Liferaft Installation

Liferafts are like relationships — hard to live with and hard to live without.

  • Choice One was size — fairly easy
  • Two was hard case on deck vs valise below — there’s no way I want to be hauling a softpack liferaft up from below in conditions that might demand its use.
  • Three was where to put it — “aye, there’s the rub…”

We went through the usual mental gymnastics on this one.

  • Stern (transom or rail) — nope, don’t want the weight back there. Interferes with coming aboard from RIB/swimming, Interferes with hoisting RIB in davits…
  • In the Cockpit — nope, hazard to it and to us (if it were to spontaneously fill) not to mention day-to-day obstruction…
  • On the spray hood — nope, wrecks standing visibility forward
  • Outboard on coach roof — yep….

Putting the life raft outboard on the coach roof dropped it eight inches and substantially improved visibility. Moving it forward from the dodger also improved the angular visibility, but we didn’t place it so far forward we had to let go of hand rails to get to it.

Mounting it provided a bit of an engineering challenge. (Photos next time…)

  1. We decided on two identical brackets port and starboard to be able to get the raft out of the way when in a slip. The unused bracket will hold a bin for fenders and dock lines. When the raft is stowed ashore (when sailing on the Bay) both brackets will hold bins.
  2. I decided not to through bolt it. Yes, this is an issue when the raft installation is vertically and upwardly loaded, but the majority of the loads are in shear.
  3. To mount it, I made HDPE pads 5 in sq. In the center I used 3/8 inch t-nuts to accept 1 inch bolts that will hold the brackets to the pads. I bored the pads for #10 fasteners and countersunk the holes. The four number #10 fasteners plus Dow 5200 provide the same shear strength as through-bolting.
  4. After positioning the brackets with all four pads attached, I drilled holes through the fiberglass and partially into the plywood below — I did not penetrate the glass below the ply. I used  a tapered bit with a drill stop to make sure of hole depth.
  5. I chamfered the (32) holes in the deck and filled each with a rot repair resin to seal the exposed plywood and glass surfaces.

The next steps.

  1. Redrill the holes to remove the un-needed resin that didn’t wick into plywood,
  2. Put a dab of 5200  in each chamfer
  3. Butter the plates with 5200
  4. Dab the tips of the screws in 5200
  5. Install.
  6. Caulk the plate-deck intersections with “almond” colored silicone sealant.

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