AVR-Chat

Michael Haisley wrote:
> Tony, as for your note about soldering them, it's not really that
> difficult, do you own a cheap toaster oven?
> 


We use both, well a proto reflow oven with profile controller, but a 
word of caution...

Choice of parts that can live in the oven is important, be aware that 
not everything can survive a reflow oven.

The other issue is that the surface finish on component leads degrades 
rapidly. The toaster oven tends to be a more critical process with 
respect to solder wetting and more so on fine TQFP leads. Drag soldering 
under a magnified vision system has the benefit that you tend to perform 
QA testing on the fly thus the first pass level of reliability tends to 
be better.

Pick & place lines are very carefully nurtured to provide low defect 
levels, it is difficult to emulate this in proto systems so inspection 
is king.

Having said this, the toaster oven is great for placing heaps of 
passives. High density packages still tend to be hand placed at our 
operation. A good operator can achieve this reliably at high relative speed.

Failing that, I have seen some interesting results with a paint stripper 
gun and alfoil shields ;-)

Cheers

Don