Ozpulse wrote:
It would be great if we could get some approx. dimensions for a gas sized rigger.
ie. tub min/max length/width/height, sponson/boom width/length/spacing etc.
Dont want anybodies secrets but something to give the builder a chance to go it alone and design thier own build from a basic set of dimensions.
Thanks,
Chad.

Most 25cc class GAS riggers will be in the 45" - 50" overall length.
Tub alone in the 42"-48" range. There are a few smaller yet, but under todays power IMO the longer hulls are really the more stable at speed.
Tub widths generally 5" inside with some shoehorning in on special mounts narrow as 4". Really when one scratch builds, the HARDWARE to be used sets the design perimeters somewhat.
3 point or 4 point designs generally require different AOA on front sponsons, after plane distances and attention to C/G location and weight distribution sponsons and prop will carry are all in the design mix.
Rigger are by there looks the simplest in design, but in reality the MOST difficult to actually get right
Unless SPLASHING a known hulls design attributes going about scratch designing and building a rigger would require a LOT of luck.
Honestly tho if NOT having years of hands on experience with Riggers, doing blind "Got an Idea" building would require extensive trial and error
**
That said, IF a modeler were too start a project and share WHAT DESIGN PARAMETERS they wished to incorporate ? ..... You could get guidance by those who have been there and done that 
..... Only wish they were such simple beasts.