Homebrew PCBs

I'm sure it also depends on the software. I haven't tried autorouters
often because routing effort is really minimal once the placement is
just right, and it gives me the chance to sanity check every
connection. I haven't seen an autorouter that can change placement
while routing, not sure if they exist and you probably would have to
sell your soul to the devil in exchange. Every pre-routing auto-placer
I have tried so far (not many) was just ridiculous.

Anyway, usually I found every autorouted result completely
unacceptable, endless square cornered traces, lotsa vias, no sensible
approach to differing trace width, etc..

What really made me look astonished was when I tried the "pull tight"
function in Pulsonix. This could straighten out really messy routing
into nice 45° rules to a state where I could probably tolerate it.
Maybe combined with this function an autorouter could work. But then
that still leaves you with placement and some cleanup and it's likely
no faster than routing manually.

Also some software is really good at cleaning up traces by hand
(shoving them around, mitering corners and such), while other software
makes it more difficult. With eagle I frequently find myself in a
situation where it is quicker to just rip up and re-route. This makes
it rather pointless to use an autorouter if you only rip it all up
again one by one anyway.

ST

On Sat, Oct 10, 2009 at 4:20 PM, sailingto <sailingtoo@...> wrote:
> I'm sure glad to hear that I'm not the only person who doesn't like auto-routing.  It just doesn't go where I want, and when I try to clean up the rat's nest of traces it seems to take longer than manually routing from the start.
>
> 73 de Ken H