PCP Prototyping

I'm looking into making one-off PCBs at home (I'm in the UK). My interest is
in making small boards (say, up to 2x4") that have DIL chips on them (op
amps and PICs), along with the usual leaded components. SMD (0805 size)
resistors and caps are a possibility. Single-sided to start with, may try
double-sided provided I can get the registration sorted.

I've been looking at Maplin's web site, and the following caught my
attention...

Etch-resist transfer.
Maplin part AB15R, 15ukp for 5 sheets 11x8.5".
Laser print foil pattern on ***, iron onto board, peel away, etch board.
Does it work? How fine a track can it make, given suitable etching
technique? If the unprinted part of a *** is cut off an hasn't been heated
by the iron, can it be put through the printer again and used to make
subsequent boards?

Etching tank.
Maplin part N53BY, 40ukp.
Clear plastic tank in vertical orientation with capacity for pretty large
board (11" high by 8" wide). Looks like it has a thermostatic heater and air
pump as used with fish tanks, with an airstone inside for agitation. It's
not clear from the photo, but I assume the top is open (could make a cover
if needed).

Sodium Persulphate etching powder.
Maplin parts MC49D (1kg) and N06CG (100g).
100g makes 0.5L. They claim it takes about half the time of Ferric Chloride.
Is it any good? Hazards? How long does the solution keep if stored in an
airtight bottle (presumably with some air inside)?


My only misgivings at present concern the etching tank. An aquarium heater
and air bits cost about the same, making the tank essentially free. If it
works, the can't-build-it-for-less factor would make it a cheap and cheerful
introduction However, it's rather large for the board size I envisage, and
the vertical heater means that it must be filled regardless of board size -
meaning about 2.5 litres of etchant in an arguably unstable shape to do even
a 1x1" board. A squat shape, like Maplin part YA38R is much better, but too
pricey at 250ukp.


Comments and suggested alternatives invited. :-)


--
Melodolic Spielberg


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