The area around that little stud at the base of the mast holder is the highest stress point in the entire design. Leverage plays a large role in the amount of stress in this area, and the stress on that little stud. Think about it, you have an 18ft pole held 1ft from the bottom (where the delrin bearings are). If you equate this to lifting a car with a lever, imagine taking an 18ft pole placing a brick 1ft from the end, then lifting your car (a small car) with one hand by pushing down on the long end of the pole. This amounts to several thousand lbs of force (under the right conditions of course) applied to that little stud and the walls of that little brass insert in the forward/back direction, (the brass insert is embedded inside a pyramid that is molded inside the hull, the pyramid takes the bulk of the force)) When adding massive sailsets to my original TI (back in 2010) I of course tested everything to determine all the potential failure points (I'm a design engineer, lol, thats what I do), I was able to pull the main control line tight with the sail completely unfurled, just a quick tug on the control line snapped that little stud ( the old stud design)as if it wasn't there at all. The 'side to side' force (structure is strengthened by the V-braces) posed no problems. Obviously if your not planning to add giant sails (ie... jibs, spinnakers, wings,etc), there is no need to do anything, the built in stud (if it's tight, and working), and the mast strength is all within the design spec's of the mainsail forces. Just make darn sure all the bolts and pieces remain tight.
However when adding say a 135 sq ft spinnaker, and/or a 35sqft jib to the design, those big sails generate way more force than the original design can withstand. The strength of both the mast itself, and that little stud at the base of the mast holder are greatly exceeded. On all my designs I added a small aluminum plate inside the hull that fits between the back of the mast holder, and the front of the mirage drive well, I then made a small dam around the bottom of the hull around the mast base, and poured epoxy into that area, ( the alum plate is buried in epoxy), all completely removable of course. All my designs include a rear stay line that only allows the top of the mast to bend forward no more than 1ft, (the rear stay line prevents the mast (and stud) from breaking when the big spinnaker is deployed). You can reason it all out yourselves, lets say for example you are in 20mph plus winds, you open up the main and spinnaker showing around 220sq ft of sail area, the boat is easily propelled to 20mph, now go to one of those online calculators that calculate how much horsepower is required to propel a displacement hull to these speeds, (required horsepower goes up exponentially with speed it appears). According to my calculations anyway, the horsepower generated by the sails alone is in excess of 20hp (maybe more). The boat as shipped from the factory is not designed to withstand those loads, (lol, actually no part of the design, (ie... mast system, the hull itself, AMA's and AKA bracing, rudder, etc, etc, etc). I'm not suggesting anyone not add additional sails to their TI's, or not to mod your boat out, (it's your boat do as you please). I'm just saying if you are planning to do so, you need to understand the forces involved, and the limitations of the current design, then work around them.
Bottom line is the most expensive repair on the boat is if that little brass insert at the base of the mast gets pulled out or damaged beyond repair, this scraps out the entire hull, you will need a new hull (expensive), so in my opinion that little stud and the V brace system should be inspected periodically. No need to do anything drastic (designwise) if the boat and sail system remains stock (what most prefer), in other words the design is sound on the factory stock TI, as long as everything remains bolted together and tight. Sorry I'm an engineer, I tend to over explain things... Hope this helps FE
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