hog rings

Does anyone know the correct size hog rings to use on bungee cords ? Anyone have a recommendation for the purchase of hog ring pliers and rings ?

thanx,
bill

Depends on the size of the bungee (shock) cord. You want the rings to be just large enough that putting two ends of the desired bungee will just lightly squeeze in-between the ring ends. If there is any noticeable slop or space, drop down to the next smaller size ring.

Most real hardware stores carry good hog ring pliers. West Marine has them and hog ring assortment kits. Hobie also lists piers and rings in their accessory catalog.

cooldudecaptain:
If your doing a double bungy mod, actually there is a much simpler and better double bungy method that works way better than some others I have seen, and also prevents the AMA from any possibility of coming off (no hog rings necessary, just knots). Actually you can easily sit on the AMA without fear of it ever coming off or over stretching the bungy's.
Here is a pic of my setup, I've been using it for a while now and it is rock solid and easy to rig, just slip the cinch knots over the post, by doing it this way with the Hobie grey spectra rudder line (which is way over 300 lb test). You have room to add other stuff over the top of the post (I use those posts for everything (ie... including, tramps, ladders, holding spray skirts, etc). We use our TI for mostly snorkeling and scuba diving down in the keys, and often have 5-6 people all snorkeling or diving off the boat. Many like to sit on the AMA's, and the easiest way to get on board the TI is to climb on board over the AMA's. If you look at the small piece of spectra string to the right of each bungy, this prevents the AMA from stretching any more than an inch or two, then the spectra line tightens up (works just like your rudder up/down line does).

Of course you can do whatever you want to do, but I found this to be much easier, stronger and way more reliable, even if both bungy's break the AMA still cannot possibly come off. I call it the "RFM Consulting quintuplet reduncy bungy Retention And AMA pulloff Proof system for the betterment of mankind", or RFMCrap for short, ( LOL).
Took all of ten to fifteen minutes to make. You can get the Hobie Spectra string at any Hobie dealer or ACK for about $.30 cents a foot ( I use the stuff for everything ( tie all knots with cinch knots), plus most of us have this type of line just laying around.
I got the 1/4" marine shock cord at West Marine (not expensive), don't use cheap bungy cord from places like Walmart, it doesn't hold up very long. Only use black shock cord, it's impervious to the sun.
EDIT:
Of course if that's not what your doing (never mind), it didn't dawn on me that you might not be making double bungy mod until after I wrote all this crap.

Hope this helps
Bob

fusioneng:

Very interesting.

the leading bundgee has an extra loop of line, different from the rear. Why is it different and how was it Looped and tied? So you don't attach the bundgee's at all, just the spectra loops? Thanks in advance

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That extra loop makes it possible to stand on your AMA's. Once the bungy stretches an inch or two it pulls tight and prevents the bungy from over stretching (works just like your rudder up/down line). That grey spectra string is 700 lb test so conceivably with one on the front AMA and one on the back (1400 lbs test) you could bring your pet horse along and have him sit on the AMA (lol). Actually I typically have snorkelers sit on the AMA's to put their fins on. In my opinion if you have an AMA fall out of one socket (which we have had happen) it does a lot of damage very quickly, where eithe the AMA pokes a hole in the aka pocket, or twists the remaining aka brace, especially someone large is riding on the tramp at the time (we have had this happen to us). It's mostly the rear aka brace that falls out. Ours came out hitting a boat wake with a person riding on the tramp, the stock bungy did not break. Actually this would happen to us quite often until we fixed the problem. Think about it if you were to hit something hard enough to snap or pull out both bungys it's going to take out one or both aka bars anyway. Those tubes stuck into the AMA's are the corner stones of the truss structure, which remains in tact even if an aka sheer pin breaks (the truss folds) and little damage occurs. But if you remove one key element (corner stone), great damage occurs quickly.
So bottom line is if you can keep the four pivot points in tact, even if struck and the nylon sheer brace breaks, the truss remains strong. Adding a simple stretch line from the bow to the steel cleat on the center of the AMA prevents the truss from folding too far and also prevents the aka bars from slipping out of their pockets (at the hull) in the event where you actually sheer a nylon sheer brace (keeps you from capsizing).
We have broken many sheer pins (more than dozens), it generally occurs when your barreling along at 15-20 mph and a sudden gust comes up and tha AMA buries, or you hit a boat wake or wave at that speed it generally snaps the nylon sheer bolt (pretty much every time). Of course without the stretch line or HAKA's you capsize because the AMA folds in.... And you get very wet. With the safety line you just stop, furl the sail, replace the broken pin and you off on your merry way. But of one of those posts comes out you will be pedaling back to shore with the broken AMA and cross bars sittin on the other tramp on your new proa.
I'm just sayin
Bob

Thank Fusioneng:

I am not a sailor, so SIMPLE STRETCH LINE has me a bit intimidated. Is this another spectra line, or something else. I have had an ama pin collapse and the boat flipped, but we were in a surf line and I was already flipped out of the boat when the last wave in the set lifted the back of the boat while the bow was grounded on the steep beach. LOTs of lessons learned that day! There is a video of something like what happened to me by another TI owner. I had BOB's spray skirts on and when the ama pin broke, the ama was pushed forward, and torn the crap out the skirt line.

we lucky there was no damage to the mast or sail in the short time the boat lulled in the surf.

I promise, last question on this topic, what is a stretch line, how constructed and material? And thank you for sharing. I really liked the double bungee solution but my DIY skills are not well developed and I couldn't drill the holes centered enough to complete the job. This looks like a doable alternative for me.

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Clintvava:
If you watch the video below you can see the 1/4" nylon stretchy rope connected from the bow of the boat to the metal cleat on the center of the AMA. What that rope does is prevent the AMA from folding back too far so the boat can't capsize if and when the sheer pin breaks (it still folds in a little, (like a big rubber band)).

[youtube2]https://www.youtube.com/watch?v=2BcdE0137Xk[/youtube2]
https://www.youtube.com/watch?v=2BcdE0137Xk

The other fix (the quadruple bungy fix) doesn't require any tools of any kind and can be done in about 5 minutes. Basically what you do is remove the two black screw in plugs on the AMA (they just screw in, and you can remove them with a needle nose pliers). Arfter removing the black plugs remove the factory bungy by clipping one end off and slip it out thru the hole in the fitting. Next you take some fairly good marine quality 1/4" dia bungy cord (I got mine at west marine, you will need about 3 ft of it). Make sure you get the black stuff (not colored), (the black color is impervious to the sun). Next you cut a piece (around 8-9 inches long) and run each end thru the plug, next tie a knot on each end of the bungy and pull each knot tight. Now you just jam the knots into the open round area on the bottom of the plug then just screw the plugs back into the boat, trimming the excess with scizzors. You will want the loops to be around 3 inches long (as seen in the picture) when your done. On one of the plugs, before jamming the knots in you just wrap some spectra string in and around the knots so it can't work it's way back out, then jam the knots into the plug.
Now using cinch knots just tie little pieces of the spectra string onto the loops, making the knots and string long enough to hold the AMA on securely enough so the ama doesn't drop down by it's own weight with that single loop holding the AMA (I would guess around 12-14 lbs pull force each loop, I suppose you could use a fish scale to measure the pull force if you want to get fancy, really no need though). Just adjust the length of the spectra string to get the desired tension. Make sure it's easy enough to pull the loops up and over the fitting when assembling the AMA's (too much tension makes it a pain to assemble and doesn't gain you anything). Once all done and the AMA is all assembled, just tie that extra piece of string onto one of the spectra loops so the max travel the AMA can drop down is only one or two inches, then the spectra pulls tight, it would take an additional 700 lbs of force (snapping the string) to pull the AMA off.
Actually that same little piece of spectra string could be added to any of the double bungy mods that have been posted ( I like Tom Kirkmans double bungy mod also)
[youtube2]https://www.youtube.com/watch?v=f_vzcxaP66w[/youtube2]
https://www.youtube.com/watch?v=f_vzcxaP66w
Here is his thread viewtopic.php?f=71&t=46952&hilit=double&start=15

Here is another thread with a variation on Toms idea (actually this is what I thought the OP was asking about on the original post until I re-read it afterward....)
viewtopic.php?f=70&t=49980&p=228931&hilit=double+bungee#p228931

As I understand it, starting in 2015 all the TI's will have double bungy's on them ( Hobie listens to us).

Hope this helps
Bob

]Fusioneng (Bob):

Bought the supplies and am going to try it on one point. Tying the loop the best distance is challenging rigging, I can appreciate the work you did to make this work. I can also see why Hobie designed with bungees. Very KISS. Thanks for the detailed and thorough instructions. when I get it so I am satisfied, I will post a picture. The links are most helpful.

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https://www.youtube.com/user/mastery415/videos

I think I am going to add a spectra limiter to the factory bungee set up too

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Actually it never dawned on me to do that. If there is nothing wrong with the original bungys why replace them. Just unscrew one of the caps, wrap the spectra around it a couple times then re-assemble. Adjust the string so the AMA can only drop an inch or two and your done. Not a bad idea, my bungys were worn out and needed to be replaced anyway (they only seem to last a couple years) so that's why I replaced them.
Bob

Thanks Bob for your Help,

I gave it try and this is how it turned out. I ended up with a couple of extra loops when the bungee stretches ( )


Spectra Bridle (1)

This is the spectra Insurance on the unchanged bungee....or Bridle Insurance Spectra Bridle (2)

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Fusioneng:

Thanks for the clever double-bungee mod. I borrowed heavily from your design to rid my boat from the dreaded “dropping ama syndrome”. Tested it out this week and it was rock solid.

I did deviate a little from your photos. The main reason for this is I used 5/16” Novatec shock cord from Annapolis Performance Sailing which has a particularly strong pull. There was insufficient space in the bungee screw-in fitting for two knots, so pad eye fittings were used instead. A length of bungee was made with two knots 8-1/2” apart. The ends were burned and shrunk wrapped. Line was inserted through the pad eye and then around the middle of the length of bungee and then back out the pad eye. As the line is pulled, it draws the bungee through the pad eye, forming the loop. 550 lb test paracord instead of spectra line. This is softer and has a larger diameter than spectra and seems to be gentler on the bungee loop where it is attached. Paracord does have a 30% elongation specification, but that doesn’t seem to be a factor with the low force required to hold the ama. Time will tell if the paracord was a good choice. Four “safety tethers” were used – one per aka arm. One neat bonus from using pad eyes in that a couple of spare bungee assemblies can be carried on the boat that can easily be installed on the water without tools should a bungee loop fail in action.

Another nice feature of fusioneng’s mod is that a cushy easy-on-the-fingers loop of line can be used to pull on the bungee when hooking up to the aka. This leaves the attachment line loop with slack and it is a snap to place it over the aka “mushroom”. Once attached, pull out the line and repeat on the next bungee. No more pinched fingers.

Here is an alternative to tying knots or using hogrings in bungees. I use this method all over the TI.

I use zip ties! I know I know, they come loose if you pull hard enough. Well not with my method..

Typically, I would use two zip-ties, spaced about an inch apart. I then pull them really tight, using a pair of multi-grip pliers. But then I add ANOTHER ziptie at ninety degrees around one of them, inside the two bungee cords. This one, when pulled tight forces the bungee into a shape that makes it impossible to undo.

Alright, I admit I haven't tried using my car to break the join, but I have been unable to break one down using all my strength.

Worth trying!

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Tony Stott
2012 Tandem Island "SIC EM" with Hobie spinnaker