'Unobtanium' gauges???

Reaching out to the group for (hopefully) some guidance and assistance.

I am reviewing a customer RFQ, and noted two items which (IMHO) are unreasonable. These items both deal with the accuracy of measuring instruments. As far as I am aware, there are (currently) no instruments currently available which meet these requirements:

1) Contact measurement (ball-type contact point) of overall height of a feature. Accuracy of the measuring instrument: 0.0005mm

2) Measurement of pressure (and subsequent pressure decay) during a vacuum test. Accuracy of the measuring instrument: 0.001psi

I have done some research and investigation, and am unable to locate ANY instruments which would meet these requirements. I am suggesting to my program manager that we need to 'discuss' these requirements with the customer before signing off on the RFQ. I was instructed/requested/directed to investigate further because 'they wouldn't just make that up'.

If you have any suggestions as to appropriate instruments, please let me know.

Thanks

Ron Rompen said:

I was instructed/requested/directed to investigate further because 'they wouldn't just make that up'.

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It goes hand in hand with “we are the government and we are here to help”.

Knowing absolutely nothing about this business relationship, I would go back to the (potential) customer and ask for their help in finding such resources. If they are serious, they should respect you reaching out for information on such incredibly rare precision instruments.

If for some reason you cannot or do not want to ask the customer, ask NIST. I've needed to contact them a few times and found their scientists to be willing to help industry on such matters.

Ron Rompen said:

2) Measurement of pressure (and subsequent pressure decay) during a vacuum test. Accuracy of the measuring instrument: 0.001psi

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This sounds like a Helium leak test would be more suitable than pressure decay.

Thanks for the responses guys......and particular kudos to Mike S. for suggesting NIST. never even THOUGHT of reaching out to them.

yes, i am already having discussions with the program manager about this.......

Ron Rompen said:

1) Contact measurement (ball-type contact point) of overall height of a feature. Accuracy of the measuring instrument: 0.0005mm

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Would a linear gage work?

Miner said:

Would a linear gage work?

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thats what is being considered, however i am not aware (yet) of any linear gauge which has the required accuracy.

You need an accuracy of 5 μm, correct? These go well below that.

Thanks Miner. The accuracy required is 0.5 microns, but these appear to meet that requirement. I will follow up with the manufacturer.