The Wanderer, in common with most sailing boats, has a stayed mast. This means that there are wires that brace the mast to hold it vertical.
Note that this isn’t quite true. A careful look at the mast and wires shows that the section under the spreaders is unbraced by the wires. The shroud wires only really brace the top section above the spreaders. This suggests that the force of the sail in the lower section is actually taken by the mast pushing against the sides of the deck slot.
Larger boats normally have shrouds to triangulate the spreaders, then longer shrouds that pass through the spreader ends to the top of the mast. This boat, being a dinghy, doesn’t have this triangulation.
The deck seems fairly thick (around 6mm) presumably so it can take the weight of someone sitting on it.
All this implies that the existing deck slot is capable of taking substantial loads without modification. However, for peace-of-mind some strengthening is a good idea.
The underneath of the deck looks like this.
I’ve already done some grinding/sanding in this picture, but it shows the cleat location and the wave deflector from underneath. BTW this is a picture of me getting ready to sand the underneath of the deck:
One light way to increase the strength of the deck is to box-in the wave deflector, to make it a closed beam. I’ve made up some fibreglass/coremat/epoxy strips to bond on:
The strips are light and pretty stiff. I need to bond them in which won’t be fun – working upside down with epoxy. I’ve managed to avoid this job so far since the weather has been too cold for epoxy work outside. I know that the strips should be fitted while the epoxy is still green for maximum strength, but when you’ve got two small kids big blocks of time are hard to find…
As mentioned elsewhere on this blog I’d like to keep the boat as standard as possible. The standard tabernacle sides (the vertical bits) are very visible so ideally will be reused. I will need some reinforcing around the slot to transmit the forces safely into the deck. Most of the deck is bonded to the hull with fibreglass laminations so no worries about the strength of the hull-deck joint. More pondering is needed. However hopefully I won’t need to do any more sanding and I’ll try to design something that doesn’t require too much overhead epoxy work