To shear or not to shear...

Not always smooth sailing

Recently I have been contemplating the concept of the 'shear pin' as used on the Hobie Adventure and Tandem Island kayaks. In both boats there are 3 of them, one of which is the rudder pin. No matter how much wiser you think it might be to replace the default rudder pin with something stronger, it probably isn't. Under stress that pin is supposed to shear and this is to prevent anything more critical from breaking. This is generally well known and accepted by AI/TI users; the rudder pin is basically a fuse. Better the pin break than to have the gudeon ripped straight out of the transom, for example. Fair enough.

The other two shear pins are for both aka braces (both left and right) and are there for much the same reason - to prevent further breakage should stress or shock cause one of the shear pins to fail. However, in my opinion, the consequences of having one of these shear pins give way have potential to be much greater than just breaking something else. The more I have thought about it, the more I have started to think that I'd rather have a solid shear pin for the akas and risk further breakage instead of dealing with the consequences that are likely to occur should one of these snap while sailing. The very thought of it inspired me to replace my existing nylon shear pins with stainless 1/4" bolts a couple of weeks ago. This may very well void any warranty related issues that may arise from doing so, but I'm more interested in safety than I am who or what is responsible for a costly breakage.

Ironically, today my paranoia was validated when one of our members explained to me today that just last week a leeward shear pin snapped on him while sailing in on low surf, and when he told me this I knew what he was going to say next. The leeward pontoon folded immediately and physics took over as his AI toppled over on it's side. Because he was in shallow water, this did indeed result in several breakages anyway and it could be fairly said that these would not have occurred if the pin didn't give in. Nor is it likely that he would otherwise damaged the akas or connectors had he been using steel pins. In this case the shear pins didn't prevent a breakage - it could be fairly argued that they actually helped contribute to breakages, and costly ones. A mast was broken, along with a few other components (lets not mention the now multi-piece rods).

I've been using the AI for a few years now and put more miles on the water using one of them than anyone I know. So far I am yet to encounter an instance where the pontoons were put under such load or shock that was likely to break anything. Put another way, I tend not to sail my AI into solid objects. Thus, the likelihood of my sailing pontoon-first into a jetty wall are pretty much nil. So I really don't see how I'm likely to cause any inadvertant damage to any part of the hull through shock to the akas. As such, the shear pin just seems a little unnessacary.

What I have seen happen, however, are aka shear pins breaking while the boat is being sailed (usually for no other reason than wear and tear) and most often this occurs to the leeward side. The stronger the wind, the faster that yak is likely to topple over. This is bad if in the surf zone because then further breakage is more than likely. Even though extraneous breakage is less likely to follow a topple-and-turtle in deeper water, this instance might be more of a safety issue. Either way, if you're sailing in anything more than low winds, an unexpected shear pin snapping could well result in an unexpected capsizing. And as far as I'm concerned, this is not only more likely to occur than damage being caused to the hull via shock to the akas, it's also a worse case scenario.

Think it through. If you do so and reach the same conclusion as me, there's really only one obvious answer: a stainless steel bolt to replace the default nylon one. But that's a decision that could have potential consequences, so it's a trade off no matter how you look at it. It's a question of lesser of two evils.

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DB: Hi guys, long time no see
DB: catch up later
Josh: heya DB, how goes it?
Carl: hey Db's back...did you get parole or early release for good behaviour?
DB: Hey guys. Haven't been able to access the site for ages for some bizarre reason. Just re registered with a different email.
We just had our local exchange out of order too and no phone but that seems ok now.
Haven't done much fishing of late but I am a member of a local fish stocking group which stocks two small dams locally.
Planning on getting off shore again soon but I am fatter than ever an more unfit so I'll be taking it easy and sticking close to shore. Chat soon :D
DB: Morning Carl.
XDCAMMER: Hey DB, good to see ya still alive,. I was talking to Tas yesterday (Fri) and he said to pass on his best to all you guys. He has bought a PA 12 and is fitting it out. All the best mate, power walking is a good slimmer. WHATS WITH BALLS? Cheers to Kate. xD .
XDCAMMER: Imagine what would happen to an AI mast if it were hit. Lucky boys. I hate lightening.
DB: Anyone home?
DB: Later folks. :D
Guest_3610: Salmon fishing from the yak in
Jenkins: Hi Josh
Jenkins: what size rods do you use on your adventure
Josh: Jenkins, I have 6 rods, all of them Nitro. 2 x Godzilla for trolling, Viper for jigging, just got a Magnum Butt Distance Spin for casting lures into frenzied fish. Voodoo for plastics for small to medium species and a ultra bream for finesse fishing/squid, etc. Taking a Godzila, Viper and Magnum But to Fraser Isl next month
Jenkins: Thanks Josh
Josh: You're welcome
XDCAMMER: If I get asked for another "Hobie canoe" I'm going to SCREAM!
Jenkins: This might sound like a dumb question but what would you consider and moderate wind speed to go fishing and what size swell?
Carl: i think 8 - 12 knots is a good wind speed for trolling on an AI...i don't get swell too much here only get chop from wind up to 1.5 m when i get wind v current...washing machine conditions...
Guest_9733: With regards to swell, it depends very much on wind conditions at the time, and whether or not there are white caps. Trolling at wind speeds Carl suggested is great for pelagics, slower for reef fish is usually a bit better
Jenkins: Thanks for that, cheers.
XDCAMMER: I wouldn't be eating that cod. I wonder if Rapala will bring out a new shaped CD Mag, not sure where you'd put the hooks tho.

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