DOC or diameter with lathe DRO

[AGCB97]

I'm not unfamiliar with DRO as I have one on my Bridgeport but when using one on a lathe, on the crossfeed will I only be able to measure DOC and need to do the math for diameter? Not that it is difficult but just wondered about options on the DRO. Probably a stupid question I'll wish I had not asked!
Aaron

 

[DavidR8]

Not DRO related but the dials on my South Bend read diameter, so a .010 DOC on the dial equals that much reduction in diameter. It saves my brain from having to do decimal math on the fly.
If I had a lathe DRO I’d set it up to read diameter. I know that the DRO on my mill has that ability.

 

[AGCB97]

I guess that's what I was asking. So I need to make sure the DRO I buy has that ability.
Thanks
Aaron

 

[macardoso]

I definitely prefer the DRO to read diameter, mine can do both.

You need a pretty high resolution scale on the cross slide to read in tenths. I have a 1um scale which reads out in 1 tenth on the diameter, very handy. 5um is standard.

 

[mksj]

Most DRO's have a diameter function, some have what are called soft keys that can be programmed differently depending on the DRO initiation settings when you set the machine type (mill, lathe, etc.). The are also machine specific DRO's that the keys are specific to the type of machine application (universal display vs. machine specific). I would wager that the majority of DRO's have a diameter function, but it is something I would check before purchasing.

Electronica

 

[Winegrower]

I find that I switch back and forth from radius to diameter depending on the part, the feature, the tool, etc. And sometimes it’s easier and quicker to read and move the dial directly.

 

[mmcmdl]

Not DRO related , but our 13" Colchester's dials are DOC , so double the diameter decrease . I hate the darn thing . It's the only lathe I've ever seen having this in 40 or so years .

 

[BGHansen]

Not adding anything that isn't already typed above. I have a TPAC Tools DRO on my G0709 lathe which does both radius or diameter. I leave it on diameter. I believe TPAC used Ditron or MTech at the time. They're all pretty much the same at this point so you'll most likely have both. But it doesn't hurt to ask.

Bruce

 

[rwm]

Not DRO related , but our 13" Colchester's dials are DOC , so double the diameter decrease . I hate the darn thing . It's the only lathe I've ever seen having this in 40 or so years .

I did not know this was the norm. I have moved from a Sherline to a 9x20 Asian to a South Bend 10K. All of those crossfeed dials were depth of cut. I think I would really screw up now if I went to diameter dials.
Robert

 

[RJSakowski]

Some DRO manufacturers differentiate between a mill DRO and lathe DRO with the features that they offer. A lathe DRO has no use for a bolt circle function but will offer a radius/dimeter function. Make sure when you select one that it is intended for lathe use.