In message <op.ssntfm02mg0lsf@tu-x2pj5qeyp2u4>
"Stefan Trethan" <
stefan_trethan@...> wrote:
> The LJIII has the fuser unit easily removeable,
You can say that again.. Four screws, then it lifts up and out. Very nice.
Check the continuity between the pins on the lamp connector before you buy
one though - replacing the thermofuse is very difficult, if not impossible.
It's even worse if the fuser lamp's burned out.
> and has a thermistor on it
> as any fuser (still need meter for initial adjustment). There might even
> be a triac on that small board on the side, not sure.
No - there's an optosensor; the triac is in the AC Power Unit (the thing
that takes the mains inlet connector). ISTR there's a 24V drive circuit for
the erase lamps, but that's it.
> I guess you would
> need to get one of the gears out of the printer too, or find some other
> way to drive it. I don't remember if it is easy to modify for thicker
> material.
It isn't too hard. Remove the front paper guide (2 screws) and the flip-down
guide at the back (2 more screws). The silver roller is the heated roller,
the red one is a rubber pressure roller. The big problem is that the fuser
feeds REALLY thick stuff (e.g. PCBs) at an angle of about 30 degrees, which
means the fuser needs mounting at an angle. I'll see if it does the same
thing with 0.8mm laminate in a bit, or if feeding from the back makes any
difference.
I need to glue a bit of the plastic on my fuser back together though - I
slipped and broke one of the mounting arms that holds the AC power connector.
Next job is to gut the AC power module and pray that the triac and
zero-crossing optotriac are intact.
Next job is to find a motor. Something that'll run the fuser so that the
board gets fed in at about 0.1ips.
> I'm running my fuser at 160C.
Exactly the same as the HP recommended temperature then. ISTR the LJ3
increases the fuser temp to 180C when it's working on thick media and the
thermofuse trips at 210C.
Later.
--
Phil. | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
philpem@... | ViewFinder, 10BaseT Ethernet, 2-slice,
http://www.philpem.me.uk/ | 48xCD, ARCINv6c IDE, SCSI
... Live every day like it's your last, because someday you'll be right.