Beam Replacement Walkthrough
Please take the time to review this comprehensive PowerPoint presentation by Thomas Egan regarding the dreaded beam replacement project on the Cal 40 Misirlou.
Misirlou Head & Beam Refit Presentation
File Format: Microsoft PowerPoint (.pptx)
The Dreaded Beam: Sinn Fein Experience
By Peter S. Rebovich • Cal 40 Sinn Fein
“About ten years ago we replaced the beam in our 40. The yard price for a new beam was approaching about $3,000. Instead, we hooked up with a stainless steel dealer who provided material cut to our specifications and shipped for less than $600.00. A retired welding friend duplicated the beam in shining stainless steel for $500.00.”
“This was a great winter project, and we reaped the benefits of being able to point higher and keep the rig tuned.”
Removal & Replacement Sequence
- Removed the bottom of the standing locker common to the shower.
- Removed the head unit and the lower section of the sink countertop.
- Cut and removed the bottom four inches of both bulkheads.
- Cut the top of the interior pan roughly two inches below the top.
- Detached the beam from turnbuckles and bulkheads, then extracted it from the cabin.
- Reinstalled via reversal: re-tabbed fiberglass pan, repaired bulkheads, and replaced cabinetry.
Structural Note: During Superstorm Sandy, severe damage occurred on the starboard side of Sinn Fein. While some fiberglass work needed redoing, the bulkheads and stainless beam structure remained intact with little to no damage.
Detailed Beam Extraction & Material Choice
By Cary Smith
Here is the procedure I used to remove and replace my Cal 40 mast beam without cutting the bottom off the main bulkheads:
1. Forward Floor & Locker Preparation
Cut the forward floor sections into two parts, separated just aft of the forward cabin/head bulkhead. This allows the forward floor liner to slide forward slightly, creating clearance for the head floor to come out. Remove the cleat on three sides of the floor and unbolt/remove the head door.
2. Fiberglass Cutting & Cabinet Removal
Use a 4½″ angle grinder with a thin cut-off wheel and a bi-metal Reciprocating Saw (Sawzall). Carefully follow the hull contour to avoid cutting into the hull skin. Remove the front of the hanging locker, small fore/aft bulkhead, head unit, plumbing, and entire head cabinet.
3. Mast Step & Settee Disassembly
If mast step fasteners cannot be unbolted, cut around the step while leaving enough floor material to feather and bond back later. Remove the settees by unscrewing the small retaining blocks, tipping up the assembly, and removing the 1x wood slides near the bulkhead to access the aft bonding.
4. Unbolting & Extracting the Beam
Cut the single layer of fiberglass tabbing holding the beam to the hull (fore and aft of the bulkhead). Unbolt the beam (~175 lbs), slide it forward, tip it up head-side up, and maneuver it out of the companionway with assistance.
Material Debate: Galvanized Steel vs. Stainless Steel
| Material | Approx. Material Cost | Key Considerations |
|---|---|---|
| Galvanized Steel | ~$350 | Lower material cost, easy to weld/fabricate personally. Lasted 45 years original. |
| 316 Stainless Steel | ~$600 – $1,000 | Superior corrosion resistance, higher fabrication/welding cost. |