Check nuts with wrong direction.

I'm kinda confused on your question.

So you acquired a pitch gage? (thing that looks like a saw with teeth spacing for each thread pitch) Similar to this, correct? STARRETT, Metric, 51 Leaves, Thread Pitch Gauge Set - 2ZVE2|472 - Grainger

You are using this to figure out your part's threaded pitch, so you can measure the threaded nuts for True Position. (generally I rely on the drawing spec).. And you are concerned with someone machining them with the incorrect handing? IE Print says RH threads and you are concerned that they'd make the part with LH threads? 

So you want a means to verify thread is correct handing?

Can't that simply be a visual check? i mean right hand threads start to dig into bore in a clockwise rotation.  Left hand threads counterclockwise...

Even so, a simple mating part check -a bolt- is also a real no-brainer verification.

If you are concerned about your application of pitch being correct within your routine's code and measurement strategy, simply turn on display of your hits and look at the preview of hits. For right hand threads: is the green line rotating clockwise whilst going down (or counterclockwise whilst going up)?  you're set then.  if not, flip your pitch.

Thank you for you help. Your explanation is very clear and helpful.

Yes, I got one from a gauge technician. And checked those threads when possible, I did found some errors with wrong numbers.

About my concern, I did find one of our programs used different directions for 4 nuts 2 years ago( Which I thought should be same direction).  But through my test today, I think they do not affect TPs, so even something is wrong, it does not matter... 

What diameter probe are you using?  1.5mm pitch at 8.52mm dia seems super coarse.

I'd try taking more hits.  Six hits about a + and - 1.5mm test pitch, (that's a 0.25mm Rise per hit), could ironically still be hitting on the same or -similar- surfaces within that helix.

Try taking a prime number of hits, like 7, 11, or 13 and see what happens to your measured TP result.   That odd hit count would decouple any coincidental hits.

The incorrect pitch angle will surface worse TP for sure with the pitch not being identical to the current number of hits and their identical 60° spacing.

2mm for our 4 machines in 2 plants,  We use 6 hits for those nuts for almost all programs,

I think you are right.  Odd might make a different. I will try tomorrow morning.

Thanks

I would say no big different with odd hits and random direction

I would say no big different with odd hits and random direction

You've got the same coords for the 4 circles, with the following differences.  ALL are CCW now?
CIR3 = 6 hits, -1.5 pitch
CIR4 = 7 hits, +1.5 pitch
CIR5 = 9 hits, -1.5 pitch
CIR6 = 9 hits  +1.5 pitch

9 Hits is also harmonic (40° increments).  I suggested PRIME numbers for good reason.  EX:13 hits is 27.69° polar angle increments about the 360° arc. 

Your results show variation of about 10% of your tolerance range... I mean it is significant, especially if you find a part that consumes up 80-90% of the position tolerance!

Confirm RIGHT hand threads.  Then test CLOCKWISE (CW) with a pitch that knowingly traverses down (depends on your alignment & surface vectors). Based on your coords, it seems that POSITIVE pitch will work for your parts.

respectfully, if your production process enables wrong-handed threads, i would challenge your production management to figure out an engineering control to mitigate this... like locking up the dammm left hand threaded taps!

I looked at the thread and visual verified the thread with cad hits. Cir2 6 hits -1.5 pitch was what I picked in the program.  I agreed with your conclusion.  :), thanks for your help....