Can you use a telescoping gage to measure gaps?

[Pcmaker]

I just bought this set

Amazon.com

I know these are normally used to accurately measure hole diameters, but can these be also used to measure gaps?

For example, I needed to measure the distance between a DRO bracket I made and the wall of my mill. I was thinking of using gage blocks to measure it, but I ordered this set of telescoping gages instead. I needed an accurate way to measure hole diameters of the pieces I'm turning on the lathe anyway.

If it can also measure gaps, it would be a bonus.

 

[higgite]

You can, but the problem is holding the telescoping arms perfectly perpendicular to the sides of the gap while you sweep it. A better way, IMHO, is to use adjustable parallels.

Tom

 

[gradient]

+1 for Higgite. I was just going to say the same thing.

 

[Chewy]

You can if your careful. Just did that measuring the T slot width on the mill. The parallels work better because they will usually stay there vs. the snap gauges moving around.

 

[JRaut]

I echo what everyone has said so far. Can be done if you’re careful. Make sure you get a repeatable number before you go forward with it.

Adjustable parallels are probably easiest, if you’ve got them.

You could also just use stacks of gage blocks if you’ve got those, though it’s a little more time consuming and finicky than adjustable parallels.

 

[mmcmdl]

For larger things , you can't beat a planer gage .

 

[NCjeeper]

For larger things , you can't beat a planer gage .

I was going to say planer gauge also.

 

[Mitch Alsup]

Telescoping gauge gets you close, adjustible parallel gets you closer, gauge blocks takes you to the top.

 

[Meta Key]

From ancient Starrett literature:



-MK

 

[Chewy]

Beware of Radius!! Just did the adjustable parallel measurement of the key slot in a Grizzly Rotary Table. The slot was very shallow, maybe 1/8 ". Got conflicting readings between slots. The slots varied from the dial calipers way too much and also there was a .007 difference in slot width.
Two things. I put an .011 feeler gauge under the parallel and that raised it up enough that the sharp edges of the parallel didn't touch touch the corner and then it matched the caliper. Cut the keys to the wider of the two and they fit the slot perfectly on one side and most of the way on the other. There was some kind of protrusion that was in the slot, that I couldn't see, but a file took quick work of that. Also took the file to the edges of the keys and they fit perfectly. Just beware of radius on inside corners when measuring.