Master Test Gauge

[Jack Watts]

I'm wondering if anyone knows of a reasonably-priced master test gauge that will work on a lower-pressure gauge (
Alternatively, if this something that a high-end indy tire shop will have on-hand? I need to check calibration on a couple of gauges. While I can test them for precision, I really would like to get some absolute accuracy numbers on them.

Thanks!

 

[jhellwig]

What is your price range? That will make a huge difference.

.1 psi resolution means nothing without accuracy and .1% accuracy will cost you over $500 on a digital guage and over 2k on an analog one.

Be more concerned about repeatability. If you can get that then it is just a matter of figuring out the offset.

 

[Jack Watts]

What is your price range? That will make a huge difference.

.1 psi resolution means nothing without accuracy and .1% accuracy will cost you over $500 on a digital guage and over 2k on an analog one.

Be more concerned about repeatability. If you can get that then it is just a matter of figuring out the offset.

At little as possible, as much as necessary?

I realize that's not an answer. The budget is fairly open as it's for professional use and I could recoup some of the costs from folks looking to test their own gauges.

 

[jhellwig]

Dwyer Instruments BDG-01

Digital Press.Gage,0-150PSIG/10 .342bar/1.034mPa/10.545kg/cm2

www.transcat.com

$76 for .5% accuracy at 150 psi.

Sorry that is my price from them. Might be more for someone else.

 

[HankHill]

I worked with a local certification company that did all our scales, air gauges (highly accurate) temperature readers and other certification needed monthly gauge and readout certifications. I brought in my race gauge with a 1 psi resolution. He tested it and it was, from what we could read on my gauge, like .7 psi off.
Just telling a similar story, maybe if you have industry around you check and see if there is a certification company near you? Honestly they may just hook you up if you tell the story why you need the resolution.. Best of luck! You could always send it away but it will cost $$$$$

 

[HankHill]

Dwyer Instruments BDG-01

Digital Press.Gage,0-150PSIG/10 .342bar/1.034mPa/10.545kg/cm2

www.transcat.com

$76 for .5% accuracy at 150 psi.

Sorry that is my price from them. Might be more for someone else.

Yeah, thats worth it if the accuracy is good down to Lower PSI's like you need. I would keep at least two of these in stock at work. One to test, one to verify test results. I worked in an atmosphere where our gauges were verified almost every week. Worst job ever.

 

[Owen Lucas]

Why the need for such high precision?

 

[HankHill]

Why the need for such high precision?

Our need at work, for such high precision pressure control was for experimental process, to quantify the absolute exact value for the process. It, by business desire, also needed to be verified at least every month, or every xx runs. The process we were running had drastically different results when the pressure was changed by even as little as 1 psi. Repeating experiments, developing procedures and processes, and reporting these values out were our most important values. The verification on our equipment was company standard and cheap insurance against bad data that would have made huge value mistakes.

I can say the process was used on a nickel superalloy parts to improve its properties drastically.

 

[Owen Lucas]

Our need at work, for such high precision pressure control was for experimental process, to quantify the absolute exact value for the process. It, by business desire, also needed to be verified at least every month, or every xx runs. The process we were running had drastically different results when the pressure was changed by even as little as 1 psi. Repeating experiments, developing procedures and processes, and reporting these values out were our most important values. The verification on our equipment was company standard and cheap insurance against bad data that would have made huge value mistakes.

I can say the process was used on a nickel superalloy parts to improve its properties drastically.

Ah science! Very interesting.

 

[Jack Watts]

Thanks for the responses. I have access to a high quality Crystal set-up..but in Taiwan.. I may explore some local options to have my gauges checked, though the Dwyer posted looks like it should be an inexpensive option with reasonable resolution.

The reason I need the higher resolution is that I'm consulting with a number of athletes using these: https://www.sram.com/en/quarq/models/wh-trwz-a1

The device is very precise. Unfortunately though, I have some questions on absolute accuracy--and since pressure is been charted across difference devices, I really need some idea of the absolute readings. My own test gauges are also very precise, but I have no idea of the real accuracy. Ultimately, for a high-level Enduro racer, 1.5 PSI can be the difference between a broken wheel or a broken collarbone... So, I'm trying to ensure consistent setups.

 

[Traction]

It always bothered me enough, many years ago now I bought a $300 digital Intercomp gauge that reads to .1 psi. I just occasionally use it to test my go-to analog dial pressure gauge that has always been spot-on. Whenever I check someone else's gauge I very seldom find one that is right.

 

[HankHill]

Thanks for the responses. I have access to a high quality Crystal set-up..but in Taiwan.. I may explore some local options to have my gauges checked, though the Dwyer posted looks like it should be an inexpensive option with reasonable resolution.

The reason I need the higher resolution is that I'm consulting with a number of athletes using these: https://www.sram.com/en/quarq/models/wh-trwz-a1

The device is very precise. Unfortunately though, I have some questions on absolute accuracy--and since pressure is been charted across difference devices, I really need some idea of the absolute readings. My own test gauges are also very precise, but I have no idea of the real accuracy. Ultimately, for a high-level Enduro racer, 1.5 PSI can be the difference between a broken wheel or a broken collarbone... So, I'm trying to ensure consistent setups.

OMG I don't even want to get started on Absolute Temperature Value, or absolute accuracy. Its like reading three different facts, and then being told they are all wrong, then told they are right and all the same value.

I worked in a facility that used thermocouples to run temperature values on processes. Working with project leads to get requirements and specs for processes was like getting kicked in the stomach. They wanted your input on the highest resolution, most accuracy ability, and best value retaining thermocouples.
I would spec out the best, I thought and could prove, type of thermocouples that they can make. They would eat up the data, then they would use the reported resolution of the thermocouples, and flow the tolerance values down to the next sensor, which had its own resolution and tolerance values. They wanted a tolerance range of xx-xx over the entire sensor values in the entire process. They also would not take that a NIST certified TC was compared to a value that has an acceptable degree tolerance of -3,+3*. So when something was NIST certified, they thought it was the absolute value of a temperature. I spent over an hour trying to explain to a leader that the exact value of the readings were not in fact absolute, and that they had tolerances to them that were different values, depending on the temperature reading amount. Meaning the higher the temperature reading from the TC, the larger the % of acceptable uncertainty was allowed. No matter how I presented it, I always wound up talking to the lead over and over again. They just loved NIST certified values. Loved em!

 

[nomas]

If it's for work , find a testing company locally that will certify all of your instruments .