Homebrew PCBs

--- In Homebrew_PCBs@y..., "Larry Edington" <ledington@a...> wrote:
> No, I didn't look at any of the Canon printers. 
> 
> The Lexmark however has an even better solution than changing heads.
> 
> It has a rubber cup the head sits down on when the head is parked 
to prevent drying. I would fill that cup with ammonia
> water and the head didn't clog until I let the ammonia get too low 
to touch the head. The ideal solution there
> would be to fit a tube into that cup and pressure wash the head 
when it was parked. The normal inkjet
> clean before printing cycle flushes out any residual solvent from 
the surface of the head.

I think all inkjet printers have that rubber cup. The holder for HP 
and Canon print heads has the rubber cup.

The only reason I talked about changing heads is so you can use the 
same printer for regular printing, too. Put in heads with regular ink 
and print a test of the pattern, then drop in the etch resist heads 
and print the final.

It also means the printer does not become junk if (when) the heads 
clog. If you can take the heads out, you can soak them in ammonia or 
just replace them easily.

I like the flushing idea. Just two tubes in the rubber cup, one in 
and one out. A couple of CC's pumped through would be enough to fill 
the cup and flush the head. One sheet printed before printing on the 
copper should be enough to flush the ammonia and provide visual 
confirmation that it is flushed.

> Or a sponge wiper could be put in the path of the head so that when 
it moved away from the cup it
> moved across the sponge to wipe any solvent.
> 
> The Lexmark printers are cheap too! Plus the carriage is light 
enough to mount on a Y axis. The only
> remaining problem is to make the Y move the correct distance with 
each step of the existing stepper
> motor. 

I suppose, but they are built cheap, too, with tiny ink carts. Of 
course if it works, it works.

> The wax printer is something that should be investigated. What 
about the dye sublimation printers like
> the Fargo Primera line that used a wax cartridge in 3 colors. Those 
were waterproof as a standard feature.

Those are almost totally immune to banding because they use a full 
width ribbon. I used to have a Fargo Primera Pro, and they make very 
robust printers. Fargo does make some of the CD wax thermal printers 
and ID badge printers. ID badges would be kind of a small size, plus 
I think the IDs are dye sub only. Dye sub is just a dye, has to be 
absorbed by a coating and won't coat anything by itself.

I love this list!

Steve Greenfield