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tiki 46 boat building movies
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i posted here some movies (links) from the time we build our tiki46 wharram catamaran.
it took us 2 years and 6 month to finish the boat.
please visite our web page www.wharramsailing.com for more infos.
please do not forget to donate some $ to budgetboater. to set up all this is a lot of work and will make your job maybe easier... have fun
cheers hans "wakataitea"
Website: http://wharramsailing.com
Members: 18
Latest Activity: Dec 9, 2023
Building a boat nr1 diashow from nicedaymovie on Vimeo.
tiki 46, building the rudder blades from nicedaymovie on Vimeo.
building the hatches for a tiki 46 from nicedaymovie on Vimeo.
wharram tiki 46, building the crossbeams from nicedaymovie on Vimeo.
tiki 46 long shaft propeller system on wakataitea from nicedaymovie on Vimeo.
http://wharrambuilders.ning.com/photo/albums/wakataitea-tiki46-long-shaft-system
or read this...
Dear Hans! Let me be the first to thank you for giving us the details of your - over 25000 miles - tried and true, diesel/long shaft design! The pictures answer most of the questions Wharram" liebhaber" have been mulling over since way back in the Dec. 1976 pages of the Sailorman.
You are rigidly mounting the engine cum Hurth (@ 5 degrees) to the same steel frame that the pillow block is bolted to; thus no alignment problems. Then a single U-joint takes up all the angle (15degrees) and thrust (about 1.4kN, or 315 ft lbs, I estimate?) from your 4.5m( ca 15 ft) long solid ss 7/8"(?) keyed shaft (off the shelf, incl. propeller taper?) terminating in a (appears to be a ?folding? prop(can't be, right? I had estimated about a 15" 3-bladed prop (of unestablished pitch) for a similar sized diesel..) .I also noticed with pleasure the provision of a PTO(power take off) pulley betw the tranny adaptor plate and the pillow block! From the other pics it appears you haven't found a need for using this PTO?
I also notice that you cool the upper, (cutaway?) Cutlass bearing betw shaft and tube via the exhaust manifold water jacket water - cool! And this whole assembly doesn't vibrate inefficiently at a shaft rpm of ca. 1000!
I don't know yet what Chris Bretter, etc. are thinking, but I want to tell you: you made my day!, Because up until yesterday I thought I was going to have to create one of those' Thai long-tail' assemblies, and I didn't relish the challenge of a pivoting axis for the whole power plant...
Concerning the suspension of the long shaft, the lower strut is clear to me, but I'm not sure how the upper one works in the geometry, but that becomes clear once one is putting it all together,,,
Where are you now? Is there some way I could mail you a little present? dennis schneider
Permalink Reply by Rusty Gesner on
Hans, Many thanks for the very enlightening pictures. I'm hoping to acquire a Tiki 46 in one to three years, and want to repower it with a couple of 20HP +/- longshaft drives. You also mentioned you had posted more info on your blog, but I can't find it either on this site or your wharramsailing site.
Thanks - Rusty
Permalink Reply by wakataitea on
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hallo mdennis,
i am in mayotte (indian ocean ) in the moment. thanks for offering a present. that nice. i will be probley to fare away that you can send me a cold beer, so i wish that you build your self a nice long tail system and go cruising... we have the beer when we meet eath other.
i do not understand all of your posting because you English is a bit to professional... i see you have some questions. so i will explain my system.
first:
between the CV drive and the gearbox is a bull because i thought that i will use this system as a water generator to one day. but will not do it because i have a lot solar power.
i take the cooling water for the engine thru the alu pipe under the shaft. it works really good and because when i lift up the engine, the hose makes a bow and the water stays inside. this is important. it helps to suck the water fast when i start the engine.
the water pump is the regular one which is on my kubota (beta marine) motor. so no extra one...
the 4,5 meter shaft has every 80cm a cutlass bearing made out of a special PE plastic which can handle 1200rpm with out any lubrication. but as you saw, i let the exhaust water flood into the shaft to lubricate everything. i can see although if there is water coming or not... i have a 20mm hole in the deck thru where i can see / control the water flow.
my shaft is by the way a one inch shaft i alu pipe around i guess is 50mm. i pull the shaft sidewards up because i wanted a SS pipe holding the shaft system down going forward and back ward. two ropes hold the shaft in position. one robe is fitted on a fixed length and the other has a block and tukle to pull it tied. so i drop the shaft and just pull the other rope to lock the system. pulling up the shaft, i just relaese the lock and pull on the rope wich is fixed in it length. takes all a second to do... i do have to drop the shaft every time to run the engine because of the seawater cooling.
on the picture you see a folding propeller. i got this on for free and used it for a year. of course you do not need this but it was handy to because this long shaft systems are exposed to everything floating in the water. when i saw a rope, pastic bag or drift wood, i just take out the gear and the prop floods together. nothing get stocked.. or hang on it....
i use now a 2 blade fixed 14 inch prop. this one performs better and bushes the boat in flat water (no wind) full power at 7-8 knots. i motor longtime easy around 4-5 knots... i like this 2 blade prop because it is gentle on the system when your drop the shaft in the water under sails /speed. imagine the pull it has if you throw a 5liter bucket in the water with 4-5knot of speed. this pulls quite hard... a 3 blade prob will pull more too.
i attached a SS disk (20mm thick) on the shaft. if something brakes or the shaft moves out of the CV. this disk will stop it and i will not loss the shaft. i heard from other wharram sailors that they lost the shaft.
i am thinking of building a protection around the prop but could not figure out a intelligent way. it will catch allthow stuff and create more drag. we watch out every time carefully whats in from of us. special in habours and rivers...
if a catch something, i put in reverse and most time it blows the stuff out. worst case i have to stop the engine and pull up the shaft and clean...
we do not have vibration on the shaft. only the engine vibrates in certain rpm. because i fixed it on wooden blocks and no robber. some engineer told me it is better because the ball bearing holding the shaft down is solid fixed too. i grease/oil the CV join every 20 hours. it has no sign of wear. looks like it will last for ever....
because the engine is mounted on or between the 19mm ply deck, it is quite noisy. we do not motor a lot because of this. the box around the motor is 5mm ply with some foam. this is like a "guitar body" and amplifier the noise maybe...
ok, i hope all is clear now... have fun
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.... i forgot.
make sure that the prop is min. 70cm under water. otherwise it will cavitate a lot. i started with a 3.5m long shaft added one meter one year after. 4.1m incl. tapping...
i build a kind of triangle (kraefte dreieck) which holds the shaft up close to the engine . you can see it on one pic but not very clear. the blue rope with the rigging screw helps too. i will make a foto to show it more clear.
Permalink Reply by dennis schneider on
Lieber Hans Thanks for your prompt reply; I learned so much!
For example, I had read that my Hurth HBW 10 - 2R would overheat without an added- on oil cooler, according to the main Hurth repair service here in the US. But you report no problem: good.
And, I had thought that if I lengthen the propeller shaft by 1.5m, for the same reason as you stated (cavitation) that it might cause the shaft to vibrate more. But, you say no problem there too. I assume you joined the two shaft segments together with a standard 6-bolt, split shaft coupling?
And, you solved the problem of the propeller vibrating around down there on a single fixed metal strut by your use of a rope to pull up/lower the whole long-shaft/propeller assembly?
Also, I had read that the plastic sleeve bearings inside the alu tube should be machined from 'polyacetyl, or high molecular weight polyethylene, such as brand "Vesconite" (Australian)...I read that in Thailand they just use hardwood blocks for sleeves, and grease fittings.
I, too, find the noise at 2800 rpms deafening, so am working on a double- walled motor housing, which will be more complicated, because of the air-cooled engine(Deutz). I plan on 300 watts of solar panels. Are you using wind generation?
I looked up Malotte,( which became an official 'departement' of France 3 yrs ago) and wonder if you, as a German(or Austrian?) citizen of the EU, have the same (work/medical) rights as a French citizen, because Malotte is becoming a goal for refugees, and Malotte is deporting thousands of illegal refugees yearly, and 97% of the population is Muslum? I understand the Cormoran Islands are unhappy with Malotte"s independence? What's it like being an expat live-aboard couple there. Are you using French or English? What about theft and violence?
Wishing you two the best, Dennis and Inge(Deutsche aus Boppard am Rhein).
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i am form duisburg am rhein.... left 1999 old germany
mayotte is a real shithole.... only the underwater world is great. everything above sea level is horble.... dirty, expensive and really nothing interesting on land. there is not one building which looks nice... to many people, cars etc... as a german, i can use the medical system etc... i do not speak french, my wife does, the communication is very difficult. there is only one nice thing here. the ACHM sailing club. very helpful, friendly etc...http://www.sailingadventureworldwide.com/index_htm_files/ACHM/index...
so, back to the shaft:
i found a very good welder who welded 1m SS schaft onto my existing shaft... nice job. the SS tube (single fixed metal strut) which is holding the system down is 1,2m away from the prop. so the prop is 1,2m free "swinging"
i will send you a picture soon...
you are right, you can use hardwood or plastic as a bearing... do not make then to tight. give tollerance because the wood will explent when wet and you do not want friction. i machined them like a regular cuttless bearing. (with little holes around it) i have only at the end of the shaft a real cuttless marine bearing...
the single fixed metal strut is connected to the tube (i used 18mm SS shaft) which comes from the engine. so the shaft "housingtube", the vertical strut and the horizontal tube are fix togeather to a triangle. this makes the whole system stiff. the blue rope is supporting only a little from the top.
air cooled engine: good idea but you still can make a wet exhaust to get the noise down... and you can lubricate the shaft in the alu tube...
my hurth gearbox has no cooling... no oil or so... it is air cooled
because of our crab claw sail we have no space for a wind generator. only solar, 450 watt.
have fun
hans
Permalink Reply by Meinhard Koch on
Hallo Hans,hallo Dennis!
Keep on mailing and exchanging experiencis here public in the forum! Bitte weiter so!
A wonderful source of informations!
Meinhard
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nach dem moto "German engineering..." ;)
Hans,
When you say "make sure that the prop is min. 70cm under water. otherwise it will cavitate a lot" are you measuring from the waterline to the centerline of the prop or to the top edge of the prop diameter?
Thanks - Rusty
Hans, another question:
Do you experience any vibration due to the uneven loading caused by your fairly steep shaft angle (I think you said it totalled 20 degrees.) And do you think a longer shaft with a smaller angle would reduce the need for such a great depth to reduce cavitation.
With no experience in this yet, I am only theorizing, with reference to this article regarding shaft angle, efficiency loss, and uneven blade loading that can cause vibration and/or cavitation:
http://www.ricepropulsion.com/TNLS/Shaft_Angles.htm
Thanks again - Rusty
Rusty Gesner said:Hans,
When you say "make sure that the prop is min. 70cm under water. otherwise it will cavitate a lot" are you measuring from the waterline to the centerline of the prop or to the top edge of the prop diameter?
Thanks - Rusty
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from the waterline to the tip of the blade.
a 4.5m long shaft i allready a monster. i would not make it longer. our shaft is in the side the boat. if you make it longer, you have to move the otor more forward. it all depends on how high the motor is above the water too. our tiki 46 has a lot free board under the boat...
20degree is the recommended limit for the CV. in real, our shaft has maybe 25-30 degree into the water... but i am not sure about this.. that's all fine.
we just had a nightmare experience yesterday here in mayotte on the anchorage. we where on a mooring close to the reff. 25-30 knot of wind blowing us the the reff. the mooring was fine but the waves got higher and higher. our bow dove into the water few times. so we took of. full power forward. the prop came few times our of the water in the valley of the waves... but the boat made forward... i was a bit shitting in my pants. on the right side the riff and on the left boats on the mooring... strait forward into the waves... the boat was badly hobby horsing.
the fact that the prop comes out of the water and starts bushing again does not help the boat going forward. so it was very slow and hard on the material. when we turned left , the waves came form the side and to not lift the boat anymore to make the prop cavitate. all was fine then...
so, keep min 70cm draft for the prop. (if the prop is at the end of the boat) if the prop is in the middle. it will not get lifted so much...
a shaft longer then 4.5m gets very haevy too. remember , we have a 25mm shaft on a 14 inch prop and 28hp. if you motor is bigger, you will have a bigger and more haevy shaft.
one thing mor. we do lift the shaft sidewards out of the water. because it would block the platform on the back otherwise.
have fun.
hans
ps: i looked at the www page. sound all good and not good for me but i got want i got and it works for me... that's important... theory and practice. smile
Hi Hans und Isabelle! What a coincidence: yesterday I was thinking about how long you've already been in Mayotte - without any bad incidents...Since you now describe it as "such a shithole", I was becoming apprehensive about your situation. Now this event with the high waves and reef isn't untypical, and you have prepared for it, so you mastered the crisis like "the German engineer" that you (vermuetlich) are... Like you state, the central concern is to have the propeller deep enough to be able to manoever when hobbyhorsing in steep waves.
This issue has caused me to design my 46'er with a Brown Searunner double chine unterwater profile: d.h.:a lot of buoyancy in the bow and stern, to diminish hobbyhorsing. Concomitant with that goes the depth of the propeller and its proximity to the stern vs the centerline. My design has a lot of displacement (6 tons @ 18 inches draft), because it is for living aboard, not long passage-making, so I can comfortably have the powerplant forward of the centerline (close to the 2nd beam)., thus the propeller will be under the 4th beam @ angle of 15 degrees, which is the max. incline recommended by that great reference book on propellers by Dave Gerr "Propeller Handbook".
Your description of yesterday brought back to mind our 1979-81 travels on our Tangaroa Mk 1: using a Chrysler Sailor 10 hp long shaft on the 4th beam, we were being push astern by wind and waves in a little Belgian harbor; only just made it, having put periscope air tubes on top of the outboard Haube, (like those WW II subs), which kept the motor from drowning.. Othertimes, we relied on the cutter ketch rig to allow us to tack out of similar situations(you did not have that option, I know). freundlichste Gruesse von Dennis und Inge
Thanks Hans! Your video shows how efficiently your design works. Now we all owe your royalties, as soon as our own rigs are functional! seriously! On Boatdesign.net forums there has been a question of whether , by transferring the axial load from the U-joint via the pillow block (weiss nicht, wie dat Ding geheissen soll?) to the marine transmission the pillow block might be damaged, since it isn't designed for anything but rotary loading. .. Your experience would mean that we shouldn't have to worry about that after all...danke sehr, dennis
Hans,
Thanks for the Illuminating video.
Has anyone investigated the use of Lignum-Vitae Wood for water lubricated bearings?
Bearings have lasted for decades in hydro turbine generator plants.
http://lignum-vitae-bearings.com/tag/pillow-block-bearings/
http://www.woodcraft.com/Product/2083909/44709/Lignum-Vitae-3-x-3-x...
I'm investigating, plan to do some tests at some point. It's has self-lubricating properties due to oily resins which may make up 1/4 of the wood's dry weight, and water further enhances the slipperiness of the resins.
Heartwood of Genuine Lignum Vitae, also known as Guaiacum officinale, NOT Argentine Lignum Vitae (Bulnesia Sarmientoi)
Permalink Reply by Armin Foell on
Das Ding heißt flexible coupling!
Flexible couplings are normally not designed to carry axial loads. But it depends on the particular version.
If the used flexible coupling does not allow axial loads then the only option is to build in an additional thrust bearing (Drucklager) has to be used. The question is, do you really need a flexible coupling? If the Universal joint is aligned properly to the reverse gear (Wendegetriebe) and the axes are not skew-wiffed (or warped)(Windschief in German), it should be o.k. without one.
The additional thrust bearing can be a simple but strong ball bearing (Rillenkugellager) It does not necessarily have to be a roller bearing (Walzenlager) or even a taper rollerbearing (Kegelrollenlager).
The thrust bearing has to be supported by a kind of clew which is firmly connected to the boat.
I hope this helps.
Always a hand of water beneath your keel as we use to say in Germany :-) means: Fair winds and following seas
Best regards, Armin
Replying to my own post...
Well, maybe not, as true Lignum-Vitae is endangered and banned from international trade.
Rusty Gesner said:Hans,
Thanks for the Illuminating video.
Has anyone investigated the use of Lignum-Vitae Wood for water lubricated bearings?
Bearings have lasted for decades in hydro turbine generator plants.
http://lignum-vitae-bearings.com/tag/pillow-block-bearings/
http://www.woodcraft.com/Product/2083909/44709/Lignum-Vitae-3-x-3-x...
I'm investigating, plan to do some tests at some point. It's has self-lubricating properties due to oily resins which may make up 1/4 of the wood's dry weight, and water further enhances the slipperiness of the resins.
Heartwood of Genuine Lignum Vitae, also known as Guaiacum officinale, NOT Argentine Lignum Vitae (Bulnesia Sarmientoi)
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teak wood has oil inside too. so you could use this one too. very important is , that the wood does not ex bent ( aufquillen)to much when getting wet... guys, make you life easy and take a plastik that can handle it... ....
my CV join has roller bearings inside... (nadelnager...) the data sheet says that in can /could handle up to 450kg trust...
armin is right. CV joins are not made to take trust but this does not mean that they can not do it... if you handle your instalation with care... it will last. my one last now since 5 years... of course, if you but a prop on the shaft which is anyway way to big for your engine, then you stress the CV join even more...
as i mentioned, my engine has 28hp and a 14 inch 2 blade prop...
armin wrote:.... If the used flexible coupling does not allow axial loads then the only option is to build in an additional thrust bearing (Drucklager) has to be used. The question is, do you really need a flexible coupling?.... that's right BUT....
a mirine gearbox is often made to have trust to look in right... it depend of the gearbox of course... my hurth gearbox need this trust that the clutch packet inside can work proper... so if i would use this trust bearing, my gearbox would not work and would slip....
DO NOT FORGET, THAT YOU WILL SAIL MORE THEN YOU MOTOR BECAUSE A WHARRAM DOES THIS BEST... and you are operating a plesure boat not a tuck boat, that needs to bush hard...
ok, that it for today...
PS: if some one likes my statement about the long shaft so much. please donate some dollar to buchetboater.... i/we can not effort it in the moment...
thanks a lot...
hans
and so on.....
sailing wakataitea from nicedaymovie on Vimeo.
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Comment by Demi & Dirk on February 10, 2014 at 8:26am
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Thank You Hans! Very helpful for us. Fair winds, Dirk
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