Homebrew PCBs

On Thursday 07 July 2005 12:17 am, Earl T. Hackett, Jr. wrote:

> I spent 12 years trying to teach companies such as IBM, HP, Sperry Univac,
> Burroughs, and countless board shops how to build PCBs.  There were
> technical successes (Sperry in Bristol, TN, and HP in Garden of the Gods,
> CO were memorable) and failures (IBM, Austin, TX), but in the end economics
> trumped technology - except in the cases of the Mafia shops that were
> laundering money - and essentially all PCB production has moved to SE Asia.
>
> So I have a bit of experience making circuit boards.

Given that,  can you give me some idea as to why it is that some boards seem 
to be so easy to work on (in terms of repairs etc.) where you can unsolder 
parts,  install new ones and solder them just fine,  while at the same time 
with some of the same kind of parts it seems that no matter how careful you 
are you end up yanking the plating out of the hole,  perhaps lifting the 
trace on one side,  etc. -- using the same tools and methods?

I can *see* some differences between boards.  I can *feel* some differences in 
terms of being able to unsolder or to remove the component or whatever,  and 
differences in the weight of the copper,  etc.  But I don't have the 
experience in making boards to be able to quantify this stuff.

And why the heck are so many boards made where the bend the component leads 
over so tight against the board,  making it so difficult to deal with later?