dimension decimal points/commas

[ctopher]

I do alot of dwgs for military (US & Europe) and the question came up about use of points vs commas. I have always known for inches, use points. For metric use commas. Somewhere I have seen this in writing, but do not remember where. There are plenty of specs that have pics of dwgs with points used everywhere, rarely commas ... unles it is a European dwg. Does anyone know where I can find (IN WRITING)about the use of points/commas? When/where they are used? thank you

 

[btrueblood]

Oy. In the U.S. and UK the standard is to use a period (. aka "full stop"), both for metric and inch units. This is shown throughout ANSI drawing standards. In most of the rest of Europe, the standard is to use a comma for the radix, and I think that the ISO drawing standard specifies this (I don't have a copy of the ISO standard, but the comma convention is followed in ISO 5167 (2003) which I do have a copy of). But, not always when you are talking about their money (examples Germany and Finland).

Like the difference in 3rd angle projections, I can see this one being a good thing to define in a title block, if there is possibility of users from both sides of the pond (or channel?) using it. An example could be 1/10 = 0.1 (or 1/10 = 0,1). Or, if you can confirm that the ISO standard specifies it, just specifying the drawing standard may be sufficient (it is for the ANSI standard).

 

[gearguru]

Why we need to specify it? The dimension numbers are "self-explanatory".
At our plant we work with drawings from both sides of the pond, we never had any problems with commas/periods.

 

[ctopher]

With some military/aerospace customers, it has been brought up. Somewhere there is a spec on it. I know here in the U.S., it's no big deal because at a lot of companies most drafting standards/specs are not followed anyway.

 

[btrueblood]

Um, why specify a drawing standard? So you have a leg to stand on when your vendor screws up and makes the parts wrong. Why specify which decimal system you use? I guess if you don't mind getting your 1.000 inch part delivered as a 1,000 inch part (and having to pay for it), then don't worry about it. I think the decimal standard (American convention) is covered sufficiently by specifying the drawing standard (ANSI 14.5M).

 

[ctopher]

I don't need to specify a standard. I just need to show in writing about when/where points/commas are used. Some customers want commas, others don't care (I don't care either way). I just need to show a spec in writing the proof.

 

[looslib]

Well the standards do cover it if you really understand them. Metric dimensions are not allowed to show trailing zero's to get a tighter tolerance. 1,000 on a metric drawing would be 1mm.

"Wildfires are dangerous, hard to control, and economically catastrophic."
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Ben Loosli
CAD/CAM System Analyst
Ingersoll-Rand

 

[ctopher]

I can read them and understand most of them. I just can't find the wording about points/commas.