Eric,
Perhaps here is an idea:
http://www.orionoptics.co.uk/DOBSONI...onian300s.html
The mounts are available separately - not sure if they are collapsible, but they are compact, not so heavy (looks like 13kg for a 12" tube) and much less prone to weather-influences than anything made out of wood.
Admittedly, 300 quid looks a bit pricey, but it should be possible to DIY with some help from a workshop - or something like it...