Hi Snowy,
Originally designed, the cylinders and their fins were to be printed in quarter segments and glued together but it soon became apparent that due to warping and lack of an effective adhesive this would be difficult, so I re-designed the cylinder assembly as per the drawing. Warping remains a problem but, with help off the forum (and metres of wasted PLA!), I have learnt how to minimise its effect.
Yes, the CAD work has been at least half of the total effort. All of the components though are basic solids added or subtracted from each other, so nothing too challenging (luckily!) for the Autocad 2007 I am using.
Many thanks for the nice comments from all the forum members. The Ultimaker is proving to be excellent for my model making and I am finding more and more uses for it.
Regards,
Pete.