Had a thought: is there a small version of a co-ax indicator for small mills?

RaisedByWolves

RaisedByWolves

Mangler of grammar, off my meds.
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Saw a video last night of a guy using a co-ax on a mini mill and was using my co-ax on a B-port today and got to thinking that for some situations a 1/2 size co-ax would be great to have.

Is there anything like this on the market?
 
A smaller-size coaxial indicator would be a nice thing. I have a standard size one and I've found that it can be too big for some things on my mini mill, uses up too much Z.

An alternative, something on my very long project list, is a holder for a DTI. It would look a bit like a trepanning tool but the cutter would be replaced by a DTI holder. Another way of looking at it is a variation of a "sweeper" for tramming your mill; but you'd want to be able to move the DTI from near-dead-center outwards.

One disadvantage of using a DTI is that the dial moves when you (hand) rotate the spindle. It can be hard to read accurately when facing the mill column so I've used a little mirror to view the dial in that situation.

The mill will need to be well trammed for this scheme to produce decent accuracy. And the gadget will have to be well made.
 
Homebrewed ................/\/\/\ Done this for my entire career . Large , small , long and short bars with DTI on swivel shaft . I've never owned a coax . Simple to use a mirror if needed . :) You actually don't need a mirror when tramming a hole . I indicate 0 and 90 degrees on both sides so I know 180 is good to go .
 
SPI makes / made a version of what you're describing. And Gem made a two-face DTI to eliminate the need for a mirror.

GsTspi.jpg
 
mmcmdl said:
Homebrewed ................/\/\/\ Done this for my entire career . Large , small , long and short bars with DTI on swivel shaft . I've never owned a coax . Simple to use a mirror if needed . :) You actually don't need a mirror when tramming a hole . I indicate 0 and 90 degrees on both sides so I know 180 is good to go .
Click to expand...
I have used and edge finder and my DRO also...
 
homebrewed said:
A smaller-size coaxial indicator would be a nice thing. I have a standard size one and I've found that it can be too big for some things on my mini mill, uses up too much Z.

An alternative, something on my very long project list, is a holder for a DTI. It would look a bit like a trepanning tool but the cutter would be replaced by a DTI holder. Another way of looking at it is a variation of a "sweeper" for tramming your mill; but you'd want to be able to move the DTI from near-dead-center outwards.

One disadvantage of using a DTI is that the dial moves when you (hand) rotate the spindle. It can be hard to read accurately when facing the mill column so I've used a little mirror to view the dial in that situation.

The mill will need to be well trammed for this scheme to produce decent accuracy. And the gadget will have to be well made.
Click to expand...
Ive acquired a top facing indicator with a back mounted lever similar to if a last word and a back plunger DTI had a baby. Federal testmaster?


Anyway, it goes on an indicol on the B-port and since the face points up its easy to read at most angles. I also got one of our engine ears to buy me a reversing mirror, but unfortunately its small and hard to read the indicator face in. A coworker had a GEM with the opposing faces which seemed nice.

There are some solutions for indicating a hole or pin, but the main thing I want to use this for is picking up a spot punch rather than using a wiggler when I need that level of accuracy.

I'm rolling around in my head how I can add an attachment to a best test or the like to do this, but I'm not there yet. This idea came about as I was showing my coworker how I use the co-ax without turning the machine on to find a spot or hole in a matter of seconds and he was floored buy how simple and fast this method is.


I need a wide range but short indicator to base this off of so I'm on the lookout for that, whether it will be plunger or lever style Im not sure but Ill know it when I see it. 0-50-0 would be more than enough as long as the user is careful.

Any input as to type/brand is welcome.
 
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verbotenwhisky said:
I wonder if you could simply fabricate shorter probes for your Co-Ax?
Click to expand...
You can, but it changes the accuracy somewhat.

How much I don't know, but I made a 6" probe that is "Perfect" in concentricity, shape and rigidity, but the result was less than spectacular.

I have it, Im proud of it, its "pretty" (Grey case coloring), but a sundial is nearly as accurate for Tool&Die work as the Blake is with this thing installed.

Ill post a pic tomorrow if I think of it.
 
RaisedByWolves said:
Saw a video last night of a guy using a co-ax on a mini mill and was using my co-ax on a B-port today and got to thinking that for some situations a 1/2 size co-ax would be great to have.

Is there anything like this on the market?
Click to expand...
As has been pointed out, there are alternate ways to do what a co-ax indicator does, but to your question, I don't think so. All of them I saw when I was shopping for one were pretty much the same size.

Tom
 
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