Indicator pairing question...

[Air21]

...so in the shop I pinch hit as a mill and lathe operator (I am usually running 1 of three hones). The company provides .0005 dial test indicators for each station, and there are a handful of. 001 travel indicators available as well. Test indicators are a mix of Bestest, Shars and Aerospace, travel indicators are all chinese.

A typical setup uses the test indicator to level the workpiece and center on a bore which sometimes requires the indicator needle to be at an atypical angle, so without accounting for cosine error it isnt accurate for measuring .0005 but it is a valid comparator. The travel indicator is usually on the ways to set a repeatable 0 so I can dial the table out andit a bore gage in my hole then dial back without having to indicate my part again.

Im looking to buy some of my own indicators since I know I wont be here forever and my question is, is .0005 test/ .001 travel combination the standard? Or would I be better served with a finer resolution travel indicator especially if the prices and quality can be comperable?

What do you guys use?

 

[larry_g]

As always, it depends. The precision required will be dictated by the project your working on. The measuring tool you use should be at least 10x the resolution of the tolerance your working with.

That said you seem to have the understanding of what your are doing and I would say yes to your question of using a .0005 test indicator and a .001 for a dial(travel) indicator. Only you know the tolerance of the project your working on and that is going to determine if you need something else to measure your work with.

lg
no neat sig line

 

[Grigg]

Depends on the type of work you do.

I think most machinist can function with or would enjoy having a common 1" travel 0.001" resolution indicator. Also a Starrett 0.200" travel "button indicator" model 196 and the model 196F attachment for easily indicating a bore. Along those lines I like attachment 670B for the 1" indicator too.
Then you may also like a dial test or "last word" indicator with 0.0005 or even 0.0001 graduations.

I find useful but not a necessity a normal AGD type indicator (same style as your common 1" travel already mentioned) with 0.0001" graduation and at least several thouthanths travel.

Those first two mentioned do most all I need, the 196 and the attachments for it perhaps the most used.

Grigg

 

[Air21]

Wild, how do you use those hole attachments? :/

 

[tdkkart]

Unless you have an application that requires .0001" resolution, the aggravation it will put you through is crazy. If you can get by with .0005 you'll be much happier.

 

[Grigg]

Wild, how do you use those hole attachments? :/

I usually use them in the lathe when indicating the bore of a part true. They make it easy to see the dial as well as reach in a little bit from the edge.

I agree with only using as precise an indicator as you need, saves aggravation and less risk of damaging the more expensive ones. Sometimes I get close with a 0.001 indicator then switch and finish adjusting a part true with the 0.0001 indicator.

Grigg

 

[Air21]

Now that I looked up some pictures of that hole attachment, why do you use that instead of a test indicator?

 

[zkling]

A 0.0005" dial test indicator and a 0.001" standard dial indicator will do most general work. A 0.0005" dial indicator can be handy as well as a long travel indicator.

Unless you have an application that requires .0001" resolution, the aggravation it will put you through is crazy. If you can get by with .0005 you'll be much happier.

Agree. I don't pull out the 1/10 untill the 1/2 is barely moving. Otherwise you will be pulling your hair out.

 

[Grigg]

Now that I looked up some pictures of that hole attachment, why do you use that instead of a test indicator?

For more travel, more range on the dial, and a sturdier (less delicate) indicator, better on rough surfaces too.