What we do

Multihull yacht design and construction has come a long way since I created my first design in 1986. Evolution never ceases in nature and there’s no reason for it to cease in yacht design and manufacture either. 


Our journey starts with asking questions and imagining whats possible.

 We craft the curves, finesse the forms. We bring in the technicians, the mathematicians, sometimes the magicians. We call up the makers and the movers and shakers.


We’re here to bring you the latest in design technology in hull shapes, in styling, in engineering, to connect you with the products and the services that will streamline the build process and bring your own yacht life with the most cost effective build methods we can conjure. 


Browse the designs. Check out the people and the companies we’re partnered with in The Partners Network.


Join us on our journey, or let yours begin when ours is done.

What you’re imagining just might be possible.

And if it’s not we can probably make some magic happen anyway.


Tony Grainger


Not the first design but one of the first. And she's been first in fleet more than once. She's been called ATL/Oaks. Dux Nuts and Moving Finger. She'll always be called one of my favourites.

Multihull Design Shop is Live Now

t's a one stop shop where you can where you can browse and purchase layout drawings, sail plans and technical information multihull designs from Grainger Designs and Rocket Factory Trimarans. You can pay for the design information you need with Paypal and you'll receive a link that will allow you to download the plan or the booklet you've purchased in Pdf format. 

The site address www.multihulldeisgnshop.com

It's early days, We have a lot of work to do to upload information and improve the functionality of the site - but check it our and let us know where you think we can make improvements.




This is the first rendering of the new custom cruiser for Troy and Annette Forrest to be built on the Queensland Sunshine Coast. Until it gets its real name we’re calling it Design 258 and it’s based on the Raku 48 design but with expanded

accommodation space for extended family cruising.

This design features twin helm stations aft, four double cabins and daggerboards for optimum windward performance.

Enquiries for this design are welcomed.

The 8.5m (just a whisker under 28") sports cat we're designing for Johannes Romkes and we've taken a decision at corporate level to make plans available.

The hulls are closely based on the under water shapes we used on Mad Max. Yes, that was some time ago, but as long as at least one of your hulls are going to stay in the water these shapes have proven to about as slippery as they come.

Work is now under way on detailed construction drawings. Plans are available for sale now and kits may be available in the future.