Scurvy wrote:
mickeymouse wrote:
pro10is wrote:
I'm going to work on my gas strut design next boating season as I feel that it has great potential. I'm going to see if I can come up with a way of installing it on a TI with inexpensive parts and a design that anyone can easily copy.
Gas struts are ubiquitous these days and used for all kinds of engineering solutions. They're readily available in all kinds of sizes and inexpensive.
I was hoping Hobie would do this, but they don't apparently seem to be interested in improving the TI much more lately and have even dropped the AI from production.
I only own an AI these days but still interested see how this idea develops.
I replace the plastic bolts with Stainless & nylock nuts in rough conditions - as well as keep out lines.
You might want to rethink the stainless bolt. It will never shear off, so either the aka will collapse right there where the shear pin boss is welded, or you’ll rip the hull-mounted ball-stud out which = a hole in your hull that turn into a crack.
Regarding the gas struts, unless the whole shebang is stainless steel, they will corrode and eventually catastrophically fail. Simple is always better, so you might want to see my idea about 3 or 4 posts previously — I suggest accomplishing what you are proposing with rope and a strong bungee strap. These items will not rust and any wear is plainly visible, it’s light, it’s cheap, and is available at any hardware store, truck stop, or marina.
The purpose of the plastic shear bolts is to avoid damage to the akas in the event of a collision. However, after owning a TI for over six years and using it extensively in all kinds of heavy-duty situations, I've discovered that the akas are actually quite rugged and can withstand the usual bumps it may encounter with no issues. It would take a significantly heavy blow to damage the akas and in all my experience with the TI, I have yet to encounter such an extreme situation, not to say that it can't happen, but it would be quite unusual in normal operation.
The plastic shear bolts are known to wear and suddenly break on their own without encountering a heavy blow. I've had this happen twice for no apparent reason. Fortunately for me, this was not during a critical time and I was able to repair the problem on the water. However, if a shear bolt broke during a critical time, such as sailing in high winds or rough water, the ama would instantly collapse, and without it, a capsize could easily and quickly occur sending all occupants into the water with the TI in need of righting. That's quite difficult to do in excellent conditions, never mind bad. This is when the plastic shear bolts are stressed a lot, so the likelihood exists and is, in my opinion, a real danger significant enough to potentially cause loss of life. That's obviously very serious.
There are several decent options a conscientious owner can do to try and mitigate this dangerous situation and they've been discussed here at length. They all have their pros and cons. One of those options is simply to replace the plastic shear bolts with stainless bolts. This would not protect the akas any longer, but they really don't need such protection in normal usage, in my opinion, I've now gone several years with stainless bolts and have had zero issues in heavy-duty use. Even if the akas were damaged, they could likely be repaired or replaced. What cannot be replaced is the loss of someone's life. When you compare that with some minor structural damage, or even a total loss of the boat, it pales in comparison. The choice is obvious. I would sacrifice a thousand boats for just one person's life.
So replacing the plastic bolts with stainless ones remains a viable option with its own pros and cons like all the rest. Ropes and bungees can wear, break, stretch, and fail when stressed and impending failure is not always obvious. I've experienced many unexpected rope and bungee failures. There is no perfect solution, any one of them can fail. My primary worry is having an ama collapse during high winds or rough weather, which could likely be catastrophic. I've sailed in such conditions and I know for certain that if I or any of my passengers ended up in turbulent seas with a capsized TI, that could easily be life-threatening. So, for me, relying on a metal bolt to prevent such a situation is better than relying on some ropes or bungees, boat damage be damned.
Concerning the gas struts, these are employed for marine use extensively. Many boats use them for many various purposes. I have one on my Sea-Doo PWC. There are corrosion-resistant models
readily available and certified for marine use.
People can choose whatever option they feel works best for them, but the bottom line is that something needs to be done to mitigate the danger.