Homebrew PCBs

With supported rails the only time you need to increase the size is if 
you increase the load. Increasing the overall size of the machine a bit 
isn't going to increase the loading on the rails by much. Really you 
need to work around your materials. For instance GFS is available in 18" 
lengths so if you use GFS it makes sense to design the mashine around 
18" rails.

Les

On 15/09/2010 02:33, Herbert E. Plett wrote:
> Not at all true.
> If you lengthen a rail you will also have to step up the size ->  more expensive!
>