Converting the whole drawing from feet to millimeter

[ot_gert]

I am just a beginner in using autocad. How can I convert the whole drawing from feet to millimeters?

[Alan Cullen]

We need more information......

Basically if you measure a known distance and it measures 10 feet, then you want the entire drawing re-scaled so that the known distance measures 3.048 metres..... is that correct ???? (I'm assuming the drawing is in model space).

If this is the case, then type SCALE at the command prompt...select the emtire drawing (make sure all layers are on, unfrozen and unlocked), select the base point, and enter 0.3048....the entire drawing will be re-scaled so any distances you measure will now be in metres.

Always draw in model space at 1 drawing unit equals 1 whatever unit (feet, metres, whatever).

Hope that helps....if not, then get back to us.... :)

ooooops....I just noticed that you want millimetres.....so select the entire drawing and enter 304.8 for the scale factor...

[Cerberus]

or you could type units on the command line and then pick millimeters in the dialogue box that comes up.

[Boro Nut]

If everybody draws 1:1 in model space you would expect everybody’s drawings to import full size wouldn’t you? Unfortunately it’s not that simple.

You have to remember AutoCAD draws entities in dimensionless units, not millimetres or feet etc. To AutoCAD it's just ‘units’. When you define your preferred units as millimetres or feet, you're just telling AutoCAD how to render your dimensions and text etc.

So when someone with their preferred units set to feet draws two lines 10 feet apart, they’re actually just 10 units apart. When someone else who has their units set to millimetres opens the drawing, the lines appear 10 millimetres apart. In reality (virtual reality surely – Ed) they’re still just 10 ‘units’ apart.

To correct this you need to scale the whole model up or down by the appropriate factor that will render it full size in the units that you happen to be using. In this particular example, as there are 304.8mm in one foot, you would need to scale up by this factor so that the lines would appear 3048mm (units) apart.

The long term solution to this mess is you need to ask the US when will America finally introduce metrication? The answer is 1975 of course, but they never were particularly good at their own history.

Boro Nut