pcb-home etching // home printing?

Salute adesso...

I've read about those hot-iron-printout-transfer-stuff at instructables,
that let me think...

My printer (canon pixma) is able to print CD-Rs and DVDs, so why not print directly on a small sheet of circuitboard, then etch at home?
that would be much easier and there would be no transfer errors
the only thing that's bothering is that if I want to print, I have to name inner and outer circle of the dvd(cd) I'm going to print on.. so that might be a problem...(inner min.17mm outer max.118mm), but if we find a way to skip that
using another printsoftware for example, we can print on a 118mm square and that's enough for both, the powercom and the controller cards...

because I don't have any circuitboards laying around for testing,
I'd like to know what you think about that first...
any suggestions, warnings, hints on printingsoft, anything?
thanks...
I'll go and find me some sheet of aluminium I think I have laying around somewhere for the first try then

'sid

The pixma is an inkjet printer so I think you would need to replace the ink with something thicker that sets.

---

[www.hydraraptor.blogspot.com]

inkjet, true...
what you say is, that I will need something similar but a laserprinter, right?
thanks for the hint, didn't know that

let me see what our officeprinters (some oversized laserprinters) can (cd-printing) next week and if...well we'll see.

'sid

It might be interesting to try using a dye-sublimation printer if you have one of those at work.

~Seth

I've just found an ebayauction that offers very affordable pcb making...
I'd guess I'll quit my "do it at home"-tryouts.

'sid

[www.techniks.com]

The only problem (I think) is that it needs a laser printer, for some reason ink-jet doesn't work (although I may prove them wrong)!

Why all the toner transfer methods use laser printers is because laserjets print plastic that, when remelted with an iron, bonds to the circuit board and acts as a resist. Inkjet ink is either water or oil based, and uses paper's absorbent properties to stay on a sheet. Unfortunately, even if one could get inkjet printing to stick to the copper board,it would not create a usable resist pattern.

I've worked with a variety of PC board construction techniques and in my mind none of them are particularly suitable for hobbyist use. I don't want to bring this chemicals into my home. I don't want to futz with a laser printer (which I don't have) and an iron (which is my GF's). Worse I don't make boards at home often (mostly because it's a pain) so I frequently have to retry a few times before I get an 'acceptable' board. And at the end it's never of the quality of what I would have if I sent it out.

However, having said all of that I wonder of the suitability of the RepRap for making printed circuit boards:

I have to wonder if the Cartesian robot in the RepRap system is capable of precision along the lines required for making a reasonably dense circuit board.

The extruding system centers around low temp melting of materials, this is fundamentally in conflict with all the soldering methods I'm aware of.

I've got access to an etching tank, however the Universal boards are double sided.

Know how do you line both masks up?

Then when you drill the holes do these need plating, how how do you make sure the pins are in contact with both the upper and lower pcb paths?

AcidHell2, you might want to check Luis Freemans work: [www.luis-freeman.com]
He's got a pretty good way of doing this

Joost

one easy method i used to line up the two sides is this:

1st, iron down one side. position doesn't matter too much. this is your reference side.
2nd, drill out the mounting holes, flip the board over. accuracy counts here.
3rd, line the mounting holes up with the print's mounting holes, and secure with a pushpin. use 2-3 pins to get a solid hold.
4th. gently iron on the 2nd side. start in the middle and move out. be careful not to move it when you iron.

you need to drill the holes carefully and accurately, as well as line up the 2nd side carefully. if you do this, your boards should line up pretty well.

Thanks, but how about the two sides making a contact, doesn't sound like any of you have lined to holes, so do the pins of the components insure the top and bottom are connected?

Yes, and you need to add some additional through-vias, so basically solder a vertical connection using a small piece of (discarded) clipping form another component on both sides. That way you connect the two layers (Luis Freeman has got some nice images about this on his site)

Joost

Can you point me in the right direction please, I had a look through his journal. And it explained how to layer them up and everything, but I couldn't see where he's plated it through.

It's no soo much: [luis-freeman.com] and from there on further

Joost

I think the via's that are mentioned are just wires, sometimes component leads themselves that connect top and bottom. Just have to solder both sides then. There is no through plating, so it's an equivalency.

You are correct an Inkjet won't work.
You will need a laser printer, but you can find used Laserjets for almost nothing.

I have used the print and peel blue from techniks that Bozz mentions up thread and it work well. a Heat press like a tee shirt transfer press gives the most reliable results. It is hard to get enough heat and distribute it evenly with an iron.

If you want to make your own boards Check out:
[www.thinktink.com]
There are directions for making any kind of PCB and equipment you might want including plated through holes.
Having said that it any quick turn PCB house will get you quality boards in a few days for a lot less time and money. Getting all of your gerber and drill files right is a royal pain, but you will have to get everything but the drill file right just to make your own PCB.

Best,
Dan

if you're making your own... but if you are making one of our boards, the releases on sourceforge contain gerber and drill files. yay!!

Has anyone seen this design from 2001: [www.buildyouridea.com]

>one easy method i used to line up the two sides is this:

>1st, iron down one side. position doesn't matter too much. this is your reference
>side.
>2nd, drill out the mounting holes, flip the board over. accuracy counts here.
>3rd, line the mounting holes up with the print's mounting holes, and secure with a
>pushpin. use 2-3 pins to get a solid hold.
>4th. gently iron on the 2nd side. start in the middle and move out. be careful not
>to move it when you iron.

>you need to drill the holes carefully and accurately, as well as line up the 2nd
>side carefully. if you do this, your boards should line up pretty well.

I do this pcb making too (laserprinter+iron), but I never arrived to align the 2 sides. And I think with a drill (what you hold in your hand) is impossible to drill exactly vertical holes. So the distance between the holes will not be the same on both sides.

For me I have always an alignement error between 0.5-2mm. So I cant make precises pcbs. (where the lines really thick) So if there is a line between to legs of a microprocessor, it is impossible to fabricate with this method.

So you need either a drill press or a cnc machine (Mcwire?) for making truely vertical holes.

Edited 1 time(s). Last edit at 01/27/2008 07:08AM by khiraly.

Hi khiraly,

i made doublesided etched and milled PCB's at home too.

For aligning the two sides i inserted 4 extra pins in the outer edges, printd/processed one side and drilled only this 4 holes with good accuracy.

Then i drilled this holes in the film of the backside too, turned the PCB and fixed the film with 4 short pins of the same diameter, so it was exactly aligned.

Then i processed the second side and the overall error was mostly down to 0,1 to 0,3 mm.

Here in the image i used an old doublesided PCB from this 'aera' as measure-basis:


This is the secon side - as you can see, a small displacement error is visible, but it was no problem to connect all the pins and insert small via-tubes for connecting the hidden pins under IC-sockets or capacitors ...

Viktor

Seems that one could mount a Dremel into the X-carriage of a Darwin machine with a V-point engraving tool and mill out a circuit board. We do this on a Modela MDX-20 here. It occurs to me that the Darwin frame has similar positional accuracy.
A walk in the park for surface mount designs anyway..
T

But is the Darwin frame stiff enough for light milling? Otherwise it'll skip like crazy...

--Blerik

Only one way to find out.. pity you can't get surface mount stuff in Duplo sizes

yes an inkjet will work for direct printing you have to take the ink cartrige and use Durabright / MISPRO Ink yellow or cyan, heat it so the ink sets and then etch it is far more accurate than laser toner transfer and i have wondered this for some time now if you could do this with a printer that printed on cd and dvd's i am sure that thickness won't be a problem and there should be some kind of sneek around printing technique to print on it wihtout having the holes there. heres a link for more info [techref.massmind.org] if anyone finds out this works email me at eastendgarage@hotmail.com

the Fablab group uses vinyl sign printers to make the over lay on the boards. It would be cool if we could get a cutter for reprap?? Prob would not be to hard..

Bruce

Edited 1 time(s). Last edit at 03/13/2008 01:20PM by Bruce Wattendorf.

Should be able to lay down the existing material AS the etch resist, and peel it off afterwards, assuming it will adhere to the copper plate.

The cheap PCB kit from Radio Shack comes with a felt-tipped marker loaded with acid-resistant waterproof ink. Why couldn't this kind of ink be used in a pen plotter? Wouldn't be hard to make a pen-plotter head for the rep-rap.

People may want to check out
[tech.groups.yahoo.com]

It's a huge unsorted mass of information about pcb fabrication, like

[tech.groups.yahoo.com]
"I've been using
the STAEDTLER permanent Lumocolor "S" 313-2
Its red ink, the pen has a black body with a "S" on the red cap
The ink is a little clear on copper but works with ferric chloride
I buy them at the local newsagent about $3.25 have a scribble in the shop to
check it out first."

----------------------------------
Another gem from that list, as I remember it:

One trick if your art supply store doesn't carry that particular pen:
bring in a blank pcb, and use that as a sample card. (Pick up the black sharpie and write "black sharpie" on the pcb, etc, etc.) Go home, etch the board, and go and buy the pen that worked well as a resist.


-------------------------------

Vinyl Cutter link dump, from 10 minutes with google:
[www.cuttingedgecnc.com]
[www.luberth.com]
[www.cnczone.com]

and
[groups.yahoo.com]
likes to buy drag knives from this company
[www.blades.uk.com]

I should have tried that. Black sharpie doesn't work well with Copper Chloride.