Julian,
Did you have prior 3d cad experience?
I ask, as i know you have not been doing the 3d printing for all that long, and you seem to have mastered the CAD side of it very well.
If you were new(ish) to 3d CAD, is it easier than i fear, or have you just spent hour after hour staring at the screen in frustration?
My cnc machine is entirely capable of 3d milling, but ive never thought i have enough of an application for 3d objects to suffer, what ive perceived, to be the harsh learning curve of 3d CAD.
As i say, im impressed with what youre up to, and am wondering if i shouldnt give it some more thought?
No 3D drafting experience prior to building the printer, but I did have a tiny bit of auto AutoCAD and copious 2D graphic experience with CorelDraw previously. This is a relatively simple shape compared with some of the things I've been working on ... currently playing a little machine to cut aluminium foil into selectable lengths and fold one end over to a selectable size.
That, if it ever works, will involve printed gears, rollers slides and leavers all driven by stepper motors and servos controlled by and Arduino.
These printers have their limitations, but it's truly amazing what they can do and just how useful they are ... there are numerous repaired and replacements and inventionettes around the house now.
If your machine is that capable and you haven't considered it, you really should. Jim will be able to give you some gen on 3D routers, but I'm sure you could buy/make an extruder head to print plastic. From Sketchup an stl file, via other software will generate G code which may well run your machine or I think there may be a Sketchup "plugin" that will generate router paths directly.
As for the 3D drafting side, as Jim says, it's not that difficult. It can be frustrating at first, but I've been playing with it for nearly a year now and it's certainly getting quicker and easier to use. 3D drafting not the most changeling part of getting a printer operational.
Probably the best thing you could do is to down load Sketchup and just have a play ... Tony needs a terminal box drawing!