hi
this link is great!
as i'm from austria it won't be a problem buying.
but i'm also wondering if you may describe the function of the spray tubes more exactly.
it would be very fine if you may describe how the end of the rotating tube is looking, if its simply
open or if there are some propeller blades or so in.
the estimated rotating speed, number of holes, size of holes, arrangement, etc, etc... would all be very
fine.
I really believe this design is genious, shows that not only the americans and englishmen can invent
genious things.
it keeps the whole motor assy out, no shafts, no hoses.. simply very interesting.
i also believe it would not be a very difficult thing to make this myself (it is not so cheap at all i
think)
i also think of using maybe two tubes on one side, to get it more smooth and build it single sided only.
so thanks markus, i believe this is a great page.
but i also think this guy really doesn't want to sell to us or gb.
but they can built this themselves i think...
i really don't want to comment his attitude to selling to us and really hope none of the us guys here
can read the german statement on the linked page because i really want nobody to think all people think
so. i also don't like what's going on in some countries (you know what i mean) on but i think we are
here to discuss homebrew pcbs and not politics.
regards
st
23.04.2003 11:17:36, Markus Zingg <
m.zingg@...> wrote:
>Hi Group
>
>This is my first time post here, so please forgive me in case this is
>already known. However, there is a small german company selling very
>low priced spray etchers which are not that bad. There is a model that
>etches one side, and also one that etches two sides at once. However,
>the single sided model can also be used for double sided PCB's by
>simply turning the PCB once one side is etched. The signle sided one
>goes for ~117 Euro (about the same in USD), the double sided one goes
>for ~178 Euro. I have the single sided one and I'm pretty satisfied
>with the results. The advantage of this etcher is that the device is
>"always" ready, there is no mess with etchant since it's a closed box
>and etching goes fairly quick also (3 minutes per side). The principle
>is simple. There is a rotating tube that delves on the bottom of the
>box into the etchant. Since the tube is having fine holes, the etchant
>is forced out of these holes due to the rotational speed of the tube,
>this results in a fine spray of etchant going over the PCB. Even
>though the device is simple I would find it hard to build the same
>device on my own for the same price. Let me stress that I'm not at all
>related to this firm. I'm simply a happy user of one of their
>products.
>
>Here's the link, search for "Sprühätzer".
>
>http://www.radixgmbh.de
>
>A word of warning though. The guy running this site aparently is
>having a problem with the foreign politics of the US governement. Let
>me stress that because of this I really thought twice to publish this
>link here but then the etcher is simply too good to be ignored.
>
>Markus
>
>>Some ideas I haven't tried:
>>
>>Use a stainless steel stirrer such as is used for making milk shakes.
>>
>>Make some stirrer vanes out of suitable plastic, drive them with small DC
>>motors (so you can adjust speed by adjusting the voltage).
>>
>>Make a centrifugal pump out of plastic. It doesn't have to be terribly
>>efficient, just needs to direct a stream of etchant across the board to be
>>etched.
>>
>>Use an oscillating room fan, or a windshield wiper mechanism to move the
>>board around in the etchant solution.
>>
>>Chemical supply houses have a combination hotplate/stirrer. The stirrer
>>works by having a rotating magnet underneath the beaker, and inside the
>>beaker you put another magnet that is coated with some inert material. You
>>might be able to use a "cow magnet" as the coated magnet. These are fed to
>>cows to attract iron nails and stuff in the cow's digestive system and get
>>them out of the system. (That's no bull :-) I just called a veterinary
>>supply company and they sell a 2-inch coated cow magnet for $2.65.)
>>
>>You might not even need the cow magnet. Since the etchant is conductive, it
>>will try to stay stationary with respect to any magnetic field. So, if you
>>rotate a strong magnet adjacent to the tank, the solution may rotate in the
>>same direction. This is the principle that makes induction motors work.
>>
>>Use a peristaltic pump, such as from scrapped medical equipment.
>>
>>Cheers,
>>- Jan
>>
>>
>>
>>
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>>
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>>
>>
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>>
>
>
>
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