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Subject: Re: [Homebrew_PCBs] Laser printing - comments and a experiment at the end

From: Stefan Trethan <stefan_trethan@...>
Date: 2004-02-26

> I'll take a look at what that takes, I've always assumed it's just
> higher charging voltage to attract more toner etc but could be done in
> other
> ways. It may just be a set charging voltage then the laser just
> partially
> discharges even the black areas too. Simply upping the high voltage a
> bit may
> be all it takes.
>
> Alan
>
>

Using the same post in multiple groups, are you? (not this one).
clever....


How do i make a copper oxyde layer (not that i say i will do it but just
in case.....)


For darkness:

there is a metal blade in the toner cartridge, it is on the outlet of the
toner compartment and
decides how much toner will get on the magnetic roller with the developer.

I once filled copier toner in the laser printer and found that i needed to
make the
gap much narrower..
If you open the gap too much it is simply to much toner and will fall off
the roller at the other end.
(because it doesn't fit in the "input" gap then.

but you could try to make it as wide as possible.

A schematic of the power supply would be useful to figure out how it
works, but i guess
it can be done with some back engineering. I think a 20 or 30 percent more
will certainly
work without arcing or such.



What i suggest to test:

let the copper stripe through the printer halfway, and then switch off the
power.
now open the cover and take out the drum (with the cartridge).

Now see how much toner is left on the drum after the point of contact, and
how much
is there before. compare to the areas where paper is.

I am strongly interested in this experiment but i don't have copper foil.
(i may try with aluminium)


ST