) is 200 mm long
I use the top slide near always to turn pieces that don't exceed that lenght, because the movement (with collar) is smoother than that of the carriage (with rack and pinion)

[bogstandard]

Just as a side note Ariz.

If you are using your topslide for turning instead of the saddle movement, you must clock up your topslide fairly regularly, to make sure it is running truly parallel with the bedways, otherwise you can easily end up with the jobs you are doing having a taper on them.


Bogs

[ariz]

absolutely truly Bogs!

I discovered this sometime ago, because I cannot turn a piece in a decent manner: all were tapered!
and the top slide was not correctly in line

anyway thank you Bogs, this is also a vital point to remember for anyone that uses the top slide like me


p.s.
the Z-axis scale of the mill is ok, the error stayed in the quill collar: it engages with a gear in the rack of the rapid movement of the quill (I don't know the exact words to use), but the 3 short screws that block the ball bearing cover were worn. replaced with 3 longer screws, everything is all right now

[Jonny]

Additionally you cant rotate or change tool posts very well with that top slide jobby. Dont take this the wrong way its your tool but the Y axis sticking out certainly would get in the way.

Never got round to slapping a DRO on the bigger lathe, X axis very easy its the cross slide where the problem arises as i couldnt afford to lose any holes in front or behind carriage. Only way was to mount outboard over swarf tray with rigid bracing off saddle.

[Darren]

Your cross/top slide is identical to my Smart & Brown (mines the copy btw)

As much as I would like to fit a DRO as you have done, I wouldn't like to loose the quick removal of my tool post.

That was the first thing that crossed my mind seeing your original post.

[ariz]

Jonny and Darren, thank you for having posted your comments sincerely
I haven't understood them completely, because of my lacking english language

what I can say is that this solution came to me after having tried every other solution...
- the cross slide scale can't stay outboard away from me, because there is a vertical rod that collides with it
- it could be installed on the right hand side of the cross slide (in the centre, without protruding outboard), but I didn't want to sacrifice space to the tailstock
so this one was the only position available

as regards the compound rest, I can manage the tool post well enough to me, almost like I did before
anyway I didn't make any new hole in the lathe cast, everything is screwed into existing threads and both the scales can be dismantled in seconds
 

[bogstandard]

Ariz,

Even with the big boys toys, problems can occur. I had to do some very fine trimming of the outer cover to get mine to be useable.

If you are happy using it the way you do, then there is no need to explain yourself.

Just enjoy what you have achieved, and feel proud of it.


John