outboard mount reinforcing-FS14

Boats up to 15' for oars, power or sail. Please include the boat type in your question.
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brackish
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outboard mount reinforcing-FS14

Post by brackish » Mon Mar 14, 2016 5:51 pm

I'm finishing up my FS14 and am wondering what folks did if anything to reinforce the outboard mounting area. My transom is the design thickness at the motor mount area and it has been glassed all the way up both inside and out. I'm going to mount a 9.9 four stroke with 20" shaft, electric start, so 104lbs. Not really interested in adding more transom weight, but any opinions about this. Add a thin aluminum plate? some large fender washers? just go as is?



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jacquesmm
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Re: outboard mount reinforcing-FS14

Post by jacquesmm » Wed Mar 16, 2016 10:21 am

As designed, the transom can take a 15 HP. No need to add anything especially since you fiberglassed everything.
The plywood total is 3/4" plus the glass, you must be around 1" thick.
Those boats are very strong as designed.
A metal plate, Al or SS is always nice to take the engine clamp and spread the loads but not really necessary.
IF you installed a 25, I would add a layer of 3/8 to the clamping board.
Jacques Mertens - Designer
http://bateau.com

brackish
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Re: outboard mount reinforcing-FS14

Post by brackish » Wed Mar 16, 2016 12:17 pm

Thanks. I think, if anything, I might put a couple of SS fender washers on the clamp screws and leave it at that. This boat transom above the casting deck is actually 3 @ 3/8", so 1-1/8" thick and with the glass mine measures just under 1-1/4".

Looks like launch in April if the weather for final inside paint treats me fairly.

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Re: outboard mount reinforcing-FS14

Post by jacquesmm » Wed Mar 16, 2016 12:41 pm

Yes, you are correct: as designed, the transom has 3 layers of 3/8 at the clamping board. More than enough for a 25 HP.
I should have looked at my own plans!
Jacques Mertens - Designer
http://bateau.com

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