--- In
Homebrew_PCBs@yahoogroups.com, Adam Seychell
<adam_seychell@y...> wrote:
>
>
> roel_cnc wrote:
> >
> >
> >>What type of etching solution do you use ? I assume...
> >
> > the pcb oscillate about 10 cm
>
> Does it oscillate side to side movement or is it spinning ?
>
> > 10 nozzles per side makes 20 off it
> > volume off etch is about 25 liters
> > i use the fe3 the brown fluid.
>
> Is your pump a centrifugal or a diaphragm type ?
> Do you have a model number for the pump ?
> I found a company, www.flojet.com (web site seems to be down at
> the moment). They make a large range of relatively small electric
> diaphragm pumps. These pumps are higher pressure and low volume
> compared to centrifuge type. You probably know that spray nozzles
> need good pressure to work effectively.
> Did you consider using proper chemical etching nozzles ?
> What is the spray pattern on the nozzles you are using ? Fan or
> cone type ?
> I have read that the spray pattern and the positioning of the
> nozzles is critical for uniform etching. Did you experiment with
> different nozzle configurations until you were happy with the
> etching results ?
>
>
> > the soldermask works the same way - only after developing extra
uv
> > cure and after that an oven cure for 60 min at 159 C if you can
get
> > the same film (dynachem laminar DM)
>
> Thanks, it seems I should try and get hold of some of this
> soldermask. I wonder if its more expensive than photoresist.
> Here is the datasheet for the laminar DM;
> http://www.interflux.pl/wwwpages/products/shipley/laminar-dm.pdf
>
> I guess its not possible for soldermask to be stripped off the
> board after it is fully cured. Methylene chloride paint stripper
> should work, but that will kill the epoxy laminate material too.
---> why should you remove.!
some links
www.hendor.com for pumps i use m62 6000 liters p/h
thats why i use 25 liters of etch and dont forget the anti foam
additif or it will rise up to the sealing. :)
www.bete.com for the nozzles i use similar to the nfs12 Fan 120°
4L p/m 20x that makes a total of 4800 L p/h
heater is a 1 kw flat wire teflon coated no url aviable yet
gr. Roel