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Export Scale (by yugami)
Is export scale working properly? I imported into another tool and everything was 1/25.4th of the proper size (I'm working in imperial units)

I've setup export scale factor to 25.4 - but I went into the code and noticed its dividing by the scale not multiplying. I want to say thats wrong.
Wed Dec 16 2015, 10:56:18
(no subject) (by yugami)
I should add, my build environment is currently broke or I would have experimented with it already.
Wed Dec 16 2015, 11:03:07
Please read the manual ... (by Roland Frank)
Please look at the "Reference"-page:

Choose View Dimensions in Inches/Millimeters to change the current display units. This does not change the model; if the user changes from inches to millimeters, then a dimension that was entered as 1.0 is now displayed as 25.40.

So the modelling Basis is mm (metric), all else is cosmetic ...
Fri Dec 18 2015, 02:01:55
(no subject) (by Jonathan Westhues)
Most export file formats use a standard unit (points for PDF, fortieths of a mm for HPGL, etc.), but others (like DXF or STL) are sometimes used with both inch and mm units. By default, those formats use mm. I expected people to sometimes also want to use inches, so I showed the export scale as "1:x", since "1:25.4" is a nice number and "0.03937:1" isn't.

Here, it looks like a sketch was created with View -> Dimensions in Millimeters, but the dimensions are actually inches? In that case, upon export you'd indeed want to multiply by 25.4 instead of dividing, so you'd want a scale of 1:(1/25.4). That's slightly clumsier to enter. It's obviously still possible, though, and that case seems uncommon.
Fri Dec 18 2015, 03:58:19
(no subject) (by yugami)
Dimensions in Inches is active.


I'll Walk you through my example

Take a solvespace model with an overall length of 1.745" and export to STEP.

Import into freecad and measure the length - the result is 0.0687 inches. Multiply that by 25.4 and you get 1.745 (with some small error)

IDA-Step agrees that the overall length of the object is 1.745 Units. The units of the file are mm as specified by the header

#158=(
LENGTH_UNIT()
NAMED_UNIT(*)
SI_UNIT(.MILLI.,.METRE.)
);

So we are converting to the correct number, but not the correct unit.

Specifying Inches in a STEP file is a hack, I would request we just convert the other direction.
Fri Dec 18 2015, 10:35:15
(no subject) (by Jonathan Westhues)
Can you post the .slvs file and STEP file? I don't understand what's going on here.

The units in the generated STEP file should always be mm, regardless of how dimensions are shown within SolveSpace. If FreeCAD interprets the STEP file units as mm, then everything should be good. If FreeCAD interprets as inches, then everything should get scaled bigger, not smaller. So if your export scale factor is 1:1, and your dimensions really have been entered in inches, then I'm not sure what's wrong...
Fri Dec 18 2015, 11:08:16
(no subject) (by Jonathan Westhues)
Or maybe the problem is just the "(1:1=mm, 1:25.4=inch)" comment in the configuration screen? That's true for DXF files, because they don't include units. For other file formats, the scale factor is just a scale factor, and should be left at 1:1 unless scaling is desired.
Fri Dec 18 2015, 11:19:49
(no subject) (by yugami)
That just dawned on me, let me correct that and we should be good to go.
Fri Dec 18 2015, 11:32:51
(no subject) (by Jonathan Westhues)
That comment is confusing, since it's not relevant for most file formats. I could add a separate line for "DXF / G code units", maybe, affecting those formats only and with radio buttons for "inch" and "mm".
Fri Dec 18 2015, 11:42:11
(no subject) (by yugami)
That may help.

I saw it and said "Yup I want inches" way way back when I first started using solvespace. Then saw the view and clicked that too. Haven't thought about either of those since then.

problem solved though, thanks.
Fri Dec 18 2015, 16:21:11
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