I am about to define the default unit system that we will use in our CAD system in our company and I want to know if anyone has a particular opinion or experience on which unit system has worked best for you. I know this can be industry specific, but I am after general thoughts here.
Our parts and work is such that mm is perfect for units of length, but mass is the tricky one. In my experience, most of the external information (i.e. materials properties) is presented in kilograms rather than grams, hence the idea of using MMKS rather than MMGS.
Any thoughts on this? Has anyone used one and had to change to the other one?
Well, one size fits all does not work for us. So overall default is set to MMGS, also in Mass/Section Properties, to avoid incorrect units generated by SolidWorks. If needed, separate drawing templates are used to show mass in kilogram.
Yes, one size rarely fits all. Quick question, do you go for MMGS because is the SolidWorks default? What incorrect units are the ones you want to avoid with this?
If the setting for Mass/Section Properties (in Document Properties-Units) are switched to Length in centimetres and Per Unit Volume in centimetres^3, file properties combines number with incorrect units for surface area. SW is working on this since the introduction of this new feature in SW2024. Still not fixed in SW2026.
We go for MMGS because it fits best for 75% of our files.
Being Canadian, we have personalized units. We use imperial measurements but have pounds for our weight for instance. I like pounds personally because I’ve seen subcontractors base their quotations using weight as one of the driving factor.
We Use SolidWorks and we are in the UK so we use the metric system. By default Solidworks gives you either MKS, CGS, or MMGS (for metric system).
The bug that @Frank_Oostendorp mentioned is interesting and something to keep an eye on. We are using MM in length with MM^3 for volume. Not sure if the error is only applicable if you use CM, but I’ll keep and eye for it.
Australian here. MMKS all the way for me. MM of course, … because this is the way.! KG Mostly because almost every time we weld more than 2-or-3 pieces of steel together, it will amount to more than a kg. When total build can weigh upwards of 10,000kg, it seems silly to use grams. My2c.