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Subject: [Homebrew_PCBs] spray etcher page

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2005-09-07

A page about a hombrew spray etcher was brought to my attention.
Note that i do not intend to attempt one again any time soon, but it
surely is highly interesting.

<http://www.modelbouw.gompy.net/etsbak/etsbak.htm>

Thanks Simon for pointing the page out to me, and also for providing a
translation which i am allowed to use (see below).




Translation based on Simons, added to and edited by me:

Klik op de foto's om deze te vergroten.
Click the pictures to enlarge.

Dopje boveaan de sproeipijp met lasdraadje voor bevestiging aan
ventielslang
Cap on the spraypipe with welding rod for attaching a hose.

Sproeipijp gemaakt van 3/4 " PVC-buis met iedere 5 mm een gaat van 1 1/5
mm
spraypipe made of 3/4" PVC tube with a 1.5mm hole every 5mm

Motorhuis PVC-pijp 32 mm met dop
motor housing 32mm PVC pipe and cap

Motor in huis
motor in housing

Ventielslang welke aan de sproeipijp komt vastlijmen met seconde lijm
aan as
Hose (valve hose?, see pic, rubber..) which is attached to spraypipe,
glue with cyano glue.

Stukje PVC in dopje van sproeibuis
piece of PVC (welding rod) in cap of spraypipe

Sproeibuis aan motor met ventielslang
spraypipe attached to motor with hose

Nogmaals
again

Iets dichterbij maar wat onscherp
closeup but a bit blurry

Sproeipijp hangend onder de deksel in dop 32 mm waarvan deel is
uitgevijld.
spraypipe hanging under the lid in cap (32mm) of which it fills
partially. (i reckon it means there's some space)

Deksel open
lid open

We draaien het nog koude draadje rond de pijp
winding the welding rod 'round the pipe

Vervolgens gaan we het verwarmen met de verfstripper
afterwards it is heated with the hot air gun

Even laten afkoelen
letting it cool

Draadje is nu spiraaltje geworden
welding rod has now become a spiral

Van dichtbij
closeup

Spiraal in pijp draaien !! niet drukken
turn spiral into pipe, don't compress it!!

Afknippen op ~4 mm zodat het uitsteekt
cut it leaving 4mm protruding

Spiraal zit nu in de pijp
spiral is now in the pipe

Hieronder nog wat foto's van de complete etsbak
Here some pictures of the complete etcher



Deze bak is met twee motoren uitgevoerd zodat er ook dubbelzijdige printen
in 1x gemaakt kunnen worden.
This etcher has two motors to allow etching doublesided boards in one go.

In het midden wel iets maken zodat de print rechtop blijft staan.
in the middle the PCB is helt upright and in place.



The spiral inside the spray tube is made of 3mm round PVC welding rod.
This spiral can be made by winding the rod around a 8mm copper tube, and
either heating the rod while winding or heating it after it is fully wound
with a hot air gun and letting it cool.

The sprayer tube is suspended in the etcher on a piece of hose of about
5cm length, the idea behind this is that the sprayer tube can swing. If it
were fixed you would see spray patterns on the PCB. When the tube can
swing around, while the patters will still be there they will move around
so have no effect.

-----

In the bottom plate is a hole of about 6 to 8 cm so that the spray-tube
will not swing excesively when the motor turns.
It also serves as stand for the boards.


recommended is that the print is set a little higher, so that it does not
stand in the etching fluid all the time.

Everything is glued with HARD-PVC glue of Bison

-----

The motor can be placed in a section of PVC tube with end cap. Every motor
can be used as long as it fits in the tube.
Do not use any mains voltage motors. This is dangerous with regard to the
etching fluid.

With an adjustable DC power supply the revs of the motor can be adjusted
so that the etching fluid does not spray out of the container.


Well, hope that is of help to someone, please put it in the links section
i'm way too tired to face yahoo.
Sorry about my bad translation but my dutch is from a few months tv
subtitles only....


ST