English to Metric Tolerance Issues
English to Metric Tolerance Issues
(OP)
I'm wondering how people are dealing with dual dimensioning and the conversion from english units to metric. I have a tolerance that looks something like this;
INCH = .XX ± 0.01
.XXX ± 0.006
MM = .X ± 0.30
.XX ± 0.15
The problem is that things may pass QC in mm from the supplier but not pass QC interally in english. I know that sounds messy but until we convert over to all metric thats what I'm dealing with. Should I have both english values held to 3 places? I was just wondering what others have done.
Thanks
INCH = .XX ± 0.01
.XXX ± 0.006
MM = .X ± 0.30
.XX ± 0.15
The problem is that things may pass QC in mm from the supplier but not pass QC interally in english. I know that sounds messy but until we convert over to all metric thats what I'm dealing with. Should I have both english values held to 3 places? I was just wondering what others have done.
Thanks





RE: English to Metric Tolerance Issues
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RE: English to Metric Tolerance Issues
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RE: English to Metric Tolerance Issues
RE: English to Metric Tolerance Issues
For example, a 2.00 in dimension would have a size range of 1.99 to 2.01. The way you've converted the tolerance (0.01 in = 0.254 mm rounded to 0.3 mm) the equivalent range is 50.5 to 51.1 mm = 1.98 to 2.01 in. By truncating the converted tolerance to 0.2 mm you end up with 50.6 to 51.0 mm = 1.99 to 2.01 in. Everybody's happy.
RE: English to Metric Tolerance Issues
RE: English to Metric Tolerance Issues