Homebrew PCBs

> AK wrote:
> Which inkjet also has 24+ independent complex
> mechanical systems that have to be maintained?

They have 48 complex mechanincal systems.
Piezo electric effects are mechanical.  And
their main problem is you can't maintain them
easily - you just throw them away. (which isn't
so bad 'cause they are a mass consumer item
that costs 80 cents to make the whole cartridge)

I shall refer you to the 15 page long thread
on amonia/ajax/pumping/syringing to attempt to
maintain ink jets to back up that point

The complexity of the EDM head would not be TOO
much more than an impact dot matrix.  EDM has no
contact and no force on the tool head like
milling.  It is not subject to great force like
an impact dot matrix even.

A spool, a clamp, a voice coil.  dirt would
probably be your biggest enemy.

> It's a relative PITA to keep 2 or 3 of
> something like that working well.  Heck took
> them 15 or 20 years to get inkjets even close
> to right, and even now much of the rightness
> is simply waste half the ink cleaning the
> nozzles..  They're reliable because they're
> simple and fluid instead of mechanical all
> around..

They also HAVE to be reliable.  They have to be
open-loop reliable.

An ink jet printer does not know if a nozzel is
working or not.

There is a difference between individual
component reliability, over all system
reliability and perceived reliabilty (when a
system is not smart enough to cope with small
failures and fail gracefully)

The EDM heads can have closed loop feedback and
tell when they are/have failed.  If it knows a
head has failed the system could accomodate for
that failure (and maybe run at a lower speed)

I have some good books about reliability
I can lend you if you like.


> Make you a deal, get just 6 working well
> for a week then you can tell me how it is
> so much better than an inkjet.. :)  Again,
> I'll expect to hear back about it by at
> least 2012..

I don't think I ever said I wanted to make
one myself :S

But if you want to make a valid challenge -
BET me a bottle of bundy I CAN'T do it by 2012.

Much more convincing that a glib "at least
2012" saying touchè under your breath and
thinking you've made a point.


> AK also wrote:
> Getting 24 wire feeds to the point of not
> having hiccups will take a buttload of over
> engineering

Refer to failing gracefully comment above.

> And it will likely still require an 
> exploding goat here or there too..


We can only hope and pray :D
(preps the goats and shivers in anticipation)