Homebrew PCBs

Phil,
When I started trying to figure the toner fusing point, I went to the HP 
site and looked up the MSDS for my particular toner.
I can't find it right now, but as memory serves me, they listed the 
softening point at 100 to 150 degrees C.

Might give a decent starting point.


It still gives a broad range At 06:14 PM 2/11/2004, you wrote:
>If the only problem I was having is to fill in an occasional pinhole,
>I'd call it good.  Given the amount of manual fussing you have to do,
>that seems a pretty minor point.
>
>I've been experimenting with this technique but have yet to get a
>laminator becuase I've gotten reasonably good results from the iron
>approach.  It seems to me that there are a number of variables you
>have to deal with.  each one can ruin the process.
>
>1) fusing temperature
>1a) toner fusing point
>1b) fusing time
>2) fusing pressure
>3) thickness of toner
>4) quality and cleanliness of copper substrate
>
>I think 2) is a huge issue in that there is fine line between too
>much and not enough.  I found that even modest pressure causes some
>smearing of toner (and the widening of traces). Its my opinion that
>little pressure is needed, you just have to ensure that the toner
>makes contact with the substrate for a long enough time at the fusing
>temperature.  i.e., it has to melt and be in contact with the
>substrate long enough.  I've gotten good results with letting the
>iron be all the weight needed.  I also do not apply ANY lateral force
>as that seems to cause smearing.
>
>Since I print on an inkjet and then use a copier for my toner
>deposition, I am able to control the amount of toner pretty well.  I
>tried a non-scientific range of toner densities and found that you
>want it to be fairly thick, especialy for large ground areas.  How
>ever, the thicker the toner, the easier it is to get smearing.  less
>pressure is needed in that case.
>
>It probably goes without saying but preparation the the board is
>critical.  I've gotten good results with a very fine emery cloth to
>create a rough surface (i.e. significantly increase total surface
>area to allow better toner bonding).
>
>Toner fusing temperature is tricky because different toners have
>different fusing points and it appears the substrate material type is
>a factor as well.  For example, ricoh has a lower temperature toner
>to allow shorter warm up times for their printers.  does anyone have
>pointers to information on fusing temperatures for varous toners?
>I've googled until my eyeballs hurt and found only scraps of info.  I
>may just have to try an experiment.
>
>
>Phil
>

Bubba

OLDER THAN DIRT
Country Bubba
(Actually the inventor of Country and Bubba)
In God We Trust

axtein@...
LaGrange, GA

http://ns1.dicomm.net/~axtein/dro


[Non-text portions of this message have been removed]