Homebrew PCBs

I don't believe a simple hot air gun setup will work for a BGA part 
with 500 pads. You need to preheat the board, and use a bottom heater 
to ramp up the heat as well as a top heater. And with more products 
going Lead Free, it will take a lot more heat and a lot more complex 
heating profile to properly reflow the parts.
I had worked on a BGA machine before, the big expensive automatic 
type... Even then it would take a LONG time to properly create a 
reflow profile to get maybe 95% success rate. (of course we were 
working with like 1000+ pads) I can give you some tips and pointers, 
but for only doing 1-2 a year, it can get pretty expensive 
(especially with FPGA's) and frustrating when you fail at reflowing 
the part.
--- In Homebrew_PCBs@yahoogroups.com, "timbomcnuckle" <jaydag71@...> 
wrote:
>
>  hey!, I haven't used a hot-air station yet but I have done the
> over-reflow a bunch fo times and I would take the time investment 
into
> making your own rather than the alternative- especially if you are
> only oding a few boards per year! Elektor did a great version of the
> taoster oven re-flow controlled with an AVR I think, lcd display,
> programmable curves, precision control (within reason),, I think the
> only complaint was lack of insulation, but you can always stuff with
> rockwool or something.
> 
>  I have used old style black&decker toaster-oven without any
> modification a few times but I got a better one now that I still 
need
> to finish. gluk.
> 
> --- In Homebrew_PCBs@yahoogroups.com, Harvey White <madyn@> wrote:
> >
> > On Tue, 02 Oct 2007 18:52:12 -0000, you wrote:
> > 
> > >Recently, I started making electronic circuits as a hobby and now
> > >I want to do more complex stuff like FPGAs.
> > 
> > That's ok, and presumably they don't come in PLCC carriers (a 
shame),
> > but you might not want to use BGA's simply because of the 
soldering
> > problem.  Any other alternatives?
> > 
> > No opinions otherwise, you're far ahead of my aspirations in this
> > respect.  (if not others).
> > 
> > Harvey
> > 
> > 
> > >For that I need to solder BGAs. I'm considering buying a hot air 
> > >rework station. So far I'm looking at either 
> > >   Aoyue 968 http://www.aoyue.com/en/ArticleShow.asp?
ArticleID=359
> > >or
> > >   Aoyue 99* http://www.aoyue.com/en/ArticleShow.asp?
ArticleID=375
> > >  The first one has a digital display and a soldering iron while 
the 
> > >other one has a manipulator.
> > >  I already have a good quality soldering iron. Do you think the 
> > >manipulator would be more useful ?
> > >
> > >  The goal is to be able to build prototypes with BGAs (maybe up 
to 
> > >500 pins). I only need to build like two boards a year for 
myself, 
> > >and I am not concerned about the time it takes, as long as I can 
be 
> > >reasonably sure that it will work.
> > >  Or maybe, I should make a temp controlled toaster oven and 
> > >dispense with the rework station already.
> > >
> > >  Could someone with more experience share their advices ?
> > >
> >
>