Newsgroups: sci.electronics.misc
Subject: Re: Home made PCBs
References: 
"Periproct"  writes:

> I guess this topic has probably been thrashed out many times here 
> but........
> 
> I'd really like to move away from Veroboard and make my own PCBs.
> 
> I have fallen in love with Marix Multimedia's Technodrill, a sort of mini 
> three axis CNC machine which mills the copper from the board but the price 
> is way out of my league.( 
> http://www.matrixmultimedia.com/articles/Engineering.pdf  page 9)
> 
> Bearing in mind I'll probably only be making the occasional small board I 
> seem to have two choices. Press and Peel and photo resist boards.
> 
> Having read the instructions on the back of a pack of Press and Peel in 
> Maplins (I'm in the UK) it warns of the tracks 'spreading' if you press too 
> hard with the iron so it doesn't sound like a foolproof method. 

This is not a foolproof method, but can work acceptably on some 
cases where circuit boards are not too demanding.

> It also 
> mentions 'topping up' the tracks with a etch resist pen if they don't adhere 
> to the board. I also wonder if you can send a sheet of Press and Peel 
> through a laser printer a second time if you've only used a small portion of 
> the sheet.

I have not tested this myself. I have my doubts on that. 
Most propably running this kind of sheet through the laser 
printer second time is not a good idea. 

> Photo resist sounds good as (I assume) you can print onto easily available 
> overhead projection film 

Photoresists is good method that I have used many times. 
With proper tools it works very well and is a reliable method. 

> but (again I'm assuming) will need another chemical 
> to etch the photoresist from the board before you etch the copper. 

Yes.

The chemical to "etch" the photoresist from the circuit board 
is NaOH. You can get that from chemistry shops. 
Also many "drain pipe opener" chemicals I have seen in my countru 
(I live in Finland) consist mostly of NaOH and water (plus small amount 
some other chemicals). Some people have used those also as 
this photoresist "etch" chemical (suitable mount of water 
and "pipe opener").

> More trips to Maplin only to find they are out of stock, 
> unless you can get the 
> right stuff from the chemist.

You can get NaOH from chemist. It is a very commonly used chemical.

> Any tips from the PCB makers on here?

Check information and links at 
http://www.epanorama.net/links/basics.html#pcb



Here is my older posting on making circuit boards posted 
May 9 2005:

Newsgroups: sci.electronics.misc
Subject: Re: Home made PCB
References: 

"Dan Messenger"  writes:

> Hi,
> I've been making electronic circuits for a while, mostly using Vero 
> Board / Strip Board for final construction. I really wanna move on 
> and start making my own PCBs.

For information on this field take a look at 
http://www.epanorama.net/links/basics.html#pcb

> How expensive is the equipment for this? My boards will probably be 
> no bigger than a few inches square.

This depends on the process you plan to use, how good equipment 
you want etc.. 

Tou can start making simple circuit boards with tools 
that cost less than 100 Euros. But using those you can't 
get best quality, there is lots of hand work and slow process..

For best quality you need much more expensive tools. 

> What is the cheapest way to get me started in this? Can anybody 
> recommend any UK suppliers of equipment? What equipment do I need?

I do not have a recommendation for cheap UK supply. 
You can get all the needed thigns from RS Components 
http://www.rs-components.com/index.html but this is not 
a cheap place to buy many things. But they have 
a very good selection of all kinds of electronics items.

For ideas what tools you need read article links on circuit 
board making at http://www.epanorama.net/links/basics.html#pcb

Tools for normal "photocopy" method are the following:

- photo sensitive circuit board material
- suitable UV light source for transfering image from "film" to
  the cirucit board
- suitable development solution (typically NaOH) and suitable 
  thigns where you can do the development and store chemicals
- suitable etchant (Ferricloride, etc..) and suitable container 
  where you ca do the etching
- small drill with sutiable bits to drill tho holes to circuit board 
  (a suitable drill holder is a good idea to have)

Those are the basic tools. 
And the "film" can be for example a cirucit board layout on 
maghazine page, circuit board image printed to paper, 
printed/photocopied to transparency film etc..

 

-- 
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/