Homebrew PCBs

I suppose it's a matter of preference- you can't tell my soldering from
paste and I do not stress the parts using a chisel tip and quick soldering-
though it could be a thermal shock in cold climates.

I see a "mini-hoof" is what I call a chisel tip. You definitely do not want
to try SMD soldering with a pointed and narrow tip- may be this is why so
many have troubles and go to the extra effort of ovens, etc? Seldom need to
use hoof tips.

I have always liked the way parts float into place with paste- but my
homebrew boards were never quite good enough to trust 100% for that. I'm
glad yours are.

On Fri, Mar 12, 2010 at 7:55 AM, Stefan Trethan <stefan_trethan@...>wrote:

>
>
> I find I'm just much faster with paste. It does not require a tool
> change for each component like hand soldering where I need to switch
> between holding components in place and feeding solder.
>
> Using paste it is more like an assembly line, first dispense all
> paste, then place all parts, then solder all at once. I get very
> efficient doing the same thing in a row.
>
> I can set up hand soldering to be more efficient, for example by
> tinning all first pins before starting to place any components,
> then only placing parts reflowing that first pin, and as a last step
> soldering all the other pins. But I'm still slower than using paste.
>
> I'm prepared to race anyone wielding an iron ;-)
>
> There are more minor reasons for me to use paste:
> Positioning doesn't need to be accurate. Surface tension pulls parts in
> place.
> Heating is even, some parts like ceramic capacitors are not specified
> for the stresses of hand soldering.
> Overall appearance is more like production, unless you put extra
> effort into hand soldering.
>
> ST
>
>
> On Fri, Mar 12, 2010 at 12:55 PM, William Laakkonen
> <worldradiolabs@... <worldradiolabs%40gmail.com>> wrote:
> > Hand Soldering any QFP requires:
> >
> > 1. Apply flux from mini-fluxer pen or similar
> > 2. Position chip
> > 3. tack solder opposite corners
> > 4. glob solder across all pins, shorting most
> > 5. lay a *good quality (E.G. M.G.Chemical) Solder Wick across the globbed
> > solder on one side and drag the iron across the wick, lifting nearly all
> the
> > solder, repeat this for other sides.
> >
> > It may be scary to consider globbing solder on a $20 chip- I've done it
> > hundreds of times on QFPs now and have yet to lose a part.
> >
> > Elapsed time for an Atmega2560 (100 pin TQFP) about 5 minutes and no
> oven,
> > paste, etc. Mind you I *have* used paste, hot air, solder mask.-, etc.
> I've
> > used the above method successfully also with .35mm pitch parts since
> about
> > 1992 and have done it hundreds of times. No special skill or tools
> needed,
> > other than a good magnifier which you should have working with small
> items
> > anyway. I'm not a young guy either, so I must work with the magnifier
> lamp.
> >
> > After soldering many thousands of SMDs, my conclusion is in most cases,
> > solder paste is a wasted effort unless your in production. If you can see
> > it, you can solder it with a (good)  pen, solder, and wick. I use 0.015
> > solder for 0603 and up. I use .022 or 0.035 for QFP or SOIC devices and
> wick
> > up excess. I only see hot air and paste useful for things which you
> cannot
> > reach with an iron (flexible kapton boards with blind connects, BGA,
> ETC)-
> > and what hobbyist(s)) would use such parts unless they were free? I do
> see
> > "homebrew" in the title, which to me evokes a sense of doing more with
> less
> > and experimenting with new techniques.
> >
> > Loading and soldering is only one side of a homebrew_PCB.
> >
> > Regards,
> >
> > Bill
> >
> > On Fri, Mar 12, 2010 at 1:28 AM, Henry Liu <henryjliu@gmail.com<henryjliu%40gmail.com>>
> wrote:
> >
>  
>


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