[CurlyBen]

Probably, just about any kind of idea relating to PCB's has been talked about here ...I can't remember any successful stories of conductive printing though. I think somebody tried one of the PCB repair pens, but the resolution wasn't the best.

Sounds like a good idea though, maybe something along the lines of the rapid prototyping setups may be somewhere to start. I would think the conductive ink would need to be printed then "cured" somehow to form a solid track ... good luck

Cheers.

Russell.

Conductive printing is possible (I'm just starting a project on it as part of my third year degree course) by replacing ink cartridges with conductive, insulating, p type and n type polymers. It's not a totally new idea, and it has been done successfully, but there are still lots of issues with it (such as making connections to the 'board' - the substrate is usually paper so obviously you can't solder to it!). I'm not an expert by any means as I have only just started to look into the subject, but my interest was caught by the thread title!

[der_fisherman]

The change for the printer appears to be a great idea and makes it possible maybe for anyone with the right ink, to modify a few other printers that have flat paths for the paper.

I have seen used another method that really works well, provided you have access to a laser printer.

You use photographic glossy paper, on the glossy side for printing to. Your PCB software must be able to print a reversed image (not all do!!).
Experiment and set up the printer darkness control to give as dark a print as possible, but still nice and clean and clear. Run a few copies on normal paper to check first.

Go over the print with a magnifying glass & a modelling knife and scratch off any areas that are wrong, dust marks etc.

Then place the print with the toner side down on a clean PCB (I will cover cleaning after this, very important!) and using a very hot smoothing iron, really get that sucker hot. Iron for at least two minutes without shifting the paper.

The toner will melt again and stick to the clean PCB (if you got it properly clean!).

Let it cool down well.

Place in a bucket of warm water for several hours and without scratching the toner, remove the wet mushy paper with your fingers only. Not your nails! This will leave the toner only on the PCB.

Examine with a magnifying glass, correct any errors by either scraping off toner or using an Edding fine tipped pen, add areas that should not be etched. Edding is also etch resistant.
Add your signature if you feel like it and the date and version if you forgot these!!!

Etch as normal.
--------------------------------------------------------------------------
To clean a PCB correctly, you need to use a Brillo pad or wire wool till it gleams clean all over. Wash/scrub with washing up liquid and distilled water. Dry on paper kitchen towels.
Wipe with Methylated spirits or denatured alcohol without touching it with your fingers (fatal!).
Then proceed as above.

[der_fisherman]

I must admit, when I used to make double sided boards, I never thought of gluing two together, well done. It should work fine and make the finished article twice as stiff and stable as it would be with one!!

If you ever want to make a double sided PCB, it is not as difficult as you might imagine. I used to do them with Eagle and I always only put 3 mounting holes of the usual four needed (but I left a space for the fourth one!!) in an oblong formation. This meant that it would be difficult to put the films on wrongly.
I would make an extra film of one of the sides and use it to mark the three holes. These I would drill the exact size of the hole as it was on the film.

I also put some written information on each side that I needed to be able to read correctly to know that I had the film the right way round.

I would then place the first film on the correct side of the board after removing the black tape on that side only (that protects the UV surface).Carefully lining up the three holes with the mask and making sure that I could read the wording, which was on one usually "Solder Side" and on the other "Component Side".....

Place a thin sheet of glass over the result to keep the film in close contact (this reduces the amount of UV that gets to the PCB. Some clear plastics that allow UV through would be much better.....)
Check that the alignment is still perfect.

Light out with a UV lamp.

Turn over the PCB, remove the black tape and carefully line up the other side on the three holes and light that out with the UV lamp.

Develope the PCB and etch.

It would usually be well within 0.25mm (guesstimation) if done correctly. Even relatively small lands between pads were fine.....

I only made the first board wrong, because I did not have anything readable on each side and I got the sides/films reversed. It was still usable, but the components had to go on the solder side, not a big problem....once I got over the shock....!!

I probably did this for 20 or so different projects...though I did sometimes readjust the board to make very fine lands go via more vias to avoid going between some pads in some areas......tuned up so to say......

Do not have the UV lamp too close, do a longer lighting out rather than having it close, otherwise slight parallax errors start to creep in, away from the middle of the where the lamp is...it depends on how thick the film is to a degree and how fine the tracks and pads are.......

Also, use a test PCB strip (from the same batch) to get the lighting out timing correct. Lamp should be at least 1.5 - 2 ft away from the PCB....I used a strong solar lamp from Phillips originally for sunbathing!!! I am sure that nobdy would use them over their body today!!!! Too strong!!!

Best of luck....

[AlienSteve]

If you want to read about all kinds of methods of making PCBs, head on over to Homebrew_PCBs on ***********. I started the group specifically because the information was fragmented all over different forums and newsgroups as side-topics. This was a way to get all the information in one place, and for the synergy of having a lot of creative people bouncing ideas off of each other.

Toner transfer, direct inkjet resist printing, scratch-n-etch, isolation milling, screenprinting, using a vinyl cutter, photosensitive coatings, printing conductive inks, making your own etchant, soldering using a toaster oven, heat gun, or hotplate, etc. Some topics have side-groups because of the depth of coverage required such as direct inkjet and isolation milling (CNC).

http://tech.groups.yahoo.com/group/Homebrew_PCBs/

From the group description:

Designing, making, etching, soldering, printed circuit boards yourself.

Any method allowed by law and local custom including photo, CAM, toner transfer, direct printing, plotter, laundry pen, silkscreening, toaster oven, paint stripper heat gun, conductive paint or epoxy, storebought or homemade etchant, etc.

Suggestions, recommendations and such to professionals and companies are welcome. If you are posting for your own business, please limit ads to once a month and feel free to post your site in the Links area.
Please be sure to add helpful links to the Links area and use the File area for pictures, PDFs, text, etc.

I only ask that you don't use MS Word DOC or Excel XLS files due to the potential virus risk. Use RTF and comma delimited data instead, feel free to ask if you need help.

A list has been set up just for discussion about converting inkjet printers to print etch resist directly onto PCBs. Hardware, software, inks, baking, etc. are on topic there. Go to Inkjet_PCB_Construction

Questions on general electronics should go to the Electronics_101 list.

[ljcox]

I just stumbled on this thread. I'm usually in the CNC area.

I used to print PCB's more than 10 years ago using a flat bed plotter. I used to use a Roland DXY800. It had the standard HP style plotter pens - the ones with the little wire inside that acts like a valve when the pen pushes down on the paper. You had to use a really fine pen like maybe .3mm. I had to machine a special holder that holds the pen up higher than normal by the thickness of the board.
I used to use a special ink that was meant for plotting on ceramic cups and things. It was bullet proof in the etch. It took quite a while to plot them, much the same as PCB milling does these days but the boards came out excellent. As good as a paper plot of a drawing did in the old days.
I can't use my plotter any more because it was from an era before Windows and I can't find drivers for it for windows.

Sage

Sage,
Have you considered using an interface to convert the data from Windows into the form that is required by your old printer?

It should be possible to do it wuth a PIC and a few components.

The programme would be easy to write if you have details of both protocols.

These days there are PICs that have an internal USB interface.

Len

[martinw]

Dear All,

Can I stand out as a total party pooper?

Get a freeware pcb layout package somewhere, and use people like this..

http://www.pcbtrain.co.uk/

Modified printers, specialist inks and all the rest will not get you PTH, component idents, solder resists and all this. Why suffer, dudes?

Yes, I will not be making myself popular, but anyway, I wish you...

Best wishes,

Martin

[epineh]

Modified printers, specialist inks and all the rest will not get you PTH, component idents, solder resists and all this. Why suffer, dudes?

Hi Martin, I guess it is a matter of horses for courses, for instance I have been working on a microcontroller project for the last few weeks, I decided last night (Friday night) to put the code to the test, printed out a board, soldered it up and started testing today.

I found out I put the icsp header too close to some pinheaders, so I will move things around a little to get it right, reprint it out with a few other minor changes and start soldering up tonight, all in the convenience of my shed, so I am not really suffering as far as I can see.

No board house in the world is going to give me half an hour turnaround, PTH would be nice but for prototyping I can make do just fine, even for fine SMD components, I try keep things no smaller than SOIC packages anyway, not getting any younger you know...

If I had a design that I was doing more than 4 or 5 I would just shop it out, but I rarely need to so the printer wins hands down for cost and convenience.

Cheers.

Russell.

[martinw]

Dear Russell,

Those are all excellent points. Fast turnaround from a board house comes (price-wise) at the near vertical face of a very steep curve!

For more years than I care to admit, I used tapes, UV boxes, sodium hydroxide and tanks of ferric chloride. Then I discovered that photo-plotters and software could do away with the tapes and the scalpels. One small step towards liberation.

Then I discovered board houses. Compared to a DIY system, they are not fast, but in the grand scheme of things, they are cheap, ultimately. No more messing about trying to register the artwork for double layer boards. No more spilled ferric chloride, sodium hydroxide and the rest. No more yellow stains on that pair of jeans, or holes in your sweater. No more hours spent washing all those dishes and surfaces that you spilled evil chemicals on. No more storing the dishes, or illegally pouring the used up stuff down the drain. No more breathing epoxy-glass dust as you drill small holes. No more dreaming of using some hopeless DIY tin plating method that never actually really works.

And you still have no component idents, PTH, plated pads, or solder resists , even if you take that route . It seems a pretty clear choice to me.

Oh yes, one more thing. When that beautiful board comes in through the mail flap, and I find that terrible mistake that I thought I would never make, I just get out that craft knife, the Dewalt drill, and any piece of 10 AWG wire lying around, turn on the plumbers' propane torch, and....fix it. Some things never change, do they??

Best wishes,

Martin

[ftkalcevic]

Dear All,
Modified printers, specialist inks and all the rest will not get you PTH, component idents, solder resists and all this. Why suffer, dudes?

I use the UV exposure method and can have a board developed, etched and drilled in about 30min for about $15. PTH would be nice, but I can work around that.

[epineh]

No more dreaming of using some hopeless DIY tin plating method that never actually really works.

And you still have no component idents, PTH, plated pads, or solder resists , even if you take that route . It seems a pretty clear choice to me.

OK following that kind of logic we should all probably outsource out board manufacturing, while we are at it maybe the design would be better if somebody else did it, hang on a minute, most things I want to make have probably already been made, I should just go on Ebay and buy anything I ever wanted to build, that way it will be done easier and cheaper than I could have possibly done myself.

If you don't know where the components go on a board you design yourself maybe you should stick to golf or something else that doesn't require much thought process.

I never started this thread to tell people what to do, just what I had done, albeit not my original idea but a pretty cool option for those that want to tinker. Toner transfer, UV exposure, are all great options as well as paying somebody else to do the hard work, if you don't like the idea of making your own boards then don't, more power to you, but why get on a direct PCB printing thread and rubbish the method ? I don't particularly care how you get your boards made, good luck to you, but my printer will make my boards for a long time and do it better than any other method as far as I am concerned, this doesn't mean I will tell you to get them made the same way I do, if it doesn't suit you then don't use the method.

And for the record the solder rolled tin plated Allegro A3986 TSSOP package board I made came out just fine, no solder mask but it soldered up nicely, seemed to work perfectly well for me. The chip was a dud but that wasn't the PCB's problem.

Russell.

[martinw]

Dear Russell,

It was never my intention to "rubbish" anybody's work. You can cut dovetails by hand, or use a router and a jig. Different people like different methods, and if they enjoy the one they use, that's fine with me. I guess I just wanted to point out that the board house route need not be hideously expensive, and that, for me, it has advantages. It may well not for others.

I'm glad you had good luck with your plating method...mine always looked OK to begin with and then started to tarnish.

Best wishes,

Martin

[TigerPilot]

Martin, you're missing the point that Russel was making. This thread is about hacking a printer, not about what system of doing PCBs is better. For that there are other threads. This thread is meant to add to your knowledge of how to go about hacking the printer and any post should be about that subject. That's Russel's point.

I guess my post is hijacking this thread too, by definition.

Yoram

[martinw]

Martin, you're missing the point that Russel was making. This thread is about hacking a printer, not about what system of doing PCBs is better. For that there are other threads. This thread is meant to add to your knowledge of how to go about hacking the printer and any post should be about that subject. That's Russel's point.


Yoram

Dear Yoram,

I was not trying to ram the board house route down anyone's throats. I just wished to make the point that if you pursue the method discussed on this thread, there are certain disadvantages. I did agree that there were advantages as well. To me, that does seem a valid reason for posting on a thread, but perhaps not on this one. I did not know that the guy "tending the garden" was so touchy.

Do you know what his problem is with golf? LOL.

Best wishes,

Martin

[epineh]

Do you know what his problem is with golf? LOL.

Best wishes,

Martin

I love golf...if there is enough alcohol involved

[martinw]

Dear Russell,

Namaste.

I admire your bravery. I gave up that game when I was aged ten, having realised how extremely dangerous it is. I managed to chip one of my teeth on a golf club, and I've never played since. Wimp, or what?

Best wishes,

Martin

[smitjs]

Hi There,
Man you are in for a lot of work.
Why not use a printer that can print on a CD?
Sure they are limited, but one can design for smaller boards.
There is also the iron-on method, and the method of using acetone to transfer the laser toner to the board.
Good luck to you
smitjs

[oslop]

I fear not Gil.
The fundamental point is that the laser must have sufficient power, focussed on a tiny spot, to vaporise the metal.
If you had an enormous power available, or could focus down to an incredibly tiny spot, then the power density would raise the temperature sufficient for that to happen.
Unfortunately you also have a good thermal conductor spreading the heat away, so all these combine to make it a bit of a non-starter.
Regards
John

Hi John,

I think this is what you are looking for... check out the video... I would like to see a thread on this myself...

http://www.lpkfusa.com/protomat/pl_s-view.htm

Regards,
Oscar

[fullspeceng]

I called them:
Protolaser S - $140,000
Protolaser U - $220,000

+ shipping

Nice if you can afford it.

_______________________________
www.fullspectrumengineering.com

low cost Mach3 controlled CO2 laser cutters, Inkjet PCB kits, Laser 3D Scanning, Solidworks 3D Mechancial Design, Electrical Engineering Design, overseas CNC manufacturing consulting

Hi John,

I think this is what you are looking for... check out the video... I would like to see a thread on this myself...

http://www.lpkfusa.com/protomat/pl_s-view.htm

Regards,
Oscar

[epineh]

I called them:
Protolaser S - $140,000
Protolaser U - $220,000

+ shipping

Nice if you can afford it.

EEK ! , I think my good 'ol $70.00 C87 will cover my needs for a while yet

Cheers.

Russell.

[greybeard]

I called them:
Protolaser S - $140,000
Protolaser U - $220,000

+ shipping

Nice if you can afford it.

A snip

I like the ingenuity though.
John