How do I correct this where the dimensions show as true to scale in numerical Meters

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MarkMcC
Junior Member
Posts: 14
Joined: Thu Apr 08, 2021 9:33 am

How do I correct this where the dimensions show as true to scale in numerical Meters

Post by MarkMcC » Thu Apr 29, 2021 4:08 pm

This may seem like a silly question.
I am meant to be using a scale of 1:50.

This was where I started off from needing as a perimeter to work within.
20210429_dimensions convert.png
Original outlay given
20210429_dimensions convert.png (7.53 KiB) Viewed 4282 times
Where I am now below !
With 100 instead of 4M, and 200 instead of 20M
How do I correct this where the dimensions show as true to scale in numerical Meters ?
20210429_qcad-scale-convert.png
current
20210429_qcad-scale-convert.png (77.15 KiB) Viewed 4282 times

Prefs:
20210429_QCAD -prefs.png
Prefs
20210429_QCAD -prefs.png (79.46 KiB) Viewed 4282 times
Units:
20210429_QCAD-Drawing units.png
Units
20210429_QCAD-Drawing units.png (35.68 KiB) Viewed 4282 times

Thanks,


Operating System: Kubuntu 20.10
KDE Plasma Version: 5.19.5
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Version:
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Build Date:
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Qt Version:
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CVH
Premier Member
Posts: 3416
Joined: Wed Sep 27, 2017 4:17 pm

Re: How do I correct this where the dimensions show as true to scale in numerical Meters

Post by CVH » Thu Apr 29, 2021 4:50 pm

Hi,

One can scale the measured value with the Specific Property 'Linear Factor'
in the Property Editor when the dimension(s) is/are in selection.

Odd scaling:
20m = 200 => 1unit = 1dm
4m = 100 => 1unit = 4cm
:roll:
What is drawn is an outer contour of 200m by 100m
and an inner of 120m by 20m :?: What is 6 times 20m and 5 times 4m!?

Usually the advise is to draw in real world measurements, not scaled.
Later, one can present that on paper in any scale. :wink:

Regards,
CVH

MarkMcC
Junior Member
Posts: 14
Joined: Thu Apr 08, 2021 9:33 am

Re: How do I correct this where the dimensions show as true to scale in numerical Meters

Post by MarkMcC » Thu Apr 29, 2021 5:06 pm

Hi,

I did not pick the site measurements or the scale ! I think the 1:50 scale was to make readable on a printer out A3 page.

I there any way I can re-jig this to give correct dimensions in Meters,
and if printed out on an A3, a person could put a scale ruler to it ?

Maybe I started off wrong in the first place, in the settings ?

Any thoughts ?

Thanks.

CVH
Premier Member
Posts: 3416
Joined: Wed Sep 27, 2017 4:17 pm

Re: How do I correct this where the dimensions show as true to scale in numerical Meters

Post by CVH » Fri Apr 30, 2021 3:33 am

Hi,

1:50 usually denotes the paper scale: 1unit on paper is 50units in real world.
That is a uniform scale in both X & Y and is set at paper level.

For technical drawings we use mm as drawing unit.
In landscaping it is common to use cm or m as drawing unit.

Again, as answer to the topic title:
How dimensions are displayed can be set by their linear factor property.
Units can be added in the label property.

Assuming that you are using meters, then 20 by 4 meter is simply 20 by 4 units.
In cm that is 2000 by 400 units, In dm 200 by 40.
And always long and narrow as 20 by 4 m is 5 times longer as it is wide.
On paper, in mm, in 1:50, that would be 400mm by 80mm.
What is indeed about as long as an A3 (95%), but also only 27% of the paper width.
(Probably too long if one consider paper borders.)

200units = 20m (10:1) & 100units = 4m (25:1) :shock:
Using a non-uniform drawing scale is rather odd. (Not that it can't be done.)
It is not very practical as the designer has to scale all items before drawing them.
And with the different scales it is unpractical to work with in real world.

On top, a circle would actually look like an ellipse, a square would appear as a rectangle.
It is getting even harder with angled measurements ...
... A simple ruler won't do it anymore, instead say ruler, calculator and trig math :roll:

How to adapt the existing drawing? ... It should be scaled proper to start with :!:

Sticking to 200/100:
Horizontal dimension linear factor = 0.1; Vertical linear factor = 0.04.
What I can not advise to do.

Sticking to 200/100:
Insert the plants with a non-uniform scale too. :lol:


Regards,
CVH

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