Yes, the motor is only driving the bottom roller. Driving both is nice but not needed. Copper clad goes through fine with only driving the bottom roller.
--- In Homebrew_PCBs@yahoogroups.com, Ryan Fobel <rrfobel@...> wrote:
>
> This looks great. I'm not sure if I'm seeing it right, but it looks to me
> like the motor is only driving the bottom roller. Is that true?
>
> What material are you using for the side plates? It looks like there are 2
> layers (one appears to be FR-4, but there is also a thicker, white layer).
>
> Thanks,
> -Ryan
>
> On Tue, Sep 28, 2010 at 12:31 AM, Jeff Heiss <jeff.heiss@...> wrote:
>
> >
> >
> > Youtube video: http://www.youtube.com/watch?v=DY-ZWBdrHrs
> > Album 1: "another GBC mod"
> > Album 2: "another GBC mod results"
> >
> > Just wanted to pass along my results of my GBC laminator mod. In summery: 5
> > mils is no problem at all.
> >
> > The mod was done to the blue GBC Creative laminator model 1701870. It is
> > sold everywhere, mine was purchased at www.geeks.com for $12.99.
> >
> > As I was testing the higher temperatures that we need for toner transfer I
> > found the plastic end plates that hold everything together in the laminator
> > were melting. There is a picture of the melting in the photos. I made a
> > first attempt to copy jp.gleyzes mod in the "JPG_GBC_laminator" folder. My
> > end plates cracked probably because I made the rollers too close in my own
> > template. I could not use his template because the parts in my laminator
> > were different than the ones he used. The end product of my mod is my own
> > design where the rollers pivot up and down, which is improved over the way
> > all these GBC laminators work from the factory. It uses new redesigned end
> > plates for higher temperature and roller up-down pivoting, a light dimmer to
> > control the temperature, and a cooking thermometer from Deal Extreme for
> > measurement. It works great - up to 500F and accepts boards of any
> > thickness. Three boards on top of each other go through no problem (two are
> > shown in the youtube video).
> >
> > To test the results, I used test artwork of 10 mil lines down to 5 mil
> > lines (also in the pictures) from
> >
> > http://www.delorie.com/pcb/spirals/
> >
> > Paper used was magazine paper. The results are great! The places where the
> > lines are cut in the pictures were where the toner was accidentally
> > scratched before I etched the board or did not adhere from the laminator. I
> > experimented with how many passes. Eight works fine. After soaking in
> > boiling water and removing the paper by lightly rubbing with a finger, I
> > found it useful to use a paint brush to get small pieces of paper left
> > between the traces. The bristles get where your finger can't. Although other
> > people are using other temperatures, the temperature that worked best for me
> > was 250F. The printer used was your typical office floor standing laser
> > printer at my work.
> >
> > I found it matters where you measure the temperature on the laminator to
> > get an accurate reading. Measuring on the aluminum heaters produces a
> > different temperature than between the rollers. So for a true reading, you
> > must stick a thermocouple between the rollers. I found the temperature where
> > the stock sensor was mounted on the aluminum heaters (where my cooking
> > thermometer is also mounted) is 25F higher than the rollers. So for a 250F,
> > you want a reading of 225 if using the stock sensor location to mount your
> > probe.
> >
> > Now that it was time to etch, the next batch of experiments were in order
> > to determine how much hydrogen peroxide and hydrogen chloride etchant was
> > require to etch a given area of clad. The results show an estimated:
> >
> > H2O2 3%: 3.2 mL 4.8 mL per square inch
> > HCl 30%: 1.6 mL 3.2 mL per square inch
> >
> > So, for example, a single sided, 2oz, 12" by 12" board requires 460.8 mL
> > H2O2 and 230.4 mL HCl
> >
> > Using a middle range, the board in the pictures completed in 3.5 minutes. I
> > warmed the etchant to 100F and used a foam brush to help the process along.
> >
> >
> >
>
>
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>