Homebrew PCBs

On Wed, 03 Mar 2004 12:35:38 -0500, Alan King <alan@...> wrote:

> Steve wrote:
>> --- In Homebrew_PCBs@yahoogroups.com, Alan King <alan@n...> wrote:
>>
>>
>>>   The Alps printers are full page, discontinued but plenty of them
>>
>> kicking
>>
>>> around for decal use.
>>
>>
>> Someone already tried. The heads are only designed to print onto paper
>> so they just don't put out enough heat, the copper sucks heat away to
>> quickly.
>
I dunno, but i had not the impression that hp bubblejets actually touch 
the surface.
this is rather impossible because of two plastic "spacers" on the side of 
the nozzles...

so how should they cool the nozzle?

i think the nozzle gets hot any any bad ink hardens.

(also close inspection of a hp head showed that there is only a "gap"
between two electrodes. i could not see a heating element. i think
maybe the ink itself carries the current and heats up.
this would mean also the resistance has to be the same
- but maybe i was seeing it wrong.)

ST