Help needed, printing several pcb layouts on one paper.

[Sansodor]

Greetings!

I know this has been addressed before but despite my efforts I could not find a solution to my problem. I found several similar threads,
but not one thorough answer to this dilemma. If someone would be kind enough to help me maybe I could turn this thread into a tutorial
so the solution could be found easily.

Here's what I'm trying to achieve: Printing multiple pcb-layouts on one transfer paper. This SHOULD be an easy task. However, my prints
turn out too small every time.

I'm using GIMP for photo editing and my printer is Lexmark E120 (600dpi)

Here's what I'm doing now:

1. Download a few .pdf files for the PCB layouts (GGG, ROG, etc.)
2. Create a new document with the size of 11 x 8.5 inches, 600dpi (US Letter, the size of my transfer paper)
3. Import the pdf-files as layers, crop and arrange so that I'm using the whole paper. The rulers beside the PCB's confirm that I'm doing okay so far.
4. Check image print size and confirm that it is 11 x 8,5 inches.
5. Print, note this: While in print preview my "Image settings" tab shows that the image size is 7.767 x 10.051 inches, 656.651 dpi. Why is this?

I have also tried to print the original pdf-files as is and the result is still the same. I tried with adobe acrobat, explorer etc. I've tried with all the possible settings
on my printer but just can't get it right!

Please help me, as this is very frustrating. I want to start building already.

Thank you for your time!

Here is a file I created using this method: http://www.sendspace.com/file/seeknb

[Earthscum]

make sure it's printing at 100%, not scaled to fit.

[Sansodor]

Yes, I'm doing this already. Forgot to mention it as it seemed so obvious. Anyone else?

[Kearns892]

The rulers beside the PCB's confirm that I'm doing okay so far.

Could you elaborate on this? Do you mean the rulers in the program or the rulers that are part of the image? I know I had problems using a cropping tool in Windows 7 (snipping tool) because even with a PDF set at 100% size the screen resolution made the image actually a little larger on my screen. When I cropped this the screen size was copied and the image in my photo editing program was no longer to scale. It was an easy fix once i realized the problem; I simply measured the scale next to the PCB and using a little algebra what percent off the PCB was and then cropped from a PDF set to that percent.

You might try that, I got very exact results very quickly, still having trouble with transfer paper though. However, I am confused as why you can't print the original PDF at 100% scale with no scaling on your printer and get correct results.

[Sansodor]

The rulers are a part of the image.
- I.e. the pcb size should be 55 x 35mm.
- I pick the selection tool and select that area.
- GIMP gives me a reading of 55 x 35 mm in the navigation bar.
- This should be correct so far, right?

P.S. I tried all these things with another printer at my work and still the same results..

The only solution I can think of now is to measure the printed irl-size of the pcb and compare it to the value that it should be.
Then scale the original files to be that much bigger and try to print again. Surely there must be another way?

[culturejam]

Set the new file in Gimp to whatever the output resolution of the PCB artwork is. Anything made with the old version of DIYLC is at 200dpi. The new version outputs at 166dpi. A lot of the ROG stuff is 300dpi, as are the layouts from Gauss-Markov.

Either that or resize them all to keep the dimensions the same but have the DPI be uniform.

[newperson]

+1 on making sure that your dpi matches.  One tip is to print off on a plain piece of paper before printing on the pnp.  I always keep a 8-16 pin IC socket next to my printer to check if the printer put out the size I wanted it to.  Just match the socket to the printed paper.  It should fit 100%.

Another issue I have had in the past is a printer can overheat the pnp and stretch the image some.  But I doubt this is happening to your if the printer is changing the dpi and the size. 

When I make a layout in Photoshop, the printer always warns me that some clipping will occur.  This is because I make the layout 8.5 x 11 and most printers will not bleed to the end and wants to fit to size by default.

[clamup1]

hey i use gimp also.

#5 you have to change these settings also. i dont know why when you choose your settings in the main window it dosent change there also. i tried to print some pcb's also and had to change the settings in the print options to get them to print right.

[rustypinto]

I use Inkscape, IMO its much better than Gimp at extracting images from PDFs. Once you have your different PCBs "panelized," definitely do dry runs with regular paper as mentioned above. If its too big or too small at this point, scale it using another PDF printer program ("print to PDF" on macs, CutePDF on many windows machines) until its the correct size for your printer. I've gone through many printers, and i've had to go through this procedure each time.

[Sansodor]

Thank you all for your responses. Today I managed to print some correct size papers, yay! Turns out that my layouts were correct, but for some reason
printing out of gimp and adobe reader didn't work. I succeeded with some alternative pdf-program (I did the printing at my work so can't remember the name atm).
However, didn't get to etching yet because the toner wasn't dark enough! The cartridge was running low so I couldn't get a proper transfer. Sucks!

Anyone out there who can recommend a printer guaranteed to work with pulsar fx system?