R5-D4's Head 3.7 - Conical shape forming???

These photo's show MY challange I have in creating the conical shape R5 has. I'm looking to use as little material as possible, to keep weight down. But also make the curving of it as easy and as simple as possible.

 The round disc on top is just a scrap piece I had from cutting out.......???

Fitting a Bad Motivator:
Drilled two holes dia 10mm. Fitted t-nuts in place.

Used jigsaw to cut out pie hole.

But because the outer curve runs over the top of the rear recessed, the jigsaw blade would hit it. So out came the dremel with the cutter fitted.

Next I cut out some angled pieces and glued them in place, for the inside faces of the pie hole. I used my angle gauge to make sure they would be below the finished level.

Cut a small strip of wood and trimmed to glued to outside edge. Then mixed up some resin and bonded it and the two sides in place.

(I placed some masking tape over the T-nut holes to stop them getting blocked up with resin.)

Also dragged out some old electronic boards and got thinking and cutting to fit inside the pie hole.

Once I'd drilled and fitted the T-nuts.......I had to test fit the Motivator.

BAD MOTIVATOR

Inside Dome, fixing points for Motivator support plate