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How to print accurate size PCB layout? Having problem on printing process!

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Willen

Well-Known Member
Here is a PCB layout designed by other. PCB has 3 normal ICs, so it need to be accurate in size. I used Adobe Photoshop software to measure size and it is accurate in photoshop. Then I saved it as a JPG picture and I printed it but there was little small size on print-out. Actual size is 7.5cm but printed size is 6.7cm only!
I tried with different resolution 250 and 80 but no difference.
Where is the problem? What may be the reason? Are there any setting on PC or printer to print accurate size? Guide me to print accurate in size please!
 
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Here is a PCB layout designed by other. PCB has 3 normal ICs, so it need to be accurate in size. I used Adobe Photoshop software to measure size and it is accurate in photoshop. Then I saved it as a JPG picture and I printed it but there was little small size on print-out. Actual size is 7.5cm but printed size is 6.7cm only!
I tried with different resolution 250 and 80 but no difference.
Where is the problem? What may be the reason? Are there any setting on PC or printer to print accurate size? Guide me to print accurate in size please!

First of all I don't think photoshop is a recommended software for building PCB Layout. But if you insist maybe there's a print setup there that scales down the original image file so try to find it and disable the scaling. Second, there are many free pcb layout software out there. What I always do is using any PCB Layout software I then print it to a pdf file. I am doing this because it enables me to print it on any computer without using the pcb layout software. I am using Bullzip PDF Printer to create pdf files. Prior to printing, make sure first that you disable the page scaling at the print setup of Adobe reader.

Hope I helped.
 
@willem,
how do you open the jpg for printing? i suppose, It should be printed from adobe itself instead of using other softwares.then you cvan calculate the difference bewtween 6.7 and 7.5 and proportionately increse the scaling factor.
i did try this method. but if we scale lengthwise, it used to create problem in breadth.

As suggested by lloydi, try to save the file as pDF instead of JPG, even from adobe photoshop. Let us see.
Finally lloydi is surely correct that we better use some eda software like EAGLE, ExpressPCB, Ki-cad, etc
 
I strongly suggest to use PCB software as suggested by mvs sarma. there is something for everyone's needs, but...

since you already have done all the work, maybe let;s not just throw it away just yet.
any good program will allow you tp print images of particular scale. you can use IrfanView for example.
Steps should be something like this:

- create image (high res, the higher the better).
- open it in IrfanView
- using mouse select area to be printed and press Ctrl+Y to crop it
- click print to open print dialog (or press Ctrl+P)
- select units (cm/inches at the bottom of dialog)
- under Print Size select Custom and specify dimensions
- choose centered print position (should be default)
- click Print
 
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You may also need to set up your printer's properties to give the correct scale factor.
 
EagleCAD....never had a prob. Although manually aligning a double sided board with QFN details can be a bit tricky. I use 3 or 4 dedicated perimeter vias to generate pinholes on the PCB as registration holes using actual pins b4 taping the prints to the board and doing the iron on toner xfer. HP 1102W baby laser printer.
 
Hi

You might try printing to PDF file and then converting to gerber. It's a pain, but....

1. Print to PDF - Try Nitro PDF (its free and produces excellent quality output)
2. Convert PDF to gerber - GerbView is one but their are many PDFtoGerber programs

Once the file is converted to gerber, you will need to view and verify proper conversion and most likely have to edit the gerber files.
The conversion programs don't do perfect job of identifing objects like Thermal pads, pad types (square/round) etc..

Some PCB programs will allow you to import a PCB image which you can then use to trace over to produce a PCB design.

The best approach is to use a PCB design program that produces gerber output. An excellent free one is DesignSpark PCB.
 
if I remember correct, even EAGLE has a way to make GERBER files.

9 Generating gerber files
9.1 2-layer boards
1. Open the board.
2. Select ALL layers to display
3. File>CAM Processor>File>Open>Job...
4. Choose ‘Dave-gerb274x(2layer).cam’. The layers output have been modified from
Sparkfun’s version.
5. Click OPEN
6. Click PROCESS JOB.
Output files will go into the project folder.
17
Check the output files using Viewplot or similar before transmission.
It should produce exactly 7 files that you need to zip and send to the fab house:
• Top and bottom copper (.GTL, .GBL)
• Top and bottom solder mask (.GTS, .GBS)
• Top and bottom silkscreen (.GTO, .GBO)
• Drill file, 2.4 leading (.TXT)
It will also produce 2 files that you don’t need to send:
• .GTP (top paste)
• .gpi (general board info)
Put the 7 files above into a .ZIP file and upload to BatchPCB.com.
 
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.... Actual size is 7.5cm but printed size is 6.7cm only!
I tried with different resolution 250 and 80 but no difference.
Where is the problem? What may be the reason? Are there any setting on PC or printer to print accurate size? Guide me to print accurate in size please!

Something is "scaling" the size of the bmp before printing, it could be the software you are printing from.

In photoshop you can adjust the number of pixels in your bmp (re-sample or re-size) and you also have a setting for pixels/inch. If you do a bit of math you can set those up and then just print from photoshop and DON'T select "fit to page" or any options that will auto-size the image.

Or you can manually adjust the size up and down and measure the result on the printed paper, after a few tries it should be close enough. It only has to be within a couple of percent for all the pins to line up good enough.
 
@willem

Save yourself some trouble and print the image to PDF
suggested by a couple of posts..

jpg is not the appropriate file format for what your trying
to accomplish. That image format resolution can be influenced
by screen resolution, etc.

Use PDF format...
 
Thank you for all for valuable suggestion!!!
Yes I can print exact size but I cannot print with thick layer of toner for Toner Transfer Method. I used Brother DCP-7055 printer. I adjustment had been done like- toner saving mood OFF, brightness LOW, contrast- LOW (even tried HIGH), highest quality DPI (1200) BUT even I cannot! I used PDF. Eventually I thought that Brother DCP-7055 has been made for toner save.
Tell me anything please!
 
use 600 dpi. dont go beyond that.
Then set for paper thickness, if you use thicker paper.
you can locally manage on some HP laserjet 1007, 1020, 1018 etc printers

once you are in to brother and specific model
only their user manual and printer set up might guide you

imagine a person of pcb hobby with same printer as you have , is a rare combination.
Few more trial and error would land you on optimized print.
 
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i got unsuccess after 15 trial printing on BROTHER DCP-7055. :(
 
it is a big machine with many facilities. perhaps careful study would yield results.
one needs to be patient. i can understand your frustration. Incidentally, though not to discourage you
i goggled and somewhere i found another person comments that it might not work for dark prints for pcb making.....
i cant believe unless have have hands on experience.

if you can share your artwork file
perhaps i can try on my HP laserjet P1007.
 
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can't help you with settings for your printer, but i also have problem understanding your exact issue.
for example, what part you consider unsuccessful:
- you tried to print 15 times and nothing happened (no drivers installed, paper jams, out of toner, ...)
- you tried 15 times and print coverage was light or uneven (printing works but print does not look ok)
- you printed 15 times, print was ok on paper but your toner transfer to PCB was not ok (it was light or inconsistent and needed lot of patching or etching ate through toner)

Toner is plastic and in order for it to work in toner transfer method commonly used to prototype PCBs it needs to melt at the right temperature and stick to copper clad board. Not all toners are equal. Quick google search using your printer name and "pcb toner transfer" returned this link:

https://www.instructables.com/id/Toner-transfer-no-soak-high-quality-double-sided/

one of the replies in that page is that toner transfer may not work on Brother because of used toner. This may be something to investigate. Another post on same page suggests that using same printer laminator produced perfect results first time...

It is hard to offer help when there is not much to go on. why don't you post some pictures of your troublesome prints or etching attempts?
 
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probably
willen has to manage the laminator to lower the temperature to suite the pcb based toner transfer. Too slow pcb movement on the laminator, followed by HIGH temperature of laminator drum makes the toner smear on the copper clad.

For dark print, it is only managing the printer settings. Another issue, is with track thickness. if the tracks are too thin, perhaps he cant expect dark print to have more toner deposition.
 
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I tried with various pcb layout dowloading from internet.But cannot print with dark and thick toner. i think i should have to try with different printer.
 
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