topic Re: Question about scaling and measurements, and printing in AutoCAD Forum

Question about scaling and measurements, and printing

patryk5ZXUH — Wed, 14 May 2025 23:25:23 GMT

Hi,

thank you for your time reading this post, I have a quick question someone hopefully can answer, I am an electrician am getting involved in drawings and autocad, sometimes we get drawings as PDF instead of DWG, the drawings are scaled let’s say 1:100 in PDF so I import this using PDF file but when I use the measurement app the measurement is incorrect, am I missing something am setting the plot scale to match the size but I have a feeling like I am doing something wrong.

please can someone maybe send over some instructions how to set out a drawings to be correct for correct measurements when the drawing is scaled?

also when I go to save as pdf and monochrome and using maximum quality. The drawing looks rough and. Not professional like other drawings? Does anyone have any idea why this is happening also?

Re: Question about scaling and measurements, and printing

paullimapa — Thu, 15 May 2025 01:42:45 GMT

could you share one of these pdfs along with the dwg where you've actually imported this pdf into?

Re: Question about scaling and measurements, and printing

paullimapa — Thu, 15 May 2025 06:50:35 GMT

after importing the pdf you can also try the scale command by reference option

https://autocadtips1.com/2011/04/17/scale-objects-with-a-reference/

Re: Question about scaling and measurements, and printing

will_young — Thu, 15 May 2025 09:09:55 GMT

There are 2 types of PDF, raster based and vector based.

Raster based will become grainy when you zoom in because it uses an image like a jpeg.

Vector based uses line geometry so even when you zoom in it will draw the line at the correct thickness and it retains a clear definition.

When you import pdf I find the easiest way is to check the size, this is given as width height and above the command line when you insert. If the numbers are double digits it will be in imperial inches, if in 3 digits it will be in metric (mm).

For example if it's an A3 drawing in metric it will say width 420, if imperial the width will be 16.5.

First scale to your drawing units ie by 25.4 if you need to go from imperial to metric.

Then scale again by the view scale shown on the drawing ie 100 if 1:100.

You can then measure correctly in model space.

The other method is to use the SCALE command and find a reference length on the drawing.

Important to note that PDF conversion is quite inaccurate and should only be used for rough measurements.