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HP Forum Archive 14

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Help on printing circuit boards
Message #1 Posted by Artur -Brazil on 25 Mar 2005, 8:55 a.m.

Hi! Although not directly linked to HP calculators, but as I see this site is plenty of engineers, I would like to get some help about printing PCBs. I was looking in Ebay there are some HP plotter, like HP 7475, and others X-Y plotters/recorders. First: the small ones, like 7475 could be used to draft printed circuit boards (remember the board can not be bended). Second: is difficulto to use them, if I would like to connect to my HP calculator? Third: what are the X-Y recorders? I could see some specs telling about calibration up to 10Vdc? I have to connect them directly to a power source? If so, why the RS232 connection? Any advice would be greatly appreciated! Artur

      
Re: Help on printing circuit boards
Message #2 Posted by John Limpert on 25 Mar 2005, 11:08 a.m.,
in response to message #1 by Artur -Brazil

Why would you put the printed circuit board in the plotter? All of the printed circuit boards that I have seen made were created by putting the artwork on flexible mylar film, either by hand or with a computer. The mylar film is then used to expose the photoresist coating on the printed circuit board, which is then etched and drilled.

      
Re: Help on printing circuit boards
Message #3 Posted by Eric Smith on 26 Mar 2005, 1:52 a.m.,
in response to message #1 by Artur -Brazil

Someone I know modified an old HP 9872A flatbed plotter to plot resist directly onto copper-clad PCB material. He had to modify the pen holder/lift assembly to account for the thickness of the PCB.

For the non-flatbed plotters, in which the pen is moved on one axis and the paper is moved on the other, this would be difficult if not impossible. They are designed specifically to grip and move paper or similarly thin and lightweight material.

      
Re: Help on printing circuit boards
Message #4 Posted by James on 27 Mar 2005, 5:14 p.m.,
in response to message #1 by Artur -Brazil

Having used a 7475A plotter to make circuit board images on drafting film, I think you will get much better, faster and easier results using a laser printer and the "Toner Transfer" system.

http://www.google.com/search?q=%22toner+transfer%22+pcb

$15 for 10 sheets at Digikey. Part # 182-1003-ND

I haven't actually tried toner transfer, but I would if I were to make homemade boards again.

Good luck!


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