measuring snap ring grooves etc

[jay R]

Good morning everyone,

A quick question as to how everyone measures snap ring grooves, o ring grooves etc? Internal to be specific, using the CMM

Thank you in advance.

Jay

[cmmguy]

location(depth) or diameter

[jay R]

ahh, good point, Diameter, true position, location etc, lol, pretty much everything!!

[craiger_ny]

Disc probe perhaps?

[cmmguy]

As much as I despise Star probes, that is what I usually use.

[#2#]

Some of the ones I've seen are pretty much impossible to measure on the CMM (too narrow). The ones that aren't, disc or star probes. It is unlikely you will be able to measure groove width with the cmm unless you use a star probe and have a 6-way probe.

Most of the time, I end up making a replica and measuring it on the optical comparitor - not the best but it's all I've got.

[jay R]

Thanks everyone, currently, I use an Indi-cal, gauge pins, depth mic, etc, all of which are fine for measuring but don't give me any data relative to concentricity, true position and such. Time to make a phone call, been wanting a disc stylus anyhow.

Jay

[cmmguy]

Thanks everyone, currently, I use an Indi-cal, gauge pins, depth mic, etc, all of which are fine for measuring but don't give me any data relative to concentricity, true position and such. Time to make a phone call, been wanting a disc stylus anyhow.

Jay

The disc is great for diameter(much better than star probe), but you cant use it for location(axial)

[jay R]

Why is that? I think I understand why I couldn't use it for Z axis location but X and Y?

[craiger_ny]

Location you can do as long as it is in the plane normal to the probe.

[JIM HARRIS]

I use a.7 mm probe with a 5 way knuckle.The probe is perp. to the tp20.grind off the other sides of the knuckle.Move probe into grove take a vector point back probe out rotate probe head 90 deg repeat.It works great for size and location.I can check i.d. groves down to about .400 inch.

[cmmguy]

Why is that? I think I understand why I couldn't use it for Z axis location but X and Y?

Axially?? along the axis... Depth... Z if it is the axis of the bore... I try not to specify an axis because you never know which way the bore is facing and sometimes you're taken so literally here...