Lathe X Dials, Radius, Diameter, Count Up, Count Down

[laminar-flow]

As far back as I can remember, I have used lathe dials that were diameter reading. Most of these were what I call reverse reading and count up when making the part smaller in diameter, which measures how much material is removed in diameter rather than the actual diameter of the part. When I acquired my Monarch 10EE around 1990, it had dials that had two sets of numbers on it that went the other way around. What a dream as one could do a cut, measure the diameter, then set the dial to that diameter. But apparently this was not the way Monarch intended because the accumulator dial on the X read the other way. Anyway, I used the Monarch like that until I installed a DRO which I set up to read Diameter and the part size, not how much material was removed. I do have a Schaublin 70 and it read in diameter but measured the material removed, not the part. I then made a new dial to read the part, not the chips.

Schaublin Dials, why are they backward in X and some are Radius instead of Diameter

After dealing with my Schaublin 70 English dial reading the material removed diameter instead of actual diameter of the part, (I would always use it to show diameter of the part by thinking of a 8 as a 2 and a 6 as a 4, etc.), I finally made a new X dial. I also have a Metric Slide and not only...

www.practicalmachinist.com

Then I saw a Schaublin 102 slide that not only had "reverse" reading dials, but it was in Radius. What a complicated thing to use. Yes, it can be done, but you need paper and a calculator close by. The 102 was then set up with a DRO that read Diameter and what the part was, not what was cut off. What a dream.

Does anyone know of lathes who's X dial reads diameter and the part? In other words, count down when approaching the centerline and in radius?

Every CNC lathe I know including mine is set in diameter and the work is the centerline and zero. An X adjustment of plus 0.010 makes the part 0.010 larger.

Any historical conventions would be nice to know also.

 

[Ralph_P]

Quote: "An X adjustment of plus 0.010 makes the part 0.010 larger"

I'd like to see a video of that.

 

[William Lynn]

Some CNC lathes can toggle between radius and diameter. At one time, our shop had two small manual Hardinge lathes, one had the cross feed in radius and the other diameter. Cut, measure and remember. And if you can't remember, mark with a Sharpie.

 

[AlfaGTA]

Manual machine dials have limited range unlike a DRO or CNC control.
Pretty hard to keep track of say cutting a 2" diameter step in an 8" diameter part on a dial trying to gauge by diameter..
Most machinists working manual think in terms of depth of cut, derived from material setup and tooling.....Hence the dial that registers in counting "up" when moving
into the part.
Cheers Ross

 

[bigjon61]

Quote: "An X adjustment of plus 0.010 makes the part 0.010 larger"

I'd like to see a video of that.

You're joking right?

I feel like people are on one side of the fence or the other with the DRO. I like to set it to work in the actual diameter of the part. I admit though, in our shop, I am the minority.

 

[David Ferguson]

I too would like to see a video of a dial that allows me to make an existing part 0.010" larger... That could come in handy.

 

[laminar-flow]

That was quite funny. It is the next CNC part that gets larger in Ø. In the 80's I used a Southbend that had a diameter dial but it read material removed. Hated it. Always read a 9 as a 1, 8 as a 2, etc. so I could set it to the diameter of the part and proceed. That is how I used my Schaublin 70 before I made a new dial.

 

[John Garner]

I'm not a fan of micrometric collars (commonly "dials") that are diametrically numbered, but I've been able to use them on cross slides.

On compound slides, diametric numbering is abhorrent simply because it is only diametric when the compound slide travel is parallel to the cross slide travel. I want to know how far a compound slide actually moves, no matter which way it points.

Feel free to take these comments with the proverbial grain-or-pound of salt; as I've said many times before, nobody has ever knowingly paid me to run a machine tool.

 

[TGTool]

I make quite a few larger, replacement dials for a lathe that cannot be named here. People just have their own, preferred way of working so they can get standard (100 graduations) or direct reading (200 graduations) dials. No argument. You want it, you get it. Now I know that most of these customers are small shops with a single lathe, so if they know their equipment there's no confusion.

It's trickier if you work in a shop with multiple machines that you have to use and some are one way and some another, especially with a "different" machine you use infrequently. Yeah, I know there are a lot of tougher problems in shops but sometimes it's the little aggravations that get to you.

 

[laminar-flow]

So can anyone think of a lathe that has the X dial read the diameter of the part and not the diameter of material removed?

Recently I made a bunch of parts on my 10EE using the DRO and datums for the two tools I was using. All my DRO's read Diameter of the part. Skim cut, measure the stock, set X & Z, set the datums, and go. Part diameters are what the DRO X reads. Switch tools and recall boring bar datum. Bore is the number on the DRO.

I used to do the same with the 10EE dial before I had DRO. Just had to use a sharpie mark on the dial for the boring tool datum. The 10EE dial has a reverse set of numbers but the Accumulator on the X reads material removed so I guess I was using it "backwards".