Laserjet direct PCB printing ideas

Discussion in 'General Electronics Chat' started by Chris11jed, Mar 20, 2014.

  1. Chris11jed

    Thread Starter New Member

    Dec 15, 2013
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    Hello all,

    Just wanted to see if anyone has ever hacked a laserjet printer so that one could pass a copper clad board into a laserjet and have the printer directly print the circuit design onto the copper clad board?

    At present I have some hit and miss experience with "blue sheet" press 'n' peel method DIY PCB manufacture. I print my designs onto this blue sheet, then with a hot iron transfer the design onto the copper clad board. Then use an etching solution (Ammonium Persulphate and warm water) to finish the job. As I've stated, it is a hit and miss thing. I do double sided designs. The miss comes into play when parts of the transfer haven't transferred. Lining up vias and through-hole holes I can do well enough.

    So with this in mind I'd rather just feed the copper clad board into a hacked laserjet and have it print directly onto the board. Searching the internet has been like searching for evidence of UFOs. There's a little 'good' stuff out there, a lot of claims to fame and all the rest is B.S.

    I use a HP laserjet 1102W printer and would love it if anyone has any ideas about taking it apart, re-constructing it into a working model. The idea i have is having a tray one would place a square copper clad board onto, so that once one side is done all that would have to be done is flip in over and the under-side could then be done with some degree of accuracy.

    So there you go. Any thoughts.....
    Thanks
    Chris
     
  2. bertus

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    Apr 5, 2008
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  3. sirch2

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    Jan 21, 2013
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    I believe that Laser Printers use a static charge on the paper to hold the toner before fusing. This may not work on a conductive material such as copper. just saw Bertus's post and obviously it does work...

    We recently discussed toner transfer in this thread - http://forum.allaboutcircuits.com/showthread.php?t=95562

    I use cheap gloss photo paper and it works well, except for very thin tracks on sparsely populated areas of the board (as you will see in that thread, adding areas of copper ground-plane fixed that issue).

    It may be better to do a bit more experimenting with your toner transfer process (paper type. temperature, pressure, board cleaning, etc).
     
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  4. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    Some people have hacked bubblejets and used them to print ink directly onto the PCB.

    From what I remember reading it is a bit fussy. It may need special ink, or special surface conditioning/preheating of the PCB before printing so the ink adheres well. And needs baking of the ink too, before etching.

    But it is "do-able". :)
     
  5. Chris11jed

    Thread Starter New Member

    Dec 15, 2013
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    Hi sirch2,

    After reading through the posts I'd like to know how you have gotten along with your designs. Some suggested using a laminator, did you ever try it out? My problem seems to be similar to yours. Some tracks stick to copper some don't, as well as blobs of toner not sticking to the copper in ground planes.

    Chris
     
  6. Chris11jed

    Thread Starter New Member

    Dec 15, 2013
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    Hi THE RB,

    I like the idea of using a laserjet more so than inkjet printers. It seems a bit of a task to empty an old black toner cartridge and filling it with etch resistant ink. The laserjet toner has that property of resisting etching, which is mostly why I prefer it. But still thank you for your input.

    Chris
     
  7. bertus

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    Apr 5, 2008
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    Hello,

    I see you are using an 1100 series printer.
    From the MSDS sheet you can see that the softening point is about 100 °C:
    http://www.hp.com/hpinfo/globalciti...ductdata/Countries/us/lj_c4092a_us_eng_v7.pdf

    This means that the toner will ¨melt¨ at about 100 °C.
    A lower temperature will not work, a to high temperature will make it flow.

    As for the toner not sticking evenly on the PCB, there can be some "grease" on it so the toner can not get attached.
    This "grease" can even come from your fingers touching the PCB.
    A good cleaning can help for better results.

    Bertus
     
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  8. Little Ghostman

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    Jan 1, 2014
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    I had a very very old hp ink jet, it was dads first one. and I think one the first on the market, I did get it to print direct onto pcb once with few mods, the ink wasnt very good but you can alter that, then the old win 95 machine that ran it died, and both went to the tip :(. My friends dad is a printer, he thinks if I can get a board into a inkjet printer then he can alter the ink.
    The other thing I thought of was using the CNC machine with a ink head from a printer attached to it, somehow fool the software into thinking its a printer, sorry there I go again :D
     
  9. sirch2

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    Jan 21, 2013
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    I never tried a laminator because basically I solved the problem by reducing the heat, adding more copper and "reflowing" the toner after removing the paper. A couple of other things I have learned over the time I have been doing this are: Don't wet the pcb, use a very fine grade of wet and dry sand paper, 800 grit or finer and sand the board as evenly as possible, but do it dry. After sanding clean with acetone and then polish with a clean paper towel.

    Don't overdo the ironing, all you are aiming for is to melt the toner and get it stick to the copper. When it comes to removing the paper soak it for ages, gently rub the paper to remove a layer of backing and then soak more, keep repeating this process. When I have finished there is still a very thin layer of paper stuck to the toner, when the board is dry the toner looks grey not black because of the attached paper.
     
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  10. Chris11jed

    Thread Starter New Member

    Dec 15, 2013
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    Hi bertus,

    I'll have to see what temperature range my iron has and set it to 100degreeC. Thank you for the MSDS link.

    When I clean the copper board I usually use a fine steel wool and warm water. I'll also use a spray of Isopropyl alcohol (99.8%) to help remove the price tag sticker prior to using the steel wool. From what you have said about "grease" I'll just stick to the Isopropyl alcohol and give the water a miss. And i think wearing some washing up gloves or something like that would be a good idea too.

    Again thanks for the help with my 'traditional' way of making my own boards. I'm still thinking about hacking a laser mono printer, and all this info is useful.

    Chris
     
  11. Chris11jed

    Thread Starter New Member

    Dec 15, 2013
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    Hi Little Ghostman,

    If you get your friends dad to perfect the altered ink please post where people can pick it up from or even better how to make it.:D

    That CNC idea is cool. I was thinking of having a 3D printer print either etch resistant material onto copper clad boards, or print metal onto perspex. I've seen it done in a kickstarter. That would be nice....

    Chris
     
  12. Chris11jed

    Thread Starter New Member

    Dec 15, 2013
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    Hi sirch2

    Thank you for your help. I'm going to take what bertus said about the grease and combine it with what you have mentioned about using and fine grit wet and dry sand paper. My next board will be cleaned of the price tag sticker using the Isopropyl Alcohol, dry with a clean paper towel and then use the wet n dry sand paper. Finally cleaning with the alcohol again and a final drying with a paper towel. All while wearing some gloves. ;)

    That and then setting the iron to a 100°C setting and I should see some results.

    Chris
     
  13. Little Ghostman

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    Jan 1, 2014
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    First I have to get a old printer converted, the ink will depend on the printer, or to be more exact the print head, modern ones have a finer print head. The trouble with ink apparently is everyone forgets that it differs in viscosity depending on application. Making a resist ink is easy (so I am told), the hard bit is knowing what will be using it, too runny and it will run and/or dry before it hits the board, too think and it wont leave the head properly.
    So first job is to find a fairly easy to get and cheap printer, then alter to take boards (that cant be too hard???), then we know the print heads to make the ink for :D.
    I talked with him for ages, ink is really interesting when you get right down in the nitty gritty. Also with modification you could in therory do it the other way, have a blank non copper board and print the traces using a metallic ink (silver or whatever), this apparently would be cheaper for most in the long run.
     
  14. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Good thought but It sounds easier than it is. Something (polymer binder) has to hold the metal (copper) particles to the board since copper powder alone will just fall off of the board like baby powder. As soon as you add a resin binder, the resin encapsulates each copper particle and you end up with insulated islands of copper.

    Also, metal particle surfaces tend to oxidize quickly and resistance increases with that. Everyone tries to make conductive inks out of silver because silver oxide is conductive and works best. Not great but best.

    The shape of the powder can be modified to improve conductivity and lots of things are under development. Something will happen soon and printed electronics are becoming more and more common - depending on your definition of printed electronics.

    By the way, did you hear about the 13 year old nuclear physicist in the UK - fusion in the middle-school classroom?
     
  15. Chris11jed

    Thread Starter New Member

    Dec 15, 2013
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    Hi Little Ghostman

    Never thought that the type of print head would be a factor in the modification, nor the viscosity of the ink. :eek:

    I still think a mono laser printer would be best. But hey we work with what we know and like.

    I've been searching around for various 'straight-through' feed laser printers, cheep is also a thing to look out for. And although a but pricey the Brother HL2270DW has such a function. I'm thinking that if I find one for a better price than retail I'd have a crack at modifying it. As you say how hard could it be to modify the feed mechanism so that a copper clad board would fit through???

    But to give some credit where it's due, your mod's to an inkjet ideas would come up with a) a cheaper printer (inkjets are cheaper) and b) as long as the medium coming through that head hits the board and sticks, all good.;)

    Cheers
    Chris
     
  16. Little Ghostman

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    Jan 1, 2014
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    There are already metalic inks mainly based around silver, they would work fine but there are problems. I have also tried to mod a HP 400 (one the first laser printers), its ok on small boards but as the board gets larger you run into all kinds of problems, I dont know if its the heat is dissipated too fast compared to paper, or the charge gets messed up, or what it is.
    The best way is definitely a CNC with printer print head, but its the most expensive.
    The other idea I had was normal resist ink in a super fine artist's pen (the 0.1 mil ones), mounted on a printer plotter! but they cost too much to play with lol
     
  17. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    I've tried the pen on plotter. The pen on copper is not great, every time the wet pen comes to a dry section of ink to complete a trace, the dry ink redissolves and leaves a weakly filled area. Similar results at 90 degree angles so it is best to use arcs in design.

    As for pen size, I think you mean 0.1 mm are available (4 mil). Te problem with thin pens is that they must draw multiple passes for thicker lines. They make "corn rows" since the ink from the first pass is semi-dry by the time the next wet pass comes and this variation shows up in the etch.
     
  18. Chris11jed

    Thread Starter New Member

    Dec 15, 2013
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    Hi Little Ghostman,

    You wrote:
    The boards I can buy are 150mm x 150mm and I usually only need 100mm x 150mm at most most of the time. Hopefully that size is a 'small' board size?

    Of the little bit I've researched into how laser printers work the image is a charge on the drum and that makes the toner 'stick' to it and then that is released onto the paper, finally the fuser heats up the paper and 'melts' the toner into the paper. Could preheating the copper board first help? Did you have to charge the copper board to aid the toner transfer when the drum rolls over it? And did you do double sided boards? Just wondering if the second run has its' own issues or anything...

    Thanks for your input :cool:

    Chris
     
  19. THE_RB

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    You can't use a laserprinter! The drum is a hard roller that is very sensitive and easily scratched and damaged. It won't work trying to press the drum against a hard inflexible scratchy PCB. And there are other reasons like the toner won't electrostatically fix to a conductive PCB, and even if it did the fuser box won't produce enough heat to cook the toner on a heat conductive copper surface.

    The whole idea is dead on the ground.

    Bubblejet printing direct to copper PCB works. People have proved it. I think one guy was even able to use standard bubblejet ink (yellow).
     
  20. Little Ghostman

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    Jan 1, 2014
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    Hi RB, Some inkjet inks work well. The problem is mainly cost of them, I will mention yellow, there has to be something in the yellow one. The older inkjets seem better and easier to mod.
     
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