• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

DIY pcb's

Status
Not open for further replies.

Chippie

Member
Here's a "How to...." I wrote sometme ago, might help a few people....and if you have any comments feel free.....
 

Attachments

Pilot

New Member
Chip,

A nice easy to follow document for those that have never used uv before - well done.

Nowadays I tend to use Press-n-Peel for my prototypes.

PCB design on screen, send reversed image to Laserjet 6L.

Use a standard clothes iron - non steam - to transfer the toner onto the copper, remove excess then etch as normal.

I've recently used this system for making a dsp - motherboard, processor daughter board and codec daughter board - for a new transceiver I'm building - designed by Peter Rhodes G3XJP and published in RadCom.

As this uses a lot of smd including AD1885JST and ADSP-2181 KS160 chips I was a bit sceptical - even having seen pictures of completed boards using p'n'p.

I tried it and got excellent results now I use it most of the time.

Only one problem with this for most people (within the UK) is the cost - approx £15 for 5 sheets - approx 11 x 8.5 inch per sheet - from RS, CPC and Maplin - when they have it in stock.

I supply this to the members of a large user group with the UK at £1.50 per sheet + p&p.

PM me if you want to try it.
 

bogdanfirst

New Member
well, you got beter ways to do the pcb s, but i use feric clorhide and markers.
noe, the only thing i worry about is transferiing the image of the pcb i have designed on the computer to the board. how?
the way i am using now is look at it and drwa it by hand.
i could use a laser printer, but the ones i have accesible need to bend the paper so no posibility to print directly.
so anybody got any ideas on how to do that better, considering that there are no other ways to do the pcb , just feric clorhide?
 

Chippie

Member
Well thanks for the comments guyz.....


Pilot, I did try P n P some taime ago and gave it up as a bad job.......at £15 a time for 5 sheets.........ouch!!! Nah m8 Ill stick to the way that works for me 8)


regards Chip
 

john1

Active Member
Hi,

yes, i wondered about that too.
I re-read pilots post,
and there seems to be a bit missing after
"send reversed image to Laserjet 6L."

After some thought,
it occurs to me,
that the freshly laser printed sheet,
could be placed face down,
on the blank copper-board,
then ironed with a household iron.

It would appear the intention is to transfer
some of the toner to the circuit board by heating
it up to make it soft.

What intrigues me is that Pilot goes on to say:
"then etch as normal"

************

Now i have no experience of this, but if the
toner can also be used as an 'etch-resist' then
obviously this is the easiest way to do the job
that i've ever heard of.

I will have to try it,
if that is what Pilot means.

If not, hopefully Pilot will explain further.

Regards, John
 

Chippie

Member
John1, yeah thats the way to do it.......

The problem I had was trying to get the P n P to adhere to the board.....no matter how much cleaning, degreasing etc........I couldnt get satisfactory results......I only wanted to make a board 3*2 inches and like I say I used all of the stuff trying to do it........

regards desparate Chip :lol:
 

bogdanfirst

New Member
hey, thanks for the idea with the iron. ill try it.
would it work for a ink jet printer?
i dont think so because it is washable.
 

bogdanfirst

New Member
well, i tried it and it seems to work, i wonder if it works with a page copied at a xerox machine...
o, and by the way, what do i clean the ink with after i make the pcb?
also got a question, how do i get better results, using a highter temperature and shorter time, or lower temperature and longer time?
i mean the temperature of the iron.
 

Chippie

Member
You can take a printed image from a magazine(assuming its shown full size) and run your P n P thru the copier as you would your laser printer...


Clean the etched board with Acetone or something similar...like nail varnish remover 8)
 

bogdanfirst

New Member
ok, thanks for the advice, i mean the problem was not how to get it off, i would figure a way for thant, but know i know. maybe it works with medical alchool? ill try.
another thing about the temperature, the highter the better?
shall i turn the iron on hotter?
 

Pilot

New Member
Always use what suits YOU best.

John1

With p-n-p the etch resist is on the p-n-p. The toner fuses to the copper and p-n-p.

Having worked in a few pcb manufacturers I know the processes they use to clean the boards prior to use and in most cases their way of thinking is... If the preparation is [email protected] the results are [email protected]

With COLD water, wet a soap-impregnated wire-wool pad and use it to polish the copper - reducing the pressure as you go - until it is immaculate. From this point do not touch the copper.

Wash off all traces of soap with COLD water and a clean paint brush.

Dry it with uncoloured kitchen paper.

Then use some more uncoloured kitchen paper to clean it using acetone, isopropyl alcohol or cellulose thinners. Do this in a WELL VENTILATED area.

Heat the iron to approx 140 C - cotton setting - it should just scorch plain 80gsm copier paper.

Use one or more sheets of clean paper between the pnp and the iron you can then continue to follow the manufacturers instructions.

DO NOT use a standard ironing motion or you will smear the trace.

Too much pressure on the iron will smear the trace.

Too little pressure will not transfer the artwork.

The etch resist can be cleaned off with cellulose thinners.

Practise makes perfect.

At least one major pcb manufacturer in North West Uk began switching to a film transfer method 12 months ago. More will follow, especially as it is more environmentally friendly and less chemical storage means reduced costs.

£15 + p&p for 5 sheets is a rip-off
 

Pilot

New Member
Just remembered that somewhere on the web is a site detailing the use ordinary copier paper, a laser printer, iron and a few sheets of newspaper - as a heat buffer - to make pcbs.

That is a nice cheap way of doing the job if the pcb is uncluttered.

See....

http://www.raymondaudio.nl/info/info1/info1.html

and follow the link on that page for a detailed description of that method.

:lol: :lol:
 

kinjalgp

Active Member
Does anyone know what chemical is used to coat the copper clad to make it photo-sensitive?
 

Chippie

Member
kinjalgp said:
Does anyone know what chemical is used to coat the copper clad to make it photo-sensitive?

'Fraid not, but the spray can be purchased.......IMHO its not worth the aggro of coating boards .......I use the pre coated boards.


HTH Chip
 

john1

Active Member
Hi Pilot,

I looked through that web page you posted,
and it had another on it too,
I was most impressed by those pictures
and the very simple manner of doing it.

I did not know that toner could also be
used as etch-resist, but apparently so!

He says he has successfully laid copper
tracks at 10 to the inch, and he says those
seemed clear to him, he says that finer
tracks should be possible.

The next time that i need to make up a
PCB, i will probably try this method.

I usually try to cover most of the board
with etch resist, partly to conserve the
etching solution, and also as sheilding.

Thank you for informing me of this method
of PCB construction.

John
 

kinjalgp

Active Member
I had tried toner method but it did not work with plain printer paper. I then got some glossy sheets which worked well but the next time I went to buy those sheets, I could not get it of the same manufacturer and it did not work. The sheet got stuck to the copper clad very badly and I had no other option than throwing it.
So all those who want to try direct LASER toner method, use good quality glossy paper which should leave the ink as soon as heat is applied.
 

kinjalgp

Active Member
The paper should be greasy like wax coated paper. It should not be rought or it won't leave the ink and will itself get stuck to copper clad.
 

bogdanfirst

New Member
i found some cheap notebooks that have the paper quite like photo paper, it is so fine that you cant write with a pen or a pencil on it at all.
i think that i could use that, cause photo paper is ....expensive.
 
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top