Re: gEDA-user: SMT/Through Hole Mix

["Phil Taylor" <phil@xxxxxxxxxxxxxxxxxxxxxxxx>]

You can get a solder paste syringe sample kit from a company called EFD. 
It'll last you for a long time doing prototypes.

I use a pair of 'OO' size strong tip tweezers, which are straight.  A 1/64"
soldering iron tip is good.  A way to vary your tip temperature is also
helpful--e.g. series resistors, variac, or a proper soldering station.  You
can do 0603's and .050 SOIC parts, which significantly broadens your parts
selection horizon, with this rig.

Later I started using a kitchen hotplate as a pre-warmer only, then follow
thru with the reflow with a hot-air reflow.  There are a lot of Asian made
units available and people seem to like them okay.  This tool is extremely
handy.  I have an XYTronic--nothing special about it, but it works well.  I
think there are some that are even cheaper now.

I store all my parts in small zip-closure baggies.  All the same size, in a
half a doze parts-bin drawers.  Storing a 1000 resistor values is pretty easy
on space and overhead.

Best of all, this is the fastest way to 'stuff' and solder boards, well, at
least if you're doing it yourself.

Phil Taylor


"hwb" <haoweibing@xxxxxxxxx> wrote:

> I am interested on SMT board as well. For making only 1 or 2 prototype 
> board, my concern is that, for example, I need to buy a roll resistors which

> at least are thousands of them. In addition, can I have some advises on what

> tools are necessary for doing SMT board.
> Bing
> 
> ----- Original Message ----- 
> From: "Stuart Brorson" <sdb@xxxxxxxxxx>
> To: <geda-user@xxxxxxxx>
> Sent: Tuesday, May 16, 2006 9:58 AM
> Subject: Re: gEDA-user: SMT/Through Hole Mix
> 
> 
> >I don't see why you wouldn't do as much SMT as possible.  There is no
> > advantage to though-hole stuff that I am aware of.  (I welcome
> > corrections on this point.)  You can do hand assembly and rework of
> > both through-hole and SMT down to (arguably) 0603
> > components (or maybe even 0402 if you have good eyesight and non-shaky
> > hands).  As for power stuff, lots is availale in SMT versions, so
> > that's not a consideration.  Through-hole stuff is going obsolete
> > anyway.  Finally, SMT stuff lends itself to automated assembly, which
> > -- in the long run -- will be cheaper.
> >
> > Ultimately, you should talk to the folks who will stuff your board.
> > They can offer better advice tailored to your situation than we can
> > here.
> >
> > Stuart
> >
> >
> >>
> >> I have a design that's very low production quantity(~50 pieces per year)
> >> that has a couple of chips that only come in surface mount versions. 
> >> Does
> >> anyone have any opinions on what the lowest cost assembly option is with 
> >> the
> >> design, is it better to attempt to do the whole board in SMT with just a 
> >> few
> >> components through hole(things like power components) or do you do the 
> >> board
> >> mostly through hole except the 2 surface mount chips(noting that one is 
> >> 48
> >> pin tqfp).  Or do you go with two boards, one with all surface 
> >> mount(except
> >> for perhaps the connector between the boards) and then do a second board
> >> with all the through hole components.
> >>
> >> We've managed to keep things strictly through hole until this point in 
> >> time.
> >> Unfortunately it's no longer viable to go all through hole with new 
> >> designs
> >> of any complexity.
> >>
> >> I appreciate any opinions.
> >>
> >> Thanks
> >>
> >>
> >>
> > 
> 
>