THE HAKA BENCH SEAT - AN ALTERNATIVE TO TRAMPS

I don’t think we have ever disagreed on anything Keith but I have to disagree with your comments about ‘Steel’. ( I have worked most of my life in ‘Steel City’ Newcastle so I must admit I am a bit bias with this superior product ). Steel is the only way to go ! It’s not just the type of material that makes an item heavy, it’s also the shape. If you can reduce the weight by adding holes and slots, and also shape the item to still retain the strength, you’re on a winner. ( go back to page 21 for basic build details )



1. Cost - $49
2. Build time - 2 hours
3. Strength - Ample. Believe it or not, this is only 1mm thick steel section. Just shows how important the profile shape is in obtaining optimal strength.
4. Corrosion Resistance - Excellent. Zinc coated. 2 years and not a sign of corrosion. I don’t even wash it after use anymore.
5. Weight - Can you hold your Haka out at arms length ? (for the record 4.5kg)
6. Aesthetics - oh well, 5 out of 6 ain’t bad. I must admit it's not as sexy as timber.

" STEEL " Is there a cheaper, stronger, lighter, uglier material out there ?

_________________


Don't take life too seriously................it ain't permanent.

OK - Ditto to everything Russ just posted...

I would never argue with Russ, but I must point out that zinc-coated (galvanized) steel is a different animal than the simple "steel" that I was talking about. Maybe the Hobie-branded hakas will be galvanized steel, but I doubt it. Aesthetics does have value, especially when you are marketing something. Still, if you could stamp that "steel" haka out, Russ, I think there would be a market for it until something better comes along.

Maybe K-P-D's idea for a new thread entitled something like "Who can build the best hakas at 5 kg or less?" has some merit?

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

Blasphemy. If it can be done, post it here.

Better we ALL lose our great ideas in the SAME place.

My wife doesn't seem to have a problem with arguing Keith.

It is worth noting though that zinc coated or galvanised cable tray is a bit of a lucky dip. Some coatings are good, others don't seem to last long at all. I suppose boat trailers fall into the same category.

Timber certainly does look the part and wins the aesthetics hands down.

_________________


Don't take life too seriously................it ain't permanent.

PLEASE MR HOBIE! Put everyone out of their misery by making rotomolded hakas. Keep the weight down by having many "scuppers" linking top to bottom surfaces (think a la spineboards).

Heck you could even enter the spineboard business to leverage your investment!

Go on, you know you want to!

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

My idea of using Marine Plywood laminated with aluminum sheet would make a strong panel but the continuous wet environment makes me nervous that the ply would fail.

Just thinking out loud here: Why not aluminum diamond plate welded to an aluminum tubing or angle frame ? Or skip the frame and form the edges of the diamond plate to provide the stiffness. I'm thinking about how aluminum truck boxes are fabricated.
It would be light weight, non-slip, corrosion free. It can be plasma or water jet cut to any desired shape with openings for lashing stuff down or install hardware attachment points on it.

I know I Know, make one and report back.

Chris

Three dimensional printing.

Boom.


-RH

_________________
2013 Tandem Island "Victory Lane"
Oahu, Hawaii
www.rotorheadsblog.blogspot.com

Ditto!

Good points Rusty!
Cheaper stronger and uglier? Probably not. (Actually since you nikscali'd your haka it doesn't look too bad!)
Lighter, better looking and more corrosion resistant? Definitely ...powder coated aluminium or carbon fibre!



Tony,
I'm not convinced that PE spineboard type haka are the way to go. Being rotomolded, they will be heavier/bulkier than other materials.
If Hobie were to make a haka I'd like to see it along the lines of their cat wing seats:



A school/park bench extrusion comes close, but designed for a 1.8m span they are still a bit heavy. 2m x 25cm = 5kg

Properly designed (like Slaughter mentioned above) to fit the 1.4m aka span, with hole/slots etc, to lessen weight and reduce windage an alloy/CF seat would definitely be under the magic 3kg.

Thomas,
Back on P67 I detailed my V3 haka. The framework for these 2m x 30cm powder coated alloy, that are strong enough to stand on, weighs 2.97kg. I added another 3kg in padded vinyl seats that I already had, but if I was really weight conscious I could have used a single layer of perforated foam and an extra centre spine for support. This would make for a reasonably comfortable haka well under 4kg in weight.

Finally got my "standard" wood hakas out. They worked great. By using a bungie under the tramps tensioned to a line/cleat aft on the haka I can rig it with the tramps. I know lots of folks are anti-tramps but I like having them. My guess is about 15-17 lbs/7kg for the pair and solid enough for myself (probably a bit flimsy for two adults).

_________________
2013 Tandem Island "Victory Lane"
Oahu, Hawaii
www.rotorheadsblog.blogspot.com

Doin it Hawaiian Style! A 3-slat version to keep the weight down. I like it. Good choice with the tramps.

Here's the "classic".


You tried sitting out there from the rear seat?

I agree with you on the tramps Rotorhead. I wouldn't be without them.
Your haka look great but why so far out?
Either I'm too heavy or the winds here are too light but if I placed my haka that far out and sat on them the ama would be submerged, unless it was over 20 knots!
I find the ideal placement for most conditions to be just out from the aka brace bar.

Nohuhu, I think I used your pics for my design, everything clean and rounded off so nothing catches or snags. The wind was very light so we only got out on them a short while, but they worked fine. Didn't sit all the way aft; not sure if the bungie tension would hold the for'd end down.

Stringy, I need to move/remove my railblaza mounts on the akas in order to move the haka inboard. I'll get around to it but most of the time there is more than enough wind to hike out there.

For sheet control, is everyone using the little harken swiveling fairlead camcleat (Harken Swivel Bullseye w/#150 Cam-Matic Cam Cleat)? I haven't fitted that yet, can I use the same hardware as the existing cleat?
-RH

_________________
2013 Tandem Island "Victory Lane"
Oahu, Hawaii
www.rotorheadsblog.blogspot.com