AW: [sdiy] DIY pcbs - how difficult is it, and where to begin? (sorry, it's a bit long - make a cup of tea first)

[Matthias Herrmann]

hi julian,

i'm not quite sure if i posted these links already. they show the process of
etching a pcb using press'n peel blue:

http://www.tonepad.com/photoessay.asp?photoEssayID=10&sequenceNo=1 (use of
press'n peel blue transfer paper)

http://www.tonepad.com/photoessay.asp?photoEssayID=11&sequenceNo=1 (etching
using feric chlorid)

cheers!
matthias herrmann




-----Ursprüngliche Nachricht-----
Von: owner-synth-diy at dropmix.xs4all.nl
[mailto:owner-synth-diy at dropmix.xs4all.nl]Im Auftrag von Steve Lenham
Gesendet: Mittwoch, 11. Januar 2006 13:30
An: Julian
Cc: SDIY list
Betreff: Re: [sdiy] DIY pcbs - how difficult is it, and where to begin?
(sorry, it's a bit long - make a cup of tea first)


Hi Julian,

Only a laser printer or a photocopier will work with this system, because
what is happening when you iron the artwork on is that the laser toner is
melting and sticking to the copper. The blue sheets are specially formulated
to ensure that the toner adheres to the copper better than it does to the
sheet itself, so when you peel the sheet away the toner stays attached to
the copper. The toner then forms the etch resist.

Inkjet ink soaks into the paper and dries - it'll never stick to anything.
It's also water soluble so, even if you got that far, the liquid etchant
would dissolve it. All you can do with an inkjet is produce transparent
artwork which could be used to expose photosensitive board material, but
this requires more chemicals, equipment and operational stages, each of
which introduces new opportunities for error.

Suggestions:

Do any of your friends and family have a laser printer you could use? It's
not like you need it that often.

Alternatively (I hesitate to say this, as I'm really not a fan of the
consumerist society), laser printers are dirt cheap, especially (putting my
environmentalist hat back on) if you buy one secondhand off eBay. You've
already noted that it would be useful for panel artwork too - Rapid have a
nice system for that too! Cost would not be much more than the extra stuff
required for photosensitive board work, the results would be better and,
hell, you could print letters on it as well...

Cheers,

Steve L.

----- Original Message -----
From: "Julian" <julian at 22host24.com>
To: "Steve Lenham" <lenham at clara.co.uk>
Sent: Wednesday, January 11, 2006 1:44 AM
Subject: Re: [sdiy] DIY pcbs - how difficult is it, and where to begin?
(sorry, it's a bit long - make a cup of tea first)


> Hmm...
>
> I see the first flaw - actaully exactly the same issue i had with the
> lasertran pannel transfer stuff:
>
> I only have an inkjet.  And copy shops dont seem to like you putting your
> own paper through their machines (i guess in case it gets melted on or
> somthing)
>
> Photocopying may be easier though - with the lasertran i was looking for
> highrez colour stuff.
>
> You ever tried this transfer with inkjet?  Or know of an inkjet compatible
> alternative?
>
> Cheers, Julian
>
> (time to go to bed)
>
>
>
> ----- Original Message -----
> From: "Steve Lenham" <lenham at clara.co.uk>
> To: "SDIY list" <synth-diy at dropmix.xs4all.nl>
> Sent: Tuesday, January 10, 2006 11:46 PM
> Subject: Re: [sdiy] DIY pcbs - how difficult is it, and where to begin?
> (sorry, it's a bit long - make a cup of tea first)
>
>
>> Hi Julian,
>>
>> Have been meaning to reply to this, esp. as not many others have.
>>
>> I make some of my own boards, both for my own use and as commercial
>> prototypes. Because I don't really enjoy doing so (it's dirty, smelly and
>> time-consuming), I only do it when there is a good reason. That reason is
>> usually that I only need one or two boards, and even the best commercial
>> boardmakers aren't very cost-effective at that volume. Any more (even if
> you
>> might only need the extras in the future) and I'd recommend getting them
>> commercially done. Another good reason might be that you need/want the
>> boards NOW rather than next week (or whatever).
>>
>> I also wouldn't entertain making anything other than single-sided boards.
>> Yes, it is possible to do double-sided at home but you need to work very
>> hard to get it right and, even if you get the layer alignment right,
> you'll
>> miss the plated-through holes terribly.
>>
>> If you're still up for it, the good news is that there is no black art
>> involved and I can recommend a simple system which has consistently
>> delivered me very good results (and everything comes from Rapid). The
> method
>> I use is optimised for speed and cleanliness and might not be the choice
> for
>> higher volumes - but IMHO you shouldn't be DIYing large volumes anyway...
>>
>> 1. Artwork
>>
>> Buy the blue Press-and-Peel sheets (Rapid 34-4450) and laser-print the
>> artwork onto them. Obviously it helps if you own a laser printer -
>> photocopying is also supposed to be possible but I've not tried it. If
>> you
>> have laid the board out yourself, you can print stright from the layout
>> software. Ditto if you have a PDF of someone else's layout. Paper artwork
>> can be scanned in, with the advantage that old magazine plots can be
> cleaned
>> up on the computer before printing. The only thing to watch out for is
>> slight scaling errors in the scanning (do a trial run on paper first),
>> but
>> quite acceptable results are possible - I did the old ETI phaser board
> that
>> way.
>>
>> The printed artwork is then ironed onto bare copper-clad board using a
>> clothes iron. Some people have reported that this is a tricky process but
> I
>> can honestly say that I have never had a problem or an unusable board.
>> The
>> critical thing is preparation of the board material. It needs to be
>> really
>> clean and really smooth. First get rid of any hint of a burr along the
> board
>> edge with a fine file (even a small burr will hold the artwork away from
> the
>> copper and prevent it adhering properly at the edges). I then use fine
> wire
>> wool to scrub off the oxide layer and make the copper really bright, wash
>> the board with a bit of washing-up liquid on some kitchen roll (as you
>> can
>> see I use only the most exotic of materials ;-) , rinse it with tap water
>> and dry it off.
>>
>> For the ironing, just follow the instructions which come with the sheets.
> I
>> did so, with no previous experience, and even my first board turned out
>> fine. They specify a range of times for applying heat - use the longest
> for
>> large boards and reduce it for smaller ones. It is better to iron for
>> slightly too long than too little time - overdoing it just causes the
> toner
>> to blur somewhat, but the board is very likely to still be usable.The
>> heat
>> of my iron just goes from 0 to 5 - I use 4. When done, cool the board
>> with
>> cold water and peel off the backing sheet - the toner of the artwork
> should
>> be stuck to the board.
>>
>> This method is good for quite fine artwork - it has no problems with
> tracks
>> passing between the pins of standard through-hole ICs.
>>
>> 2. Etching
>>
>> Buy the Seno etch-in-a-bag system (Rapid 34-0384). Yes, it's more
> expensive
>> than mixing up your own etchant in a pot but it keeps you as far away
>> from
>> the horrid ferric chloride as possible. You only need to ruin one pair of
>> trousers by getting etchant on them and the financial advantage of making
>> that board yourself will be but a distant memory.
>>
>> Again, just follow the instructions, which pretty much amount to putting
> the
>> board in the bag and swishing it around a bit. You can watch the board
>> through the clear bag and see for yourself when it is fully etched. You
> then
>> take it out through an "airlock" which keeps you separated from the
> etchant
>> as much as possible, and rinse off the board (preferably at the outside
>> tap - there will be a tiny bit of etchant still present).
>>
>> The toner can then be removed from the copper with wirewool.
>>
>> 3. Drilling
>>
>> You need a little handheld electric drill (Minicraft, Dremel, etc. -
>> still
>> all from Rapid) and a small selection of fine bits (0.8mm, 1.0mm and
>> 1.2mm
>> will get you a long way). A drill stand would be great, and saves the odd
>> broken drill, but is by no means essential (I haven't got one yet).
>>
>> Some may hold up their hands in horror, but I only use SRBP (paper) board
>> material for my DIY PCBs because it is SO much easier and quicker to
> drill.
>> It also spares you the foul-smelling and rather unhealthy fibreglass dust
>> which drilling conventional material generates. Even so, it's still nice
> to
>> rig up your vacuum cleaner to suck up the dust as it is created.
>>
>> That's about it! Excluding the drill, you are looking at expenditure of
>> about £30 for the artwork sheets, the Seno etch kit and some board
> material.
>> Why not give it a go? Let me know if you need any more tips.
>>
>> Sorry for the ramble - layout software, layout technique and commercial
>> board manufacturers will have to wait for another day!
>>
>> Cheers,
>>
>> Steve L.
>>
>> ----- Original Message -----
>> From: "Julian" <julian at 22host24.com>
>> To: <synth-diy at dropmix.xs4all.nl>
>> Sent: Thursday, January 05, 2006 1:31 PM
>> Subject: [sdiy] DIY pcbs - how difficult is it, and where to begin?
>>
>>
>> Right, Its something ive wondered about for a long time, but never made a
>> start with, so im wondering -  etching your own board: how much of a
>> black
>> art is it?
>>
>> How many attempts is it likely to take before i get it right (i know
>> thats
>> an open ended question, but, is it like 'wow - he got it to work first
>> time - amazing!' or what?)
>>
>> I have a friend who tried twice in the past, with no success, i suspect
> that
>> they were reasonably carefull, so thats what worries me ; )
>>
>> Is there some fool proof technique?  Im guessing that the variables of
>> temperature, time, and chemical makeup all affect things, so im wondering
> if
>> i can get a specific set of one make of chemicals / boards and just
>> follow
>> the directions to the letter - ie to take out any human skill on my
> behalf.
>>
>> I know some of you make boards all the time, but, as i say, im aware my
>> friend had no success, so it cant be that easy either.
>>
>> Any comments at all would be most appreciated.
>>
>> Again, im in England, so any suggested products need to be available here
>> too.
>>
>>
>> Failing all that, if i want to get a company to do it for me...
>>
>> To go from the schematic to pcb, i need to do the layout in some program
>> (any free and easy suggestions?) and upload the file to a company (i know
>> there have been threads in the past on companies), but, having never used
>> the layout software, im wondering how automated it all is?  Ie. is there
>> stuff i need to *know* about board layout rather then just being careful
>> with inputting data off schematic?  (Will i have decisions to make)
>>
>> Basically, id like to start on this, whichever way, but id really like
> some
>> pointers as to where to begin.
>>
>> Cheers, Julian
>>
>>
>>
>>
>
>
>
>