One of the first projects we had to tackle after getting our boat was replacing one of the bulkheads that had rotted through. Knowing more about boats might have prevented us from attempting this, but we didn’t know more and, we did replace it ourselves. A year and many sailing trips later, the mast is still standing so I guess we did an alright job. This is a step by step breakdown of how to replace a bulkhead.
Step 1: Rip out the old bulkhead. Ours was located in an extremely difficult spot to reach squeezed in between the ice box and gas tank.
Step 2: Make a template out of cardboard.
Step 3: Thoroughly clean the area where you plan on fiberglassing the new bulkhead with acetone. Make sure there is no leftover grime from removing the old bulkhead.
Step 4: Cut a new bulkhead out of marine grade plywood using your template as a guide.
Step 5: After making sure the bulkhead fits, cut tabbing slits three inches from the edge of the bulkhead. The tabbing slits should be a couple inches in length and six to ten inches apart.
Step 6: Cut strips of fiberglass cloth run them through the tabbing slits and glass them to the hull.
Step 7: Fiberglass additional layers to the top and bottom of the new bulkhead. We did six additional layers of glass after tabbing it to the hull it might be overkill, but the mast is still standing so I don’t see a problem.
Be sure to glass it to both the hull and deck of the boat.