Digital readouts on a manual lathe ? Thoughts Please

[wood2steel]

I have to agree Moonlight,
I'm very content with Z axis only on the Leblonds and the older L & S's but I'm betting there's a pretty good chance the new kid in house ( L & S 20" Powerturn)"will be tricked out with all the bells and whistles before she's done. Only seems fitting!!

 

[sfriedberg]

Here's another strong vote in favor of 2-axis DRO on manual lathes, and another "don't bother" for the compound slide.
While I come to a different conclusion about DROs than rons, the issues he talks about are real. You cannot just dial in a random cut using a DRO and expect the part to magically come out to those dimensions. People do "spring passes" for a reason. Deflection (and lathe wear) is a real thing. And roughing passes will generally deflect the cutter and slides more than finish passes, so the discrepancy between DRO and actual part dimensions will vary depending on what you are doing. So you still have to have some experience running a lathe generally, and some experience using that particular lathe to know what you are going to get actually when you make a given move on the DRO. Nonetheless, I find a two-axis DRO to be a massive timesaver.

 

[Conrad Hoffman]

FWIW, I can run our HLV faster with dials than using the DRO. It depends on how good the dials are. Wish I had a DRO on other lathes that have a bit cruder dials. The DRO is also great for larger/longer parts where keeping track of revolutions leaves you open to errors.

 

[Newman109]

Two axis is plenty on a lathe. I learned to machine on my lathe using the dials. After about 20 years I added a two axis DRO and realized that, while it's nice, it's not going to change the basics of machining for you.

 

[rons]

For some DRO'ers.

You a using inserts and going happily on your way. Then one insert chips. Whether it is because of heat or you accidentally bang it.
If you screw in a brand new replacement insert, are all the DRO number positions still good?

 

[eKretz]

For some DRO'ers.

You a using inserts and going happily on your way. Then one insert chips. Whether it is because of heat or you accidentally bang it.
If you screw in a brand new replacement insert, are all the DRO number positions still good?

Close enough for roughing. Always take a semi finish cut before finishing to adjust for tool pressure. Not even remotely a problem.

 

[mike44]

I recently acquired an old manual lathe.
I was thinking about adding a digital readout. I don’t have much machining experience so I am wondering if adding more than the basic 2 axis would be worth doing. Like the carriage and cross slide are given but what about a dro on the compound slide and tailstock ? Is this something a person would use much just a waste of time and money. I don’t have much experience on a lathe so I don’t really know. Thank you so much for your experience and input for a newbie.

Place an O-ring on the tailstock quill. When you advance the quill you can measure the distance. Costs almost nothing and works well. As far as a digital readout , I do not have recommendation , but do not even consider I Gauging crap.

 

[wood2steel]

I have to weight in again with the key statement Ron's made; rigidity of the machine makes all the difference as to whether the crossfeed digital reading will be accurate. When I make a sizeable cut with the L & S and back the cutter out I rarely see a score line on the material; make this cut on the 15" Leblonds or Southbend and there will routinely be a score line on the stock which translates into error if you were approaching a .001 or .0005 target. I'm betting you guys running the Pacemakers, Axlesons, Monarchs, etc will agree the same. Gotta love those Machines with some meat in them! Still got to have that Z axis no matter what!!

 

[eKretz]

I have to weight in again with the key statement Ron's made; rigidity of the machine makes all the difference as to whether the crossfeed digital reading will be accurate. When I make a sizeable cut with the L & S and back the cutter out I rarely see a score line on the material; make this cut on the 15" Leblonds or Southbend and there will routinely be a score line on the stock which translates into error if you were approaching a .001 or .0005 target. I'm betting you guys running the Pacemakers, Axlesons, Monarchs, etc will agree the same. Gotta love those Machines with some meat in them! Still got to have that Z axis no matter what!!

Every machine will move a bit under heavy load, the X DRO is accurate on every machine I've ever run... That is why tool pressure must be compensated. It isn't difficult to do. If you're not doing it, you're not working as accurately as you could be. Don't blame the machine or the DRO for that. The tool pressure can change drastically just from tool geometry. No matter the machine.

 

[triumph406]

To my mind in this day and age, running a BP without a DRO would be borderline insanity.

So why would a DRO on a lathe be any different?

 

[Nmbmxer]

I've always wanted a readout on the tailstock, my lathe's TS dial is about useless and the quill is marked every .200" which also isn't all the helpful.

The carriage on that same lathe also has a useless dial, each division is .080" and a whole turn is an equally difficult number to count in your head. A 3 axis DRO is in that machine's future, but it's behind some other accessories for other machines that I want more.

 

[Conrad Hoffman]

Hint on old unmarked tailstocks. Most have a 0.1" pitch, so just by looking at the crank/dial you can hit the cardinal points and hit 0.025", 0.050", 0.075" and 0.1" within a few thou. With practice you can estimate in between fairly well too. I'm not proud- a taped on scale works well until it gets dirty or falls off!

 

[eKretz]

My lathe's tailstock has a friction hold handwheel that reads direct in .001" graduations and .100" per rev - that is handy. I sometimes bump the tailstock against the carriage at a set 'Z' on the DRO to get easily repeatable tailstock tooling depths also.

 

[rons]

My lathe's tailstock has a friction hold handwheel that reads direct in .001" graduations and .100" per rev - that is handy. I sometimes bump the tailstock against the carriage at a set 'Z' on the DRO to get easily repeatable tailstock tooling depths also.

Imagine how it would be without a DRO. Just cranking on that wheel all day.
Without a DRO I have to stop/start more often to check work.

 

[WakelessFoil]

I recently acquired an old manual lathe.
I was thinking about adding a digital readout. I don’t have much machining experience so I am wondering if adding more than the basic 2 axis would be worth doing. Like the carriage and cross slide are given but what about a dro on the compound slide and tailstock ? Is this something a person would use much just a waste of time and money. I don’t have much experience on a lathe so I don’t really know. Thank you so much for your experience and input for a newbie.

For most jobs a 2-axis DRO works splendidly. Most if not all lathes have hashmarks on the handles so you can get pretty accurate with those if you learn how to accommodate for backlash. I would be happy to have a DRO on cross slide and saddle (X and Z).

 

[trevj]

I've always wanted a readout on the tailstock, my lathe's TS dial is about useless and the quill is marked every .200" which also isn't all the helpful.

The carriage on that same lathe also has a useless dial, each division is .080" and a whole turn is an equally difficult number to count in your head. A 3 axis DRO is in that machine's future, but it's behind some other accessories for other machines that I want more.

What do you do with the TS that you need accuracy for?

And, can you do that with a tool post held tool?

I had a Schaublin 150 in the last shop I worked in, and we did just fine with two axiis.

The compound was really only unlocked when we needed a chamfer, or a threading infeed angle.

About every hole I ever drilled with a tailstock, was adequately covered by measuring out on the drill bit, and marking it with a Sharpie, or a bit of tape! Things that required more than that, got bored out!

I know I would not be happy with only the Z axis as a DRO, but I have not yet encountered an occasion that I thought I really needed more than two axiis to get things done!

 

[Nmbmxer]

What do you do with the TS that you need accuracy for?

Drilling out waste material for boring, I don’t like accident crashing a small boring bar into the bottom of a blind hole.

I’ve never drilled much with the carriage w/ a manual lathe. Seems like a lot of effort to get the drill on center (w/o a dro) and square vs plopping in a tailstock drill chuck. I generally set the quill with one of the graduations lined with the housing, bump the drill into the part by sliding the TS, run the carriage up to the TS and lock it. Then I can clear chips by pulling the TS back and just push it forward until it bumps the carriage and not lose track of my depth.

With a dro and the compound replaced with a plinth that pins the toolpost square I would probably drill with the carriage all the time. I don’t have either of those though on any of the lathes I regularly run.

 

[Tyrone Shoelaces]

Drilling out waste material for boring, I don’t like accident crashing a small boring bar into the bottom of a blind hole.

I’ve never drilled much with the carriage w/ a manual lathe. Seems like a lot of effort to get the drill on center (w/o a dro) and square vs plopping in a tailstock drill chuck. I generally set the quill with one of the graduations lined with the housing, bump the drill into the part by sliding the TS, run the carriage up to the TS and lock it. Then I can clear chips by pulling the TS back and just push it forward until it bumps the carriage and not lose track of my depth.

With a dro and the compound replaced with a plinth that pins the toolpost square I would probably drill with the carriage all the time. I don’t have either of those though on any of the lathes I regularly run.

The lathe you saw the most out in the field with a facility to drill off the crosslide was the “ DSG “. If I recall correctly those lathes were fitted with a device that the held the drill square and another device that automatically centred up the drill. I can’t recall exactly how it worked now but I know it was simple to use and it got the drill bang on right away.

Regards Tyrone.

 

[sfriedberg]

For most drilling on the lathe I use the tailstock quill, but I do have a few jobs where I prefer to use a 5C collet holder block that fits my CA Aloris/Dorian type toolpost, rather than a drill chuck on an arbor in the tailstock. Assuming the toolpost is square to the centerline (which is were I normally leave it) and the height adjustment on the block is OK (which it usually is), then getting a drill on center is just a matter of dialing it in on X (which is pretty quick).

 

[IceCzar]

Properly center the tool
2 axis is all you want.
running up to the chuck, count down (set your zero at the stop)
pull your power feed short and manually take the last bit.