Author Topic: Dial indicators on my lathe  (Read 19548 times)

Offline stefang

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Dial indicators on my lathe
« on: July 07, 2013, 05:28:31 PM »
Me again :)
As I am to cheap to buy glas scales for my lathe, I decided to mount a dial indicator to the cross slide and make a saddle stop with an indicator too.

Today I started the saddle stop with a sketch and a chunk of aluminum:


The contour was roughed out on the cnc with a shell endmill and some finish allowance:


Finishing was done with a nice six-fluter:


Chamfering was also done in that setup:


The backside then was faced of to thickness.

Roughing out the step where the prismatic cutout will be located:


Cutting the prismatic cutout that fits the bed of my lathe:


And if even fits :D


And with an indicator:


There will also be an adjustable hard stop to protect the indicator...

More will come soon :)

Stefan

Offline Fredbare

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Re: Dial indicators on my lathe
« Reply #1 on: July 07, 2013, 05:42:24 PM »
Nice work Stefan, thanks for sharing.

John

Offline vtsteam

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Re: Dial indicators on my lathe
« Reply #2 on: July 07, 2013, 06:07:02 PM »
Very nice!  :thumbup: :clap:
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline krv3000

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Re: Dial indicators on my lathe
« Reply #3 on: July 07, 2013, 06:24:00 PM »
well dun

Offline Stilldrillin

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Re: Dial indicators on my lathe
« Reply #4 on: July 08, 2013, 01:55:57 AM »
Very nicely done Stefan!  :clap: :clap:

David D
David.

Still drilling holes... Sometimes, in the right place!

Still modifying bits of metal... Occasionally, making an improvement!

Offline mosey

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Re: Dial indicators on my lathe
« Reply #5 on: July 08, 2013, 09:04:20 AM »
Very nice work on a lovely machine.
How will you clamp to the ways?
Mosey

Offline stefang

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Re: Dial indicators on my lathe
« Reply #6 on: July 08, 2013, 07:50:28 PM »
Thank you :)

Quote
How will you clamp to the ways?

With a clamping strap under the ways, pictures follow..

All parts of the bed slide stop. From left to right:
- Body of the stop
- Clamping screw
- Clamping strap (I welded a nut under it, as the material was a bit thin for a durable M8 Thread)
- Tommy bar for the clamping screw
- Hard stop


Assembled stop from the underside, the clamping strap is held in position with two pins to prevent rotation:


From the top:


On the lathe:



So far, so good, next the indicator on the cross slide :)

Stefan


Offline vtsteam

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Re: Dial indicators on my lathe
« Reply #7 on: July 08, 2013, 08:40:28 PM »
Well executed. Makes me want to make one!

Been away from the machines for too long working on the furnace. Making things that make the machines work better is so rewarding!   :thumbup: :thumbup: :clap:
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline mosey

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Re: Dial indicators on my lathe
« Reply #8 on: July 08, 2013, 08:45:26 PM »
Damned fine! Can't wait for the next chapter. Gorgeous finish.
Mosey

Offline Pete.

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Re: Dial indicators on my lathe
« Reply #9 on: July 09, 2013, 11:30:06 AM »
I like that.

If you make a set of vee-bottom gauge blocks, in multiples of the travel of your dial gauge, you can use them to sit on the vee  between the headstock and the gauge mount to give you a very accurate method of turning shoulders or bores to a certain depth from a face.

Offline stefang

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Re: Dial indicators on my lathe
« Reply #10 on: July 10, 2013, 05:17:54 PM »
Stepping on :)

Contouring the cross slide block:



Mounted on the lathe:



Time to do something else.. :)

Stefan

Offline mosey

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Re: Dial indicators on my lathe
« Reply #11 on: July 10, 2013, 05:22:48 PM »
What is the reason for using dial indicators rather than the micrometer dials on the cross slide?
Mosey

Offline Pete.

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Re: Dial indicators on my lathe
« Reply #12 on: July 10, 2013, 07:25:29 PM »
Very simply, the dial on the handle tells you how much it should have moved but the dial indicator measures actual movement.

Offline Meldonmech

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Re: Dial indicators on my lathe
« Reply #13 on: July 18, 2013, 04:31:10 AM »
Hi Stephan,
                        An interesting well made addition to you lathe, I have a Chester DB8VS lathe which has a bed similar to your lathe. Yes I will be making one for myself, glad you posted it.
                                                                                                   Cheers David

Offline Arbalist

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Re: Dial indicators on my lathe
« Reply #14 on: July 18, 2013, 05:28:40 AM »
 Nice job! :thumbup:

Offline Miner

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Re: Dial indicators on my lathe
« Reply #15 on: July 27, 2013, 05:45:20 PM »
Stefang,
Congradulations on a very well thought out and very well built design. I sure hope you don't mind a few thoughts though. Before today's common commercial quality and accuracy DRO's were even invented companies such as Moore Tools used the exact same idea on there more than very very very accurate Jig Borers and Jig Grinders. They even cast openings in there castings that after precision machining it then allowed the dial indicators to be dropped down into 'wells' that helped to protect them from most bumps, dropped tools, etc. Usually they added a hinged clear heavy glass or plastic door above the indicator to provide further protection. Also there was a side cut out that allowed the operator to spin the indicators dial like you can on most of them to zero it wherever you'd like without opening that top door.

But the indicators also used a very thin rubber set of bellows I'd guess you'd call them. One end was fixed to the round part on the indicators housing and the other end was a tight fit on the indicators plunger shaft. That kept any metal dust, swarf, or even cutting fluids from being sooner or later dragged up inside the indicators insides and ruining or at least partially ruining the indicators precision.The last time I checked Mitutoyo at least still sold those rubber bellows for indicators. Starrett might too, but I can't say for sure. The last time I did notice them they were very cheap.

But that Moore Jig boring equipment also used a set of machined U shaped holders, one dead in line and just in front of the indicators tip, and another aligned so it was dead straight at the fixed end. At that end there was also a pin that got screwed into the casting so it had a flat precision end much like an elephants foot that get's screwed onto an indicator's tip.So with an indicator with only 1" of travel, you could add what they called 'setting rods'. Those were basically the exact same thing as what are supplied with today's micrometers from the 2" range and up. So you can then just drop those micrometer gauges into those U shaped holders, butt one end up against that fixed pin and then end up with a very precise system at 1" increments. With the 1" travel on the indicator, you end up with a system that can accurately measure to the length of your machines travels and the range of micrometer gauges you have. I hope I've made this a bit clear for you.

Mosey,
The D.I.'s work exactly the same as what any add on DRO does. They don't rely on the dial or feed screws lead/lag inaccuracies at any point. Plus there's no need to compensate for any backlash. When it's set up right it's a direct reading system. If a slide moves? Then the system will show it. It does take a bit of time with it to get fast, but it's an excellent setup and was very well proven by at least Moore tools as I mentioned. Very high end digital indicators and quality gauge blocks would give you at least the movement accuracies of the best DRO's made. But you wouldn't have all those nice to have added in canned programs the average DRO has. And it's a lot slower to use with much more chance of making a mistake than a standard DRO. Personally I think it's a far better system that should be much more accurate than any of those Chinese bar type scales that aren't any better than a cheap digital caliper. YMMV. 

Pete   
« Last Edit: July 27, 2013, 06:16:48 PM by Miner »

Rob.Wilson

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Re: Dial indicators on my lathe
« Reply #16 on: July 27, 2013, 05:55:48 PM »
 :clap: :clap: :clap: :clap: Very nicely done Stefan   :thumbup:

One day I will get round to doing the same  :med:

Rob