--- In
Homebrew_PCBs@yahoogroups.com, Stefan Trethan
<stefan_trethan@g...> wrote:
>
> >
> >
> > This is one of those things you find out about machine control.
> >
> > with some practice, you find that by being 0.5mm from the pcb, and
> > starting the paste to flow and presising the syringe 0.1mm, that
some
> > exact amount is dispensed.
> >
> > this will be repeated on every occurance.
> >
> > One thing that comes to mind is the surface adhesion. If the
paste
> > does not adhere to the surface, it will not stick and the next pad
> > will get double.
> >
> > But, each of these things are things you can control.
> >
> > Dave
> >
> >
>
> You basically say whatever the machine does wrong, it does it wrong
the
> same way every time, right?
>
> What about the software, how do i get the file i need to feed the
cnc?
> No point in building a expensive cnc machine and then it is
impossible to
> get the right file.
>
> I reckon the "generating the file" thing would be even harder if
one
> thinks of pick and place?
>
>
> ST
I think the software would be pretty easy if you can write software.
TurboCNC is a very low cost package that handles g-code.
If you call out a drill hole for every SMT pad, or wherever you want
to dispense paste, then the g-code can use that as the basis for
moving. You have full control over Z axis speed rate, or feed rate.
so you can rapid to a point and then the driller would think it was
going to drill, but your special code would tell it to dispense.
I would do that in Excel only because I am do familiar with Excel and
have no problem with G-code.
Dave