Monday, May 07, 2012

Trough hulls, and some

I have a long shaft Yamaha 8.  This worked very good, and pushed the boat at 7 knots with very little effort.  However, it was just too small to get the boat on plane, so it never really reached the right revs.  Also, even though the reverse was adequate, since there is a dedicated high thrust propeller for this engine, I figured I would try.  The standard propeller is a three blade 8 1/2" x 7 1/2".  This propeller is 9" x 7", and with a special hub for leading the exhaust away from the blades in reverse.  Will be exciting to see how it works.

I finally got the hardware for the anchor well hatch attached.

And after this picture was taken a U-bolt have been fitted in the well for dead-ending the anchor rope.

I use Marelon trough hulls and sea-cocks.  They come in a special flush-mounting edition, but the Norwegian distributor wanted a one year delivery time for those, so I bought the regular ones.  Then, when I got them, I couldn't make my self to add such "brakes" on the outside of my hull.  Also, I was not happy with the way the AIRMAR triducer was protruding the hull.
I decided to modify the trough hulls and triducer to be more flush.  That involved making different diameter cut outs on the inner and outer skins:

Then a wide circle of foam was dug out and replaced with high density epoxy putty.  With the temperatures still here, snowing the other day, I had to rig this system for curing.

Then a step was made in the epoxy insert to leave the outside of the fitting flush with the hull.  I also took off some of the fitting (reduced diameter slightly) to avoid the rounded off part, making it more even on the outside.

Triducer seating

Water intake:

On the inside, the inner skin was reinforced with a ring of 10mm thick solid fiberglass bedded in putty. Water intake.

Placement of the trough hulls were chosen to make the least possible plumbing and easy access to the sea cocks. Previously mentioned planned build up for the head shown in the foreground.

Drain system for the flush bow cleat finally added.

Trimmed the flange on the front beam bulkhead (didn't touch any aka bulkheads)

Looking for a clever place for the electrical panel and the radio. Here, perhaps (behind the port seat back that I haven't still made)?


CrashGybe 22 said...

Ahh the seat backs, do you want the plans?
I did mine on the weekend, they are a bit of a cut and shut affair but I think that they work ok.


Tor Rabe said...


I saw your post on the seat backs the other day but could not get myself to being so rude to ask for your plans.... But yes, please, that would be very nice;-)