Crazy move, almost work.

Hello ppl,

I made a stupid move out of desperation in finding an easier way to transfer a pcb design to a board DIY way. Actually I've been thinkering with it for quite some time. I know it's not a smart thing to do, but that's why I posted my
result here so I could get some feedback.

(WARNING!!! could be long)
Here's what I did,I own an epson 900 photo inkjet printer, it's the type of rinter that has an option to print on cd by way of inserting a tray in the back. Looking at it sparks an idea that I could use it to print on something flat and stiff, I did try to print on a stiff and flat surface once and it did work. I put the idea aside after the test.

I've been using a photo sensitized board to etched a pcb for a couple of eeks now and it was good, but the damn thing is too expensive, especially when I ruin a board, I end up with a regular copper clad. I tried the photocopy ransfer method once with no success, because I have no control on what type of paper is used, and I don't have a laser printer. Now I got this crazy idea about printing directly to the pcb, I tried it and tiny blobs of ink are what I got on the board. I tried it again this time I sanded the board and it got a little better, very little I must say. I did some reasearch and found out the inkjet inks are not waterproof, and it just float on surface without special coating. I found an Indian Ink by Pemco that I bought almost 10 yrs ago, and it says waterproof on the label, actually this type of ink is what I am used to when I make PCB, back in high school in Philippines. I open and emptied a used black cartridge and clean it thoroughly and dried. I hot glued it back together and refill it with the Indian Ink, then I tried it and it clogs the nozzle of the printer( I suspect it's because the ink is old).
I put aside the idea and it's been 2 weeks since I tried it.

Today I was so desperate to make a pcb, and I can't get a lift with my brother's car, and it's unreachable by bus. I have a bunch of copper clad that I can't use because it has no sensitized coating anymore. Thinkering with the idea of direct printing to pcb, I decided to give it one more try. I compare the consistency of inkjet ink and the Indian Ink, the latter is a little more thick,( or viscous?)
I looked for something that could be used to thin the ink, I can't use water,
I needed something that would help the ink to dry fast, I found a nail polished
remover, and mixed it with the ink trying to match the consistency of the inket ink by eye, didn't use any measuring device. I was hesitant to use the mixture to refill the cartridge because the nail polish remover label says it's harmful to clothing and plastic,but then the container is plastic ,so I did it any way, then I fire up the printer, the first try didn't looked good, I'm still getting tiny blobs, but this time it seems to dry faster, I still get the image of the whole circuit tho, some areas are translucent. I noticed during the printing process that the printer squirt translucent liquid on it's first pass of it's nozzle. I think it's the polish remover, not mixing well with the ink. After the printing I was eager to look at it closely and touch it, and it smeared, I was very dissappointed. I let the board dry for a few minutes and looked at it again, It seems that the ink is hardened, even when I scratched it harder, the ink stays. I cleaned the board and tried it again this time I wait for it to dry then I inspect it, the shape of the image is very clear ,but some areas are translucent. I figure the only way I could see if those translucent areas are coated was to etch the board, and so I did. The attach image is the result. I'm no expert in electronics
so my question is, is this board usable aside from those obvious missing pads? I'm talking about the imperfection of the copper itself.

I'm convinced that it works, I just need to figure out the right mixture and chemical, I'm thinking of trying ink used in permanent markers, but I noticed it
dries too fast.

(did I tell you I was desperate :) )

slp_prlzys

I would nearly bet that denatured alcohol would probably be a good thinner for the india ink. I don't think it will attack the plastic either. If it were not for the plastic cartridge I would suggest acetone but that will probably soften the plastic. Let us know if you try the alcohol and if it works.
Mike

just a thought, what about printing several times, drying between applications to get a thicker coat.

neat idea though.

I filtered the India ink with a piece of cotton
cloth, I notice that there's particles in the ink,
I think maybe India ink is a mixture of some
powdery stuff and a liquid, or it's just old.
My printout is a little bit even now, but it's
still not fully covered with black, but the shape is
there, exactly the same as the first one.

I think if I could have the board sanded real fine,
the ink would have a better surface to adhere.

turmite:
I'm gonna buy denatured alcohol tomorrow and
will try that.

jimbo:
It's difficult to get a perfect alignment
if I pass it the second time, I had trouble
doing that with film positive.

I will etch this new board and see what happens.

(jpg compression introduce a bit artifacts on the picture,
but very little)

etched the board and it was less than acceptable:(, I think that because
I'm only using one cartridge only those nozzle are actually squirting ink to the surface, therefore reducing the resolution of the printout. If I could maybe fill all the cartridge with India ink, I could get a better coat. Although I know that I won't be able to get a perfect coverage since it's like halftone, it uses dots. I still am positive that it would work. But right now I can't fill all the cartridge with
black as it would contaminate the other colours for when I use it to print images.

So, I would leave this process for someone to thinker with, unless I could get another cheap printer to use just for pcb.
Admin: Sorry for flooding, just thought I'd share. :)

slp,
here is a good source to bounce homepcb ideas off of:
http://groups.yahoo.com/group/Homebrew_PCBs/ There are methods to use a inkjet printer. Printing on transparencies, and printing on paper then copying it (100% size) via a photocopier. Many business's have photocopiers that cost a few cents a copy. If you use a laser or copier, use a glossy agazine page that is mostly white. The glossier the better. I've had pretty good success via laser and magazine paper.

Phil

I read somewhere on the web that someone was polishing a inkjet image on transparancy with shoe polish to make it darker for the photo method. Might work on a board also if the polish sticks to the ink but not the board.

thanks guys,

I tried the photocopy method, I printed the image
on premium glossy paper and then went to (bureau & gros
staples version in Montreal)to photocopy but since
I don't have control on what type paper
is used, it didn't work, even if I soak the board
for 24 hours.

If not for the price of sensitized board I'd stick to
it, with it I found a good use for a negative scanning attachment
that came with my scanner, I use the attachment as my uv light:)
I'm only having problem sometimes with the mixture of developer.

Been here done that. Best way is laser printing -and the setting that will put more toner- over the support sheet of adhesive labels (the one that is retired and not adhesive) because is so anti-sticking that the toner is super easily transferable to the copper. Try not to bend the sheet when cold to avoid cracks of the traces. Put the toner over the copper, use a hot iron pressing evenly, and with some practice you almost do not need any force to remove the paper, and the resolution is very good.

Hope it helps
/U

If you can rig up a cheapy light table. Once you have printed your image you can use the light table to see problems with the print and either fill them in with ink or scrape the area clean.

Urgundiz
I'll try that, but first I'm gonna
have to ask the shop where I did
my photocopy if I could use my own
paper, or start saving money and see if
I could afford a laser printer.

scottsss,
I thought of that, but it's too much
work especially on those tiny tracks,
there are banding lines, the problem
is the ink does not stay where it
was sprayed, it forms tiny blobs.



thanks.

Why not use one of those etch resistant markers and then just draw or paint the entire PCB in a router? Let it dry and etch it. Stick it back in the router to drill it and you're done.

JB

JB,
thanks for the suggestions, the thing is
I don't have a router yet, but I'm hoping
to make one. :)

Quote:

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Originally Posted by slp_prlzys

Urgundiz
I'll try that, but first I'm gonna
have to ask the shop where I did
my photocopy if I could use my own
paper, or start saving money and see if
I could afford a laser printer.

scottsss,
I thought of that, but it's too much
work especially on those tiny tracks,
there are banding lines, the problem
is the ink does not stay where it
was sprayed, it forms tiny blobs.

thanks.

---

Used laser printer can be had for around $100 if you shop around. The good one are HP LaseJet 4 which is a real workhorse (8 pages per minutes). print in mirror image on an overhead transparency and use hot iron to transfer to the copper surface.

I have been using this method for over 9 years and it has yet to fail and you do not have to hunt around for a photocopy machine.

Best regards from Prevost, Quebec

frenchnew

Quote:

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Originally Posted by slp_prlzys

Admin: Sorry for flooding, just thought I'd share. :)

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Flood away not a problem, we love when people share! :)
:banana:

An additive that works 'reasonably' well is Future floor polish, it's clear, but used with ink from a Stadler Mars [red works best] pen, it makes a readily inspectable final solution.
The main reason the ink 'blobs' is because the board is too clean, I know it may not make sense, but ink will hold better on a rougher surface..
A light spray of sulfuric acid [battery acid] will lightly etch the copper ,and result in better adhesion and a cleaner transfer. Another way is to leave the copper somewheres damp until it gets a white / green surface film, and just alcohol wipe, no scrubbing..