Metric to Imperial

Hi all!,

I’m currently trying to get some product manufactured in the US. Being that I have been manufacturing in Australia, all my drawings and documentation are in Metric measurements. When I convert this to Imperial I end up with weird “unclean” measurements. 600mm for example, becomes 1 ft, 11.62 in. Is this an acceptable conversion for manufacture, or should I round up, or even change dimensions to suit america?

Does anyone have any experience in this?

  1. If it’s furniture that is being hand built, possibly problematic.

  2. If it is standard size materials, it might be a problem. You would probably be better off leaving the specs for the stock material in metric and put the processing work in inches.

  3. Otherwise, it shouldn’t be a problem other than in communication. I have the same problems with manufacturing in China. It’s always easier to say, “change the 60mm height to 50mm”. Plus, people think that when you specify 54.39mm that the .39mm is really important rather than the result of rounding from inches.

I would keep everything in metric since that’s how you designed it. Depending on the type of product you’re doing, you might need to alter a dimension here and there as standard material sizes are different in the states. The vendor you choose should be sensitive to that and make recommendations accordingly. In my experience most manufacturing partners here can handle metric no prob and will help to point out how you can make more efficient use of materials.

If you are using Solidworks like us then for the US we display dual dimensions (both metric and imperial) but the imperial measurements are normally shown in fractions (normally to 64th’s).

Don’t assume you have to convert, most manufacturing facilities work in metric anyway in the US, with the above notes exceptions. Also keep in mind the precision of your dimensions, 600 +/- 100 mm is very different than 600 +/- 0.01 mm, and warrants more precision when converting.