--- In
Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@...> wrote:
>
> Steve wrote:
> > --- In Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@> wrote:
> >
> >>Any idiot can see that relying on the vacuum pump to clean the
> >>nozzles is useless if the first nozzle to run freely prevents the
> >>other nozzles from being cleaned!
> >
> > Let's keep it civil.
> >
> > A peristaltic pump with a hose hundreds of times larger diameter than
> > the nozzles... I don't think it's quite that clear cut, if it were
> > then the vacuum pump cleaner would be completely useless.
>
> The surface tension is a constant of the fluid. The force required to
> form a droplet is independant of nozzle diameter. Therefore, the Pascals
> required to form the same surface deflection is proportional to 1/area
> or 1/diameter^2. Increasing the peristaltic pump hose diameter will make
> no difference whatsoever. The vacuum pump is only for taking away the
> fluid and forcing it into that fat dunny-roll inside the printer.
I'm not sure it is forming a droplet. It is possible to push or pull
ink through the nozzles without relying on the formation of droplets.
In any case, putting cleaning fluid in the park pad and letting it sit
for hours or a day seems to be a much more efficient way to unclog
badly clogged nozzles.
Steve Greenfield