Transom Repair of 5.1 Power Cat

The transom on this power cat was badly rotten. It had to be rebuilt ready for new motors to go on.

The only way to get to the transom was to cut out the base of two wells on either side of the boat. When doing this, there was a surprise as water came gushing out of the cuts being made. Cutting had to stop and almost 10 litres of water was drained out of each side of the wells.

When the base of the wells were finally removed there was another surprise. There was still another panel underneath the base of the wells. They also had to be cut out to reach the transom. The water that came out appeared to have drained from the floor back onto this second panel but was trapped there as it had no where to drain away to. Once this panel was removed there was a compartment full of plastic bottles that were used as floatation. These were removed. There was now a large empty compartment and I could get to the transom.

The inner skin of glass was removed from the transom and the rotten wood cleaned out. After the transom was clean, new 20mm marine plywood was cut to size and fitted. It was impossible to put the new plywood in as one piece. There wasn't enough room to fit it. The new transom was made in two pieces with a 50mm lap joint joining them. A top piece of ply went across the top of the transom to thicken it and also further strengthen the joined piece.

Once all the ply was cut it was glassed into place. All gaps around the ply was filled with a high strength cabosil filler and the final layers of glass were put over the new work.

It seem a good opportunity to make use of this newly exposed compartment. To improve it the remains of the second panel that held the water as mentioned earlier was cut flush to the wall under the combing and sealed with fibreglass. The floor and walls of the compartment were sanded and the new transom and compartment were flowcoated.

The transom was rebuilt and a new compartment created.