Or you could add a gear to the platen and use a matching linear gear on the tray.
I have several Epson Stylus 3000 printers, if anyone is close to Lacey, WA USA and wants to experiment with one. But then we should move that discussion over to the inkjet PCB resist group.
Steve Greenfield AE7HD
--- In Homebrew_PCBs@yahoogroups.com, "Leslie Schwartz" <lhs_emf@...> wrote:
>
> Possibly a printer like the old Espon Stylus 3000 which has a tractor feed
> mechanism could produce more accurate direct prints? I would not be able to
> modify and re-engineer the printer to work for this application, but it
> seems you would be able to do it.
>
> -----Original Message-----
> From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
> On Behalf Of eugenio
> Sent: Thursday, June 28, 2012 4:39 AM
> To: Homebrew_PCBs@yahoogroups.com
> Subject: Re: [Homebrew_PCBs] Re: Inconsistent scaling with Samsung ML-2165
>
> Hi guys, in the last two years i've implemented every imaginable way of
> making pcb's at home.
> One of these ways was Mark Lerman's direct laserjet printing, when i
> finished the printer-machine i realized that the printer was inconsistent in
> scaling.
> After studying the inners of the machine i saw that the printer was perfect
> in the execution, the brushless motor was synced perfectly with laser and
> with a perfect constant speed and the clutches were working perfect. The
> guilty is the micro-slips of the pcb with the rollers. It can be seen
> testing that transparencies are more inconsistent than normal paper for
> example.
> The easy solution is to harden the springs of the rollers, and the perfect
> but difficult solution is to make a carrier with the same speed as the
> photosensible roller.
> I was able to direct print multiple times in the same pcb and you wouldn't
> notice, and i had perfect registration in two sides. I used a fpga to
> substitute the sensors stuff of the machine.
> For the curious, Mark Lermans's way didn't fit my needs so i discarded it,
> but for other problems different that consistency, the most important one
> was that toner is not a good resist for plating with 4-5 mils precission.
>
>
>
>
> On 06/28/2012 02:46 AM, godzilera wrote:
> > It's not a question of just adjusting the scaling; the problem is that
> it's inconsistent. Sometimes it would come out too small, sometimes it would
> come out too big...
> >
> > However I have now managed to print at least three perfect copies using
> the HP photo paper by printing my layout at the bottom of the page. This
> seems to confirm that the speed of the paper is only inconsistent at the top
> of the page. I think that is because the roller that pulls the paper out of
> the tray is also responsible for pushing it over the drum, and some slippage
> occurs with the thicker and glossier paper. Once the paper hits the fuser
> though, then there is enough pressure to pull the paper with a constant
> speed.
> >
> > Anyways, my board has been printed and etched, and it looks perfect. In
> the future, I think I will probably cut strips of TTS or photo paper and
> tape it to another sheet to make sure I always print on the bottom of the
> page without wasting a whole sheet.
> >
> > In general, I think the straighter the paper path, the better. With the
> old HP LJ 4 at the office I used to use the manual feed and open up the
> back, so that the paper would not curve up back to the front, but that is
> not possible on this ultra-small Samsung.
> >
> > For now, the little Samsung at $90 works fine as long as I can work around
> its limitations.
> >
> > Thanks,
> >
> > Pete
> >
> >
> > --- In Homebrew_PCBs@yahoogroups.com, DJ Delorie<dj@> wrote:
> >>
> >> When I did TT, my process was to print a "calibration board" and go
> >> through all the steps until just before etching, and measure the pcb
> >> itself to find out what the X and Y scale factors are. Each step
> >> along the way might alter the dimensions somewhat, so it's important
> >> to just check the results you care about.
> >>
> >> gEDA/PCB, btw, has separate X and Y calibration values you can fill
> >> in to adjust printouts, just for toner transfer.
> >>
> >
> >
> >
> > ------------------------------------
> >
> > Be sure to visit the group home and check for new Links, Files, and
> Photos:
> > http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> >
> >
> >
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>