THE HAKA BENCH SEAT - AN ALTERNATIVE TO TRAMPS

Now you have!

I'm terrible with taking pics -- just ask any of NCKA...

And those paddle clips are strong enough? They look like they could fail easily (looks can be deceiving)

stevo- thanks. No complaints about the Picts.

Now that I am happy, you can go ice that foot.

CC, I forgot to suggest using a center punch to make the clean holes, (such as a piece of chrome plumbing pipe).

You probably have sharp woodworking tools around that would work fine.

They haven't failed in more than a year. I used to have only one on the front,
worked fine.
There isn't much rearward pressure on them- even when your are hopping around. They're plenty strong for the forces on 'em.

Coach, my experience is that in 1-2 ft chop, as my boat goes over the waves there is tremendous wave pressure coming up from beneath the haka--easily sufficient to pop those paddle clips off the aka, even when secured by a bungee. Have you had that happen? And, if it does, what happens subsequently?

Keith

_________________
2015 AI 2, 2014 Tandem

"Any intelligent fool can make things bigger and more complex ... It takes a touch of genius and a lot of courage to move in the opposite direction." A. Einstein

"Less is more" Anon

leelanaux,
I'm looking forward to your finished design. The prototype is a work of art!
The tube clips are very strong and made of UV stabilised nylon, available from boat shops/chandlery's. I've used them in lots of applications and have never had one fail. The 38mm clips fit the aka well.





Answering some of the other queries:
The ladder haka cantilever about 75cm over the aft aka and that's where I usually sit. The forward hooks have worked well
with preventing uplift and as there is a bit of adjustment room with the hooks the haka can be positioned any where on the aka or crossbar (for a camping platform). If the winds are light I'll place the haka closer in and if the wind picks up I'll move them further out. All easily done on the water.

I've never had an issue with the haka popping up on either AI or TI. I always use tramps with mine which may offer some protection from wave action.

Good point though. I could see that happening, riding swells downwind, in surf zones, or wake. If you leash them, you should be OK.

If anyone wants to consider a softer, rubber mount clip, these come in 1.5" ID sizes. Won't ruin your paint job. From Baja Edd http://www.thesundeckonline.com/Rubber3.htm

For the front Aka:


For the rear:



Also the US sized plastic clips:
http://www.thesundeckonline.com/PlasticClips12.htm

All my missing "Haka" thread photos and important references have been recovered and updated, as of today.

Would not surprise me to see this historic discussion go another 60 pages.

Mahalo everyone!

Has anyone used rectangular box-section aluminium for their Hakas?

The sort of stuff that's used for bus-stop benches and similar seats seems ideal:



Apart from the cost, are there any disadvantages to using ally over wood?

Cheers,

Mike.

I searched them out, in the US, and they were expensive, heavy and were tied to heavy steel subframes. Too likely to rust.

Closest thing I found was athletic bleacher sections, possibly ready to accept an aluminum base. All made to heavy, kid-proof, lawyer-proof specs though. So I started looking for lighter weight solutions. Polywoods, ladders, metal grates, shelving, etc.

If you know the metal working trade, you may have some better leads. Please pass them along.

I keep fantasizing that I'll walk into Home Depot and there will be an uber cheap china-made picnic bench there with 2 perfect Hakas on it (in red). I'll take the R2A box home for $49.95 and I won't even have to assemble the kit. Just strap them on the AI and go. (Void where prohibited --Supermodels not included).

Hi,

I wouldn't consider a pre-made bench, for the reasons you mentioned...

The aluminium stock is pretty easy to get hold of in a huge variety of shapes, so I'm currently
trying to figure-out the best size to use. Something between 60-75mm x 16-25mm is what I'm
thinking about. A 6.5m length comes in between $90-100, which should be enough for one decent
haka.

The weight of the stuff seems to be around 1kg/m - how does that compare to some of the timber
other people have used?

Cheers,

Mike.

Repco sell a pair of aluminium ramps which are about 1.8M long and capable of 300+kg load, for somewhere in the low $200s. These are about 30cm wide if I recall, and while they resemble ladders, it wouldn't be difficult to make them comfortable.

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

Haven't had any issues with them popping- maybe the end chop here in SF and the eastern pacific is too whimpy...LOL.
Even when I only had a single up front I didn't have any issues. It takes a pretty good whack to pop them loose, but hasn't happened yet. I have had plenty of wash over, and even a few surf landings.

Now you've got me thinking I should back them up!

When my haka "popped" off the aka, the chop may have been 2 ft. It happen twice in a 2 mile stretch, and it happened at least one other time. I was on my solo camp trip last year and sailing across Ponce de Leon Bay when the first incident (2) occurred. http://www.hobiecat.com/forums/viewtopic.php?f=70&t=7276&start=255 Also, it was the front haka-aka connection which "popped" off. On my hakas, I have an aluminum angle just in front of the forward aka which prevents the haka from sliding backward. However, if the haka is lifted up enough to "pop" that angle over the aka, then, the haka is in danger of sliding backwards off the aka. My hakas are loaded with gear, maybe 15-20#; so, if the Al angle was lifted up enough to clear the aka and slide backward, the haka could slide off the aka--that would be disastrous, or worse. After the 2 incidents crossing Ponce Bay, I tightened the loop bungee cord, which had been too loose. Here is an image of the underside of my haka.

I'm thinking now, that I should reverse the position of the rear angle. It should be placed immediately in front of the rear aka to prevent rearward slide of the haka. Alternatively, I could simply put 2 small 1.5" angles in front of that rear aka--they would prevent the rearward slide even if the forward angle was popped up. The under-haka wave pressure is strongest in the front aka area and tends to lift the haka and force it backwards. In my experience, there is no tendency of the haka to slide forward. The loop bungee is very convenient and allows "instant" attachment/removal of the haka. The full description of the construction of these hakas is at http://www.hobiecat.com/forums/viewtopic.php?f=70&t=7276&start=240

Keith

_________________
2015 AI 2, 2014 Tandem

"Any intelligent fool can make things bigger and more complex ... It takes a touch of genius and a lot of courage to move in the opposite direction." A. Einstein

"Less is more" Anon