Sometimes we don't need dimensions to the nearest millimeter. We should be able to round off to the nearest 5mm or nearest 10mm or whatever is required.
A draftsperson should NEVER over-ride a dimesnion.
We have people here at my work over-riding dimensions to round them off.
It would also be helpful to round-off to the nearest 5, 0.5, 0.005 etc
Sheetmetal work is rarely measured to anything smaller than 0.5mm as that is the smallest increment on an engineering rule.
Furthermore, 2.5, 0.25 and 0.025 etc are also helpful as some older title blocks and company standards use the accuracy of measurement to define the general tolerance
DIMENSIONS TO THE NEAREST
10mm = ±2mm
5mm = ±0.5mm
1mm = ±0.1mm
0.5mm = ±0.05mm
0.25mm = ±0.001mm
Above might not be a very good example as it was rushed, but it is a demonstration of how is works.
A more simple approach on the programming side might be to expand the "Precision" dropdowns to include "10", "100", "1000" on the topside of "0". Might be able to include "5", "50", or "0.5" and "0.05" to get dimensions to the nearest half.
Why not edit the model dim to be what you want? It seems very dangerous to have a difference between what is displayed on the print and what is modeled in the 3D file.
I don't see the advantage of false dims on the print.
Why not show all dimensions to full nine decimal places?
Do a web search on the term significant figures of a number.
It's the digits that carry meaning contributing to its precision.
In many cases too much accuracy is a waste of time and is unnecessary.
That's why we can choose how many decimal places we want to show.
It all depends on the situation. Is it a precise tolerance engine component or something much less accurate.
It's very common in structural drawings to round off dimensions to the nearest 5mm.
The fabricators are NOT going to measure the steel members to the nearest millimetre.
So it's a waste of time showing it.
Can't the drawing be switched to display in meters/centimeters? Wouldn't rounding remove the significant figure aspect since it's going to maintain all the digits until it hits the 1 column? I agree it's a good idea, but I don't think significant figures is a valid argument for it.
So i see the discussion point and agree with a comment that "It's very common in structural drawings to round off dimensions to the nearest 5mm." So how to round up to nearest 5 mm??
I have been trying this but havent figured it out yet. Any help would be great!
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