# Need help on Metric vs English conversion

Six Sigma – iSixSigma Forums Old Forums General Need help on Metric vs English conversion

Viewing 8 posts - 1 through 8 (of 8 total)
• Author
Posts
• #51500

Janney
Participant

Anyone has experience on how to validate the measurement that use different unit. In US we use English unit, but in Asia they use Metric. the supplier in Asia areas are often convert our prints to Metric for production and convert back to English to report the results. I experienced a lot of gage correlation issues because they use Metric gage and not English gage. if there is no option that they can get an English gage, what is the best way to solve the gage correlation issue? there are rounding error and gage variation.
Thanks

0
#178617

Participant

Would you not want to ask (tell) your supplier to use a gage / measurement whose resolution is well below your tolerances?
For instance: If your Widget needs to be 50ft long, +/- 1ft, they should be measuring in centimeters and not meters.  Then the gage variation and conversion rounding on centimeters should be “invisible” to the +/- 1ft tolerance.
Just make sure everyone converts in the right direction.  NASA has a pile of rubble in a crater on Mars as an example if you don’t!

0
#178619

RC
Participant

Oh that brings back memories of making sure you’ve remembered to convert the g constant!

0
#178623

Taylor
Participant

Best way to handle is convert your prints to Metric Tolerance.

0
#178624

Janney
Participant

Then, how about the gage correlations? how can we compare the gages if they use different units?

0
#178630

tcm
Member

Juz take a scrape part , place in to soak in a controlled temp environment for ~ 24 hrs. And measure it several times using the gage in question.
Nxt, send the part over to your supplier 0.o… Have your supplier measure the part in the same kind of environment…. And compare both of the results?

0
#178670

Janney
Participant

Supplier told me that they will use 1/10 of the tolerance as resolution. I don’t think it is correct. but they do not agree. for example, we have spec is ..015-.025in, when they convert to Metric, they use .38-.63 mm. they told me the different is at .(63-.38 )which is .25 and divided by 10, then it is .025, so the resolution of the gage is .01. is that right? I think the resolution of the gage should be.001.

0
#178673

GB
Participant

“Supplier told you..” ???
You should be telling the Supplier to meet your needs as the Customer in your measurement schema.
Barring that, As another poster suggested, you change your measurment schema and dictate the appropriate metric measure.

0
Viewing 8 posts - 1 through 8 (of 8 total)

The forum ‘General’ is closed to new topics and replies.