Homemade DRO's?

[johnnyd]

http://www.yadro.de/

Found this over on the "General" forum & thought I would share.

[Davo J]

With glass scale DRO's coming down in price every day and the accuracy they give. It makes you wonder if it's worth making one, thats unless it's the challenge of building it your after.
Davo

[macona]

And then there is the delay in the updates from the digital calipers. There is a fast mode where it updates faster but I think you loose accuracy when that happens.

[John Stevenson]

I had a Shumatech fitted to my lathe for a while but got so fed up of it dancing on the display I swapped it for a glass scale unit.

Another lathe problem is they are good for 0.001" reading but on a lathe because of the diameter it then becomes 0.002" at best, 0.004" at worse and to be honest you get get better on dials.

They were acceptable when DRO's were $$$$$ but it fast reaching the point where the kludge up are equalling the glass scale imports.

.

[loose nut]

The cheap digital scales don't compare well to the glass scale DRO's

[The Artful Bodger]

Just how good are DROs on a lathe anyway? Can you skip the caliper and micrometer stage?

I have cheap caliper type scales that I operate from tensioned wires to indicate saddle and cross slide movement and these are at least as reliable as the knob graduations but I still need a micrometer or gauge to finish, are expensive DROs any better than that?

[Jim Shaper]

My heidenhain DRO on the lathe is every bit as accurate as a caliper once you calibrate it to the cut you're taking.

For instance, you're boring a hole. You set your tool, take a test cut, measure your diameter, set the DRO to the measured diameter. Next cut so long as your tool is rigid enough for the depth, or you're not taking such a light cut as to rub and not cut - it'll be spot on the money. Just like setting up tools on a cnc, the repeatability is only as good as the data input.


I couldn't work anywhere near as fast as I do without my DRO.

[macona]

Yep, a good dro is an incredible time saver and scrap saver. No counting handwheel turns! And like Jim says, with a good solid machine you can repeat 10ths on multiple parts. And turning shoulders is so much easier since very few machine even have dials on the carriage handwheel.

[The Artful Bodger]

I would not know just how accurate my cable arrangement is as so far I do not even have a micrometer but in one test I turned a band on a shaft, retracted the cross slide and moved the carriage along then using the cable DRO I reset the tool position and turned back to join the first band. The join was visible but I could not feel it, I figured in that instance that it was 'pretty good' but I have no idea of the numbers.

Maybe I will be able to justify a good DRO one day but meanwhile even this simple system is worth it for the way it avoids gross errors.

[loose nut]

Tiffie is right in one respect on this subject, a DRO will get you 99% of the way there but the Micrometer gets you the rest of the way.