Scale confusion ... again

Hi guys

I have 4 site plans which Ive pulled together onto a single drawing and using 4 different viewports within my A1 titleblock.

My problem is that despite, for example, the site plan A measuring the same on both the original drawing as well as the "merged" drawing, and the viewports set to the same scale, when I check measurements on the plotted merged drawing the scale is slightly out.

For example a wall measuring 6160mm in MS measures 5900mm on paper. Another measuring 2945mm in MS measures 2800mm.

Im having this problem whether I insert the drawings as Blocks or simply Copy and Paste.

Also, the measurements I do in MS match the dimensions provided.

What am I missing?

Rob

Obviously the scale is correct in model space. If it's wrong on the plan, then the discrepancy must be in the viewport or in the plotter. Does your plotter print everything else properly? Are the units correct in your scale list?

It's strange that it measures an even number of millimeters (or 100mm). Have you tried measuring the distances in paper space, and if you get the same results, have you got Snap Mode activated?

Just a shot in the dark... Change DIMASSOC to 2 and try dimensioning in PS again.

What scale are you using to plot them?

Sorry I was off on Friday and Monday so didnt get to respond.

Ok Im working on a different drawing today and having the same problem so maybe its a Cad setting Ive messed up?

I will refer to this drawing instead as its a single VP and simpler.

In this drawing, a line which measures 85000mm in MS and PS measures exactly 80000mm on a scale rule on a plotted drawing.

CyberAngel - Yes Ive double checked a few measurements in MS and they are correct. Ive also confirmed that the VP is correctly configured.

Tyke - Yeah I have OSNAP on...always

rkent - Im not dimensioning the drawing, Im finding this error when Im double checking the scale of the plotted drawing.

SLW210 - 1:500.

Any other suggestions guys? These are the 2 drawings Im currently working on so its pretty urgent.

"Im finding this error when Im double checking the scale of the plotted drawing."

Tell us what all your plot parameters are or provide a screen shot of the plot dialog box.

Are you selecting 'fit to paper' (and thus screwing your scale) or something similar when plotting?

Are you selecting 'fit to paper' (and thus screwing your scale) or something similar when plotting?

Kind of along the lines I was thinking.

No I learnt my lesson with Fit to paper long ago.

But Ive made some sort of breakthrough.

ReMarks question prompted me to do something. What I do when I plot is I first plot the drawing to PDF as we are forever emailing PDFs around, I usually then plot the PDF. Which is what I was doing when I picked up the above problem.

So Ive just printed directly from Autocad and the scale is correct.

Does anyone know why or should I head off to the pdftutor people?

Heres the screenshot as requested nonetheless, perhaps it gives someone an idea of why my PDF is coming out at a slightly reduced scale?

PDFs and scaling seem to cause a great amount of confusion, aggravation and anxiety. They are a great tool for conveying an overall concept but our reliance on them in place of actual drawing files is something we need to put an end to. The PDF file format was originally established for the sharing of documents between different word processing programs and was not formulated with CAD drafting and design in mind. If you think of a PDF as just a "pretty picture" instead of an accurate representation of your CAD drawing you'll be doing yourself a favor.

Can you give us a screenie of the plot-window in PDF-to-paper too? I think that there is where the culprit is.

I would give you a screenie of how my looks, but I recently upgraded to Adobe Reader X and that is apparently in Swedish...

A contractor here had the same problem, his company sent him PDFs of the drawings and when he plotted the PDFs the scales were off.

First off, if you have the DWG plot that, it is easier. I cannot remember how exactly I fixed it, but I selected center the drawing and changed Plot Area to either Window or Extents.

Never mind all that. ^^^ That was from acad plot.

What paper size have you selected? What plotter are you using?

Hi guys. Im plotting via HP DesignJet 510.

Im getting nervous here as I regularly email PDFs off to contractors. It really speeds things up. Alot of the time we will supply 1 hard copy and 1 set of PDFs which the contractor can plot themselves if necessary. So the risk that they could have 2 sets of the same drawing at different scales is very real.

I have selected A1 sheet size and rotating the drawing on A0 paper. I haven't tested this problem on A0.

Tiger here are screenshots from what I think are the 3 main windows.

I thought it could be because I send the job as a Bitmap but have tried it either way and still no luck.

On the first image, in the middle you have Page Scaling which is now set to Fit to Printable Area - that is where you need to look. Also, below the litte preview is a percent-value that tells you if the plotted product is scaled or not.

When scale is an issue I make sure that the Page Scaling is set to none, then there is no percent-value displayed and the drawing is plotted correctly.

This happens, I think, because of margins. Your paper-plotter has different margins (i.e. needs some) than a PDF-plotter that can basically have no margins at all if you want.

Thanks Wonderwoma ... I mean Tiger. I am bogged down at the moment and will try out your advice only tomorrow it seems.

Will report back.

If all the necessary dimensions are included with the drawing why is it so important to print the PDF to scale? Either you did the drawing correctly and it includes all the necessary information (thus there is no need to scale anything) or you left out important information and you are relying on the contractor to scale objects (not a good practice in so many ways).

While I agree with you ReMark, I still wouldn't want to send off a drawing that is scaled incorrectly. At least not by such a small amount (98%). and not when it is entirely possible to send it to scale. I would rather send a drawing very much off-scale (say 30%) that is obviously wrong than one that is slightly wrong.

Besides that, it's annoying to have a drawing that is slightly off and not know why.

ReMark its not that simple in my line, most of my work is electrical reticulation on site plan drawings. So for example when Im showing a cable from one substation to another, or the distance between streetlight poles, and the contractor wants to measure than length of cable without referring to a cable schedule, he should be able to whip out a scale rule and measure it.

I cant dimension every length of cable as Im sure you will know.