New Transom Using Seacast

[65Bowrider]

A new transom for CJ ...
Skip and I have just replaced our original wood transom on our 1966 Bowrider with Seacast.
I thought I would share our findings, experiences and process, in case anyone is considering a new transom for their boat.

We chose a pour-material because 1) cutting from the inside would have entailed too much work cutting and re-attaching the engine well and 2) really didn’t want to cut the outside skin either.

In summary, Seacast is a pour-able substance with fiberglass strands. It is heavier than CoosaBoard, but lighter than plywood with multiple FG layers. It is strong, drillable, tap-able, will never rot, and floats. For more detail & specs, check out their website.

Approx 3-4 days
Step 1, removed all hardware, then removed the cap to the transom with drummel tool
Step 2, tried to use long drill & drill holes in the wood from the top. Too solid, so step 3.
Step 3, used a chainsaw & cut wood out, used long-handled chisel to finish cleaning inside skins. All wood must be removed.

Approx 1 full day
Step 4, prepped transom, putting tape over holes, putting plastic on everything else we didn’t want slopped with the Seacast. I used masking tape for the plastic … should have used duck tape around the edges of the pour area. The masking tape just broke before it lifted off the overflow of Seacast. Also made drain hole plugs wrapped with saran wrap to keep Seacast from filling the hole.
Step 5, bracing the transom to maintain its shape. Added Seacast spacers between skins. Used the 4 engine bolts and 2-2x4’s to brace the outside of the transom. Used scrap plywood & 2x4s to brace inner skin too.
Step 6, make funnel to pour the very thick (like chunky oatmeal) into the 1.5” transom opening.

1 day with a 3 hour break
Step 7, mix and pour 5 gals, then mix & pour another 5 gals. Max 10 gals per pour, then must let it cure, and it does get hot. After 3 hours, it had cooled down and we were able to finish the last 3 gals of pour. As it’s poured, hammering on the transom with a rubber mallet releases air bubbles.

Step 8, cleanup of tools, easier once cured.

Step 9 will be to add an additional 2 layers of 1708 on the transom and over the transom cap. Then fair, sand, fair, sand and add some primer & paint. Then she’ll be done & better than new!

Thus far, we have been very pleased with the results and the support team at Seacast in answering all questions.

Overall, less than a week … not bad.
Here are the pictures .... !!!