Groove Micrometer Options

[VizRHCP]

Hello,

I'm looking to measure some depths and widths of an internal groove (.129", .383", .502"). I was thinking of using a Mitutoyo groove micrometer (146-131) but the smallest flange diameter is Ø.25" and the opening on my part is Ø.243". Does any one know of any other options out there that might fit these dimensional constraints? I'm looking more for handheld tools rather than 2D height gauges or CMMs. I've also thought about turning the flange piece to fit my needs.

Refer to model 146-131:

https://www.itm.com/pdfs/cache/www.itm.com/146-222/datasheet/146-222-datasheet.pdf

Any advice would be of help.

Thank you,

Andres

 

[guythatbrews]

This is a handy little depth micrometer attachment, but the disc is .250 diameter also. It could easily be ground down, and not as painful as grinding a $$$ micrometer. The disc is .025 thick. They also make them for 5/32 rods.

https://www.mscdirect.com/product/details/02197788

Maybe someone else makes them with smaller discs. I don't think you'll find anything cheaper.

 

[jccaclimber]

Would a Mitutoyo 209-935 or similar work?
I don't see a tolerance on that feature, but if it's generous then a groove caliper might be sufficient, or make your own clamp on tips to put on an existing caliper.

 

[jccaclimber]

Edit, rereading the post, you're never going to measure the 0.502 with a tool that extends from the centerline. It needs to overhang (0.502-0.243)/2 = 0.1295". Your distance from center is only 0.243/2 = 0.1215". You'll need something that crosses center when it collapses.

If it's a really small quantity you could stick a coax indicator in there, then take it out and put it between known gage blocks or a ring gage to compare, but I wouldn't want to do that for many parts. How does the customer use it?