well as caustic soda is cheap I just make up about a half inches worth in a lunch box develop and then tip it down an outside drain, I'm not sure what it becomes but I guess that at that point it is still mostly caustic soda, it's cheap to buy anyhow. Providing you get the exposure right and don't heat up the caustic soda too much you will have plenty of time to play with it

Simon

On 03/04/11 01:03, Rushden Rotaract Webmaster wrote:

Yes I reasoned the same as you on the tank sizes and was getting fed up with the cereal box and no bubbler so went the full hog.

You could use photosensitive boards, use caustic soda for developing, people say it is too aggressive but that's no wonder if you heat it, barely warm and you have all the time in the world to develop

I'd really like to lower the number of steps further rather than increasing them. I'd also rather not increase the number and amount of chemicals I need to dispose of, that was one of the reasons I decided to start with Cupric Chloride. I have got some caustic soda for titration, but the quantity I need to use is minimal and occasional.

Direct resist printing onto the stock looks really cool, however it seems a bit too hit and miss at the moment for my liking, depends far too much on pot luck with the type of ink that can be purchased:

http://techref.massmind.org/techref/pcb/etch/directinkjetresist.htm

Cost and space are also a factor, whilst I have to buy the print n' peel (though I have read that glossy paper will do) it takes up almost no space and I can get away with printing with an unmodified laser printer (which I have and managed to pick up for free) that can also be easily used for other things.

Martyn