Author Topic: Coax Indicator, designed by W.K.Todd  (Read 3237 times)

Offline fumopuc

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Coax Indicator, designed by W.K.Todd
« on: December 12, 2018, 11:05:45 AM »
Hi everybody,
I am trying to make one, here the slightly modified design and were I am today.
Kind Regards
Achim

Offline BillTodd

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Re: Coax Indicator, designed by W.K.Todd
« Reply #1 on: December 12, 2018, 12:19:30 PM »
Looks good,

 It's really a buzz to see someone making something I designed  :pinkelephant:

Were the drawing ok, were you able to follow my description?

Bill

P.s the pdf is on my google drive here:

https://drive.google.com/file/d/0BwXDcXKx2KzlaUVrZ0l6QU4yaTA/view?usp=drivesdk
« Last Edit: December 12, 2018, 12:22:33 PM by BillTodd »
Bill
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Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #2 on: December 12, 2018, 01:44:04 PM »
Hi Bill,
thanks for the link to your drawings.
It seems that I have downloaded the same set some time ago, I think via MadModder.
During the last summer I have redrawn everything in Fusion 360 and I have started the making now.
For me the information of the real shape and dimension of the rocker was a bit weak, so I have imported the picture into Fusion and the software has calculated everything by given the dimension of a known whole, 4 mm.
Progress will be shown here.
Kind Regards
Achim

Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #3 on: December 12, 2018, 02:36:54 PM »
... and the up date from this afternoon.
The two aluminum parts are fitted togther with some epoxy glue and cured in the oven at 100C.
My fingers should give an idea about the overall dimension.
Currently I am playing a bit with Fusion CAM.
Kind Regards
Achim

Offline Vixen

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Re: Coax Indicator, designed by W.K.Todd
« Reply #4 on: December 12, 2018, 03:52:18 PM »
Hi Bill and Achim,

This coaxial indicator looks very useful and has been added to my 'to do' list   :ThumbsUp: :ThumbsUp:

Do you find it more convenient to have the dial facing forward of facing upward? I am thinking about the view of the dial, when you swing it through 360 degrees.

Mike
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Online sco

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Re: Coax Indicator, designed by W.K.Todd
« Reply #5 on: December 12, 2018, 04:46:10 PM »
I've always wanted one of these so have added it to my 'To Do List' too!

Thanks Bill and Achim,

Simon.
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Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #6 on: December 12, 2018, 04:55:34 PM »
Hi Bill and Achim,

This coaxial indicator looks very useful and has been added to my 'to do' list   :ThumbsUp: :ThumbsUp:

Do you find it more convenient to have the dial facing forward of facing upward? I am thinking about the view of the dial, when you swing it through 360 degrees.

Mike


Hi Mike, with the M4 bolt a clamping in every position should be possible.
Kind Regards
Achim

Online b.lindsey

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Re: Coax Indicator, designed by W.K.Todd
« Reply #7 on: December 12, 2018, 05:08:45 PM »
Well the beauty of a coax indicator is that the dial stays in one place and doesn't swing through 360 degrees.

Bill

Offline Vixen

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Re: Coax Indicator, designed by W.K.Todd
« Reply #8 on: December 12, 2018, 05:13:00 PM »
Well the beauty of a coax indicator is that the dial stays in one place and doesn't swing through 360 degrees.

Bill

Thanks Bill,
I had assumed you rotated the dial gauge, but it seems you can also rotate the spindle and the dial remains stationary.

Mike :facepalm: :facepalm:
It is the journey that matters, not the destination

Online crueby

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Re: Coax Indicator, designed by W.K.Todd
« Reply #9 on: December 12, 2018, 06:19:06 PM »
I had to do a search on coax indicators, there are a couple of youtube vids that show them in action - pretty slick units.

Offline BillTodd

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Re: Coax Indicator, designed by W.K.Todd
« Reply #10 on: December 12, 2018, 06:22:52 PM »
Hi Bill,
thanks for the link to your drawings.
It seems that I have downloaded the same set some time ago, I think via MadModder.
During the last summer I have redrawn everything in Fusion 360 and I have started the making now.
For me the information of the real shape and dimension of the rocker was a bit weak, so I have imported the picture into Fusion and the software has calculated everything by given the dimension of a known whole, 4 mm.
Progress will be shown here.


Ok, perhaps i should have made it clear that the shape is unimportant  , except for the offset stylus mount, which reduces the overal height.

I was going to experiment with the shape of the sliding feet , so as to reduce sine error .
Bill
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Online b.lindsey

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Re: Coax Indicator, designed by W.K.Todd
« Reply #11 on: December 12, 2018, 09:46:36 PM »
Chris that are great for things like aligning the RT to the mill spindle. The only downside is they require a lot of headroom, but perfect for Bridgeport type mills.

Bill

Online crueby

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Re: Coax Indicator, designed by W.K.Todd
« Reply #12 on: December 12, 2018, 10:19:32 PM »
Chris that are great for things like aligning the RT to the mill spindle. The only downside is they require a lot of headroom, but perfect for Bridgeport type mills.

Bill
Having the taller column ony sherline, could work...   Hmmm...

Online b.lindsey

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Re: Coax Indicator, designed by W.K.Todd
« Reply #13 on: December 12, 2018, 10:30:19 PM »
Bill's design looks like it needs less headroom than my SPI unit. So yeah it could work with the taller column.

Bill

Offline BillTodd

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Re: Coax Indicator, designed by W.K.Todd
« Reply #14 on: December 12, 2018, 11:30:22 PM »
Bill's design looks like it needs less headroom than my SPI unit. So yeah it could work with the taller column.

Bill

I designed it to be as short as possible because the  vertical head on my Haighton mill has very little head room .
Bill
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Offline Art K

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Re: Coax Indicator, designed by W.K.Todd
« Reply #15 on: December 13, 2018, 02:40:11 AM »
I have one that I bought at the NAMES show and then didn't use for a few years. Set it up fairly close to center in a hole flip on the spindle and dial in the table til its centered, done. I bought it from little machine shop & use it at work a lot now.
Art
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Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #16 on: December 14, 2018, 12:38:53 PM »
Hi everybody,
here a picture of the standard low cost indicator and the version Bill has designed.
This big difference is the reason why I have started the build.
If someone is interested, here a video of making the rocker with Fusion360 CAM and my mini CNC mill.
Kind Regards
Achim

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Re: Coax Indicator, designed by W.K.Todd
« Reply #17 on: December 14, 2018, 02:48:28 PM »
Nice video Achim and that picture really shows the reduction in headroom required!!

Bill

Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #18 on: December 15, 2018, 07:51:32 PM »
Looks good,

 It's really a buzz to see someone making something I designed  :pinkelephant:

Were the drawing ok, were you able to follow my description?

Bill

P.s the pdf is on my google drive here:

https://drive.google.com/file/d/0BwXDcXKx2KzlaUVrZ0l6QU4yaTA/view?usp=drivesdk


Hi Bill,
Is there any type of spring between the bearing at the top and the housing ?

Kind Regards
Achim

Online crueby

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Re: Coax Indicator, designed by W.K.Todd
« Reply #19 on: December 15, 2018, 08:18:33 PM »
And if I am interpreting the drawings correctly, the tip of the dial indicator is pushed back by that 45 degree taper on the center shaft, as the shaft is pulled by? Any chance you could do a cross-section view of the assembled unit in the 3D model? Its tough to visualize how it all comes together.
Thanks!Chris

Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #20 on: December 15, 2018, 08:40:50 PM »
.. that was easy. :Lol:
The housing will be lifted.
« Last Edit: December 15, 2018, 08:44:40 PM by fumopuc »
Kind Regards
Achim

Online crueby

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Re: Coax Indicator, designed by W.K.Todd
« Reply #21 on: December 15, 2018, 08:48:08 PM »
That helps a lot - thanks!!!

Offline Steamer5

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Re: Coax Indicator, designed by W.K.Todd
« Reply #22 on: December 15, 2018, 09:26:57 PM »
And heres me thinking my list is looking like its going to get shorter!

Looking good Achim. And thanks to Bill for coming up with a neat design

Cheers Kerrin
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Offline BillTodd

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Re: Coax Indicator, designed by W.K.Todd
« Reply #23 on: December 16, 2018, 06:59:19 AM »
Looks good,

 It's really a buzz to see someone making something I designed  :pinkelephant:

Were the drawing ok, were you able to follow my description?

Bill

P.s the pdf is on my google drive here:

https://drive.google.com/file/d/0BwXDcXKx2KzlaUVrZ0l6QU4yaTA/view?usp=drivesdk


Hi Bill,
Is there any type of spring between the bearing at the top and the housing ?

Yes, it should be just strong enough to push the body back when horizontal, but not too strong.

The spring should be the same diameter as the bearing so that it pushes on the outer race , the bearing stops the spring being wound up as the spindle turns
« Last Edit: December 16, 2018, 07:07:06 AM by BillTodd »
Bill
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Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #24 on: December 16, 2018, 07:38:26 AM »
Looks good,

 It's really a buzz to see someone making something I designed  :pinkelephant:

Were the drawing ok, were you able to follow my description?

Bill

P.s the pdf is on my google drive here:

https://drive.google.com/file/d/0BwXDcXKx2KzlaUVrZ0l6QU4yaTA/view?usp=drivesdk


Hi Bill,
Is there any type of spring between the bearing at the top and the housing ?

Yes, it should be just strong enough to push the body back when horizontal, but not too strong.

The spring should be the same diameter as the bearing so that it pushes on the outer race , the bearing stops the spring being wound up as the spindle turns


Hi Bill
somethings like this is available of the shelf in SS, outer diameter is 21 mm and wire is 1 mm.
I will order one.
« Last Edit: December 16, 2018, 07:42:36 AM by fumopuc »
Kind Regards
Achim

Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #25 on: December 16, 2018, 05:18:39 PM »
A little step forwards.
Kind Regards
Achim

Online Dave Otto

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Re: Coax Indicator, designed by W.K.Todd
« Reply #26 on: December 16, 2018, 05:21:10 PM »
That looks great Achim!

Dave

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Re: Coax Indicator, designed by W.K.Todd
« Reply #27 on: December 16, 2018, 05:35:04 PM »
You are making fast progress Achim!! Looks great so far too.

Bill

Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #28 on: December 17, 2018, 01:07:19 PM »
Steamer5, Bill, Dave, Bill, Thank you.


I have got it nearly.
I do have a basic run out of 0,05 mm, which, I think, is caused by my laziness.
I did not follow Bills advice to turn the shaft in one piece between centers.
My shaft is made by  a 15 mm silver steel bar of the shelf.
At the turning operation, I could already measure a run out of 0,04 mm, which is now still visible plus some additional tolerances.
I will make the probe holder now and will see if I can work with this basic run out.
« Last Edit: December 17, 2018, 05:39:02 PM by fumopuc »
Kind Regards
Achim

Offline BillTodd

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Re: Coax Indicator, designed by W.K.Todd
« Reply #29 on: December 17, 2018, 06:45:32 PM »
that runout may be caused by surface roughness, (grabbing the slider part)  Try polishing the 45 section of the shaft
Bill
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Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #30 on: December 19, 2018, 04:02:40 PM »
Hi Bill,
thanks for your friendly advice, but if the bad and lazy maker of this build has a run out in his shaft surfaces already, than polishing will not help.


I have measured the conical surface of the shaft against the outer diameter again, and there is the problem and it will stay.


So I made a new shaft and everything is fine now.




Bill thank you very much for the design and the drawings.
« Last Edit: December 19, 2018, 05:42:03 PM by fumopuc »
Kind Regards
Achim

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Re: Coax Indicator, designed by W.K.Todd
« Reply #31 on: December 19, 2018, 04:36:04 PM »
Well done Achim, and a great video showing it in use too.

Bill

Offline BillTodd

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Re: Coax Indicator, designed by W.K.Todd
« Reply #32 on: December 19, 2018, 08:51:19 PM »
Great job Achim  :cheers:
Bill
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Online kvom

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Re: Coax Indicator, designed by W.K.Todd
« Reply #33 on: December 20, 2018, 11:12:29 AM »
Where do you find the attachment "bars"?  I have the SPI unit, but I'd like a bit wider selection of lengths.

Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #34 on: December 20, 2018, 11:47:33 AM »
Hi Kirk,
here a picture of my Chinese Version of the purchased CI.
The six bars/probes has been part of the delivered set.
Since this morning they do have a smaller brother.
I have made it by a short piece of SS and a 3 mm titanium ball with M 1,6 already in it.
The ball was available in in our local Piercing Studio, down the road.
Last picture shows the whole benefit in Z-hight now.
Kind Regards
Achim

Offline Vixen

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Re: Coax Indicator, designed by W.K.Todd
« Reply #35 on: December 20, 2018, 12:01:44 PM »
I have made it by a short piece of SS and a 3 mm titanium ball with M 1,6 already in it.
The ball was available in in our local Piercing Studio, down the road.

Brilliant idea Achim. An engineer will always find a way.  :ThumbsUp: :ThumbsUp:

Make sure it is a new and unused titanium ball, it's amazing what parts, some people have pierced  :censored: :censored:

Mike
« Last Edit: December 20, 2018, 06:01:14 PM by Vixen »
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Offline fumopuc

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Re: Coax Indicator, designed by W.K.Todd
« Reply #36 on: December 20, 2018, 06:07:41 PM »
I have made it by a short piece of SS and a 3 mm titanium ball with M 1,6 already in it.
The ball was available in in our local Piercing Studio, down the road.

Brilliant idea Achim. An engineer will always find a way.  :ThumbsUp: :ThumbsUp:

Make sure it is a new and unused titanium ball, it's amazing what parts, some people have pierced  :censored: :censored:

Mike


Hi Mike, no worries, the ball and the bar has been washed in acetone before the assembly.
Kind Regards
Achim

Offline BillTodd

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Re: Coax Indicator, designed by W.K.Todd
« Reply #37 on: December 20, 2018, 07:32:07 PM »

Hi Mike, no worries, the ball and the bar has been washed in acetone before the assembly.

BTDT  - stung like a b######d :censored:
Bill
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Offline Vixen

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Re: Coax Indicator, designed by W.K.Todd
« Reply #38 on: December 20, 2018, 07:42:14 PM »

Hi Mike, no worries, the ball and the bar has been washed in acetone before the assembly.

BTDT  - stung like a b######d :censored:

Ha ha. Acetone....a wise precaution. But it only stings if you were to use it for it's original intended purpose.

I have a Renishaw digitising probe which I use for edge finding and for centre finding. It uses a 3mm diameter ruby at the tip of the probe's stylus . They are  very expensive to replace, if (or when) you crash the probe. I can now use your brilliant idea of a 3mm titanium ball to make my own replacement probe styli.

It's kind of interesting that both Renishaw and the body piercing industry both use the same M1.6 threads.

Mike
« Last Edit: December 20, 2018, 09:29:10 PM by Vixen »
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Offline Jo

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Re: Coax Indicator, designed by W.K.Todd
« Reply #39 on: December 20, 2018, 08:03:09 PM »

Hi Mike, no worries, the ball and the bar has been washed in acetone before the assembly.

BTDT  - stung like a b######d :censored:

Ha ha. Acetone....a wise precaution. But it only stings if you were to use it for it's original intended purpose.

I seem to recall Mrs Meldrew used Tabasco sauce on Victor 1.

Jo


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Online Dave Otto

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Re: Coax Indicator, designed by W.K.Todd
« Reply #40 on: December 20, 2018, 09:21:31 PM »
Where do you find the attachment "bars"?  I have the SPI unit, but I'd like a bit wider selection of lengths.

Long Island has the contact points that fit the Blake, but their not cheap.

http://www.longislandindicator.com/p110.html

Dave


Offline petertha

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Re: Coax Indicator, designed by W.K.Todd
« Reply #41 on: December 22, 2018, 05:23:36 PM »
The compact design is very nice indeed. One thing I wanted to ask on these co-ax devices - is it considered OK to rest the ball inside a countersunk hole & do the spinning centering operation that way? In other words finding the center of the countersink? For normal centering I use a DTI just hand rotating around bore holes or circular bosses. The DTI arm is free to pivot confined to its single motion plane & you read the dial at different opposing positions, no rocket science there. But I think the only way I could measure a center drill pip is orient DTI into X position, lightly lower so the ball ts fully in the drill cone, raise, then repeat in in Y direction. That's a pain. I thought maybe co-ax could do this under power rotation by just resting the ball in the cone. However, now its constrained in the vertical direction. So would that bugger up the movement or give false reading?

Offline BillTodd

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Re: Coax Indicator, designed by W.K.Todd
« Reply #42 on: December 23, 2018, 12:04:42 AM »
 :slap: You can centre on a counter sink but it would be more accurate to drop the probe into the hole (with a suitable sized ball) . The pivoting nature of the probe obviously requires some vertical freedom.


My 3d probe would have been a better option, unfortunately it never worked well enough . I have another design (copy of the Haimer 3d taster) but have yet to find time to build it.

https://madmodder.net/index.php/topic,6998.msg75024.html#msg75024
« Last Edit: December 23, 2018, 12:15:25 AM by BillTodd »
Bill
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