Monday, December 1, 2014

Transom Reinforcement

After 3 years of use and countless groundings a small crack appeared on the transom, right above the upper gudgeon. The transom is only 6mm thick in that area and many builders have added some form of reinforcing bit to spread the load. I did not add anything as I really like the clean look of the oval hole where the tiller sticks through. It dawned on me that an easy solution would be to just double up the transom thickness between the top of the seat and the underside of the timber doubler. Doubling the thickness to 12mm increases the stiffness by 8 times over the stock 6mm. That should be more than enough.

Shop foreman and I made a paper template of the transom doubler and laid it out on a scrap piece of 6mm Okoume.

Test fitting in place.

Transom sanded with 80 grit and masked in preparation for the doubler.

Had to come up with some crazy clamping rigs to get decent pressure. The doubler was pre-coated with epoxy and I used the thickened epoxy that squoze out to form a small fillet.  The masking tape was removed before the epoxy set and no further finish work was needed..  

Trying not to damage the existing finish by using big pads to distribute the clamping pressure. Worked out well.

New transom is bulletproof and practically indistinguishable from stock. The repair added 600 g of weight. Yes I weighed it.


  1. Great job Simon. Did you consider using a vacuum bag to suck down the repair? Tape around the edge and connect a vacuum pump.
    We are looking forward to moving to Florida next spring.

  2. Thanks, Peter. Vacuum bag did not occur to me and I have all the gear for it. Would certainly have made for a better bond. I'm a bit concerned that excess epoxy would squeeze out around the edges and require a lot of sanding and refinishing.