Measuring inside groove diameter (Best tool for)

[Newbeeee™]

Where possible on tight work, I'd always go with AHarrisons process.

And PHorn tooling. Finish Turn and groove and groove and turn with the one tool. Chamfers/deburr/blends always spot on too.

For on machine measuring, I don't think you can beat an Interapid

[Roger]

12 minutes ago, Newbeeee™ said:

Where possible on tight work, I'd always go with AHarrisons process.

And PHorn tooling. Finish Turn and groove and groove and turn with the one tool. Chamfers/deburr/blends always spot on too.

For on machine measuring, I don't think you can beat an Interapid

 

"Chamfers/deburr/blends always spot on too".  I never considered this.  Thanks!!

[Mark VIII]

But, you save $263.79!!

[Newbeeee™]

Roger,

Give Martin a bell http://www.western-tooling.co.uk/

He's a used dealer and also deals in old/new stock. I got one off him for around 800 bucks and it was like new.

[jlw™]

3 hours ago, AHarrison1 said:

Hi All,

First time posting here.

Why not finish the bore diameter with the same tool that you are cutting the groove with?

That way the groove diameter becomes tool controlled then all you have to really measure is the bore.

I have done this A LOT.  Sometimes all you have is all you're going to get.  Do the best with what you can.  As long as the machine hits and both ends are good, it "should" be good.  I've had to trust my machine plenty of times.  I've even used the "wrong" tool for the job to use this method.  Sometimes, when we work in shops where we have seemingly unending budgets we forget that so many places make do and get by with what they have.

My second choice would be as suggested with ball mics.  Qualify the OD and do the math.

I just wish equipment was my problem.  We need people with a work ethic.  I used to say "good work ethic" but I'm holding out for any work ethic now.

[Newbeeee™]

The point is, yes you can CMM a part, but you can't do that when the part is in the machine.

So without the right measuring equipment, a solid process that "should" work is the way to go, before the part comes off the machine.

Then to inspection for final verification.

[taperlength]

I have a set of these attachments for calipers.  With some practice, they will measure inside grooves to +/-.001

Just calibrate them on a ring gage or just a micrometer set for the groove diameter.

I set the dial or digital readout to Zero at the nominal diameter.

[SlaveCam]

https://www.mahr.com/en/Services/Production-metrology/Products/Precision-gages/MarCal---Calipers/MarCal---Digital-calipers/MarCal-16-EWV---18-EWR-V---Digital-universal-caliper/MarCal-16-EWR-V---Digital-universal-caliper--IP-67--Data-interface/

I used to use this a lot. The repeability and accuracy was excellent for a caliper, but of course you have to calibrate it to a ring first.

[Charlie Pierson]

Although kind of pricey for a mic, the Starrett ID Groove mic fits your bill and is the simplest tool for the job. IMNSHO

[gcode]

Muller Gages are pretty much an industry standard for this kind of work

You can buy them in all shapes and sizes, from little pistol grip style gages to check .125" ID oring grooves

to 100" + caliper style gages for big VTL parts

 

[Del.]

I thought he was measuring the depth of the grooves. He should be able to find some reasonable point micrometers in different ranges, preferably some deep throat ones.

[Matthew Hajicek - Singularity]

On 9/13/2018 at 4:31 PM, Roger said:

I agree.  Where can you get balls in different sizes?  (I would need one between .118"-.139").  Groove depth/width control what size.  I also have parts with other dimensions.

We're looking into this.  We've not been able to see a price yet.  (I'm the operator/programmer, so I don't have to trust anyone else.) 

On 9/14/2018 at 3:13 AM, Newbeeee™ said:

The point is, yes you can CMM a part, but you can't do that when the part is in the machine.

So without the right measuring equipment, a solid process that "should" work is the way to go, before the part comes off the machine.

Then to inspection for final verification.

Depends on the machine.  Disk on a touch probe could do in machine inspection.

 

[Roger]

Just order one set of metric, one set of Fractional (Fowler brand) from Amazon, for my tool box!  Thanks!!  They should come in handy......

[jlw™]

I have the exact two sets.  I use them mostly for checking BIG threads.

[specv]

We use Mueller gages as general rule, but when we need something economical we have been using these, with a ring gage to use as a master they are very accurate.