Lift duct

What a hassle!

Firstly I cut the ply to shape and glassed to extend the length

Next was to make something to shape it around 

The plastic around the sides is due to somehow cutting the disks too small so adding 4 layers of 0.2mm plastic fixed the issue. Now to bend around the disks.....not fun it just did not want to bend so into the pool over night it went

 Even after that it would not bend without hearing cracks all the time. I persisted and tried to fix the cracks with fibreglass and wooden plates until it dried.

Once dry I looked inside and there were some spots where it wasn't round due to the cracks. Not sure if I'm happy with it but I don't see another easy option.

I put that aside and cut the hole into the hull. Firstly I used a router top and bottom.

I then used a jigsaw and a fileting knife to cut through.

Next I sat the lift duct inside at a revised angle of 15 degrees. This is because I am using a lift motor. I marked the lift duct underneeth and trimmed with a jigsaw. I descided to keep the lift duct as I can just glass inside in the cracked low spots and sand back to a circle.

Now I aligned the lift duct. Made sure it was equal on both sides, level and at 15 degrees. I screwed in several places to hold it temporarily. I rechecked the angle and it came to 13 degrees, I was happy with that.

Then 2 cans of expandable foam has set it in place.