Cruising weight - crossing the safety line

[Tony Nannette Brett]

Our Tiki 46 was born heavy - none of this anticipated lightweight bobbing and bouncing around for our baby! As soon as she was launched it was evident that she was sitting slap dab on her water line. The addition of sails, some equipment, minimal water, fuel & food etc turned the 'nipping the waterline' into a squatting the waterline! 

We've had some input from Hanneke about water lines and safety margins - and she made the excellent suggestion that we also pose the question to the wider Wharram community so that we can all benefit from folks practical based experience.

So please ... all input welcomed. Share your experiences.

What do you sail? What are your loading experiences? How have your boats handled under what sorts of loads in what sort of weather? We're especially interested to hear from Tiki 46 sailors, but thoughts, experiences, input and advice from our wider community so that others can benefit from (what I hope) will be a deluge of wonderfully informative information is welcomed.

Regards,

Nannette & Tony

Boundless Tu.

 

[wakataitea]

we draft now 1.1m on our tiki 46. the water ,the line is still under the clink of the hull. sometimes i have the feeling that our wharram sails better full loaded.... it is  a great boat... a "LAND ROVER" you can do everything with it...

i saw your nice boat  few weeks ago in langkawie. we are in phuket now. would be nice to catch up on day. we will sail down to langkawie in 3 weeks time.

 cheers hans

 

[Tony Nannette Brett]

Thanks for your input Hans - much appreciated. Tony & I aren't on board, but I'm sure Brett (our Son) would welcome your visit and the opportunity to 'talk Wharrams' with you. He's currently making his way from Langkawi to Phuket. Whereabouts in Phuket are you? I assume the best way to contact you is via your website www.wharramsailing.com? 

Cheers Nannette & Tony

[Ann and Neville Clement]

Peace IV is a Tiki 46 and she  has the water line a couple of inches below the chine when  fully loaded for cruising but the water splashes above and causes a scum to form so we are raising the antifouling to an inch above the chine because we are starting to be lazy about cleaning  off the scum. 

Peace was built using marine grade Okume or Gaboon ply which is lighter than the design spec Douglas Fir ply and much lighter than the Meranti ply that I suspect was used to build your boat. 

If I were to build another Tiki 46 (God forbid) I would use alloy masts to save weight.  We are unable to lift, let alone carry, our wooden masts but if they were alloy we could just walk away with them so that shows how much weight you could save right there.

[Tony Nannette Brett]

Thanks Ann & Nev - it's great to have your input. I should clarify that our boat sat just ON the chine at launch, ie well above the design waterline. There's no doubt she's very strong, but unfortunately she is also very heavy.   

We're not able to cast any light regarding the type of ply used, but we agree that it may be Meranti or similar. 

Good suggestion re replacing the wood masts with alloy.

Given your extensive sailing experience and expertise with a Tiki 46, do you have a weight limit or loading guideline that you use for Peace 1V? And any input of how the boat handles fully laden, paticularly in adverse conditions (high winds, big waves)? (You would have read Hans reply re feeling Wakataitea handles better when she's fully loaded).   

Our experience to date is that in high winds and 2+mtr swells, our boat handles like an 18 wheeler truck - powers on through regardless! But fully laden (cruise mode), she's going to be heavier - ie. chine well down in the water rather than on the water. We're obviously seeking any input/thoughts on how a Tiki 46 laden to sit with the chine well down in the water might handle in heavy conditions before we head offshore.

Cheers. Nannette & Tony

[Rory McDougall]

Hi Nannette & Tony,

Interesting discussion. here's my experience - Cookie, my Tiki 21 weighs approx. 800lbs as an empty boat. When loaded with 2 crew, food, water and cruising gear to cross an ocean I have estimated she carries a load of approx. 900-1000lbs. As you can imagine this sinks her waterline by about 5-6inches!! Luckily when I built her I anticipated this and painted very high  antifoul to compensate.

Does this affect the way the boat behaves??? You betcha! I have sailed Cookie rigorously in both empty lightweight mode and fully ocean loaded mode and experience a very different boat.

It seems pretty obvious to state that when empty and sailing on my own Cookie feels flighty and moves to every small wavelet. She is certainly faster through the water, but her motion is impacted by every small wave encountered. I have had the windward hull flying a number of times when going to windward in choppy seas and a 25-28kt wind blowing. Certainly heart-in-mouth and mainsheet-in-hand kind of thing when I was on a day sail and pushing Cookie to see what would happen.

When fully loaded she behaves very differently. You can feel that Cookie is shoving aside much more water as she slices through the waves. She pitches the bows into the tops of waves more often. The windward hull is more solid and heavy to resist waves hitting her side rather than quickly rising over. Going to windward powered up you notice that instead of lifting the windward hull, she starts digging deeper and bigger holes in the sea with the leeward hull. Sometimes the leeward hull is all but buried underneath the wave tops that sluice over the bow - giving a great sign and indicator that it is time to reef and get her back on an even keel. Just like a monohull that sails no faster when steeply heeled - Cookie sailed better when heavily loaded by not sailing too pressed and not digging holes in the ocean!!

It stands to reason that the beams and connections to the hulls will certainly take more strain and loading when the boat is heavily loaded in a seaway. This is why I would advise to use best materials and microfiber fillets for beams rather than skimping as they are pretty much the key structural element of catamarans.

Incidentally on Cookie, I found the point of sail where the beams and hulls move the most is a quartering sea downwind. The windward stern lashings creek for a pastime! Funny enough, thrashing to windward the rigging tension and lateral resistance pressures on the hulls seem to keep the whole structure fairly rigid. With the exception of the occasional leap into thin air and then stuffing only one bow into a wave top. That will certainly cause some racking!! However, by standing on one bow or stern and jumping up & down I can set up a magnificent racking movement of the boat - this is more than I have ever seen Cookie move to any seaway! And I ain't all that heavy....honest!

In summary, Cookie has been a marvellous test bed of the Tiki design. Small enough to throw proportionally big waves and big dynamic loads at the structure. If you build strong then the design will handle the heavy payloads, you may just have to slow down earlier and expect the ride to be a bit wetter. After all, we sailors love getting wet don't we.............??

Cheers, Rory

[wakataitea]

just meet Gunther, the wharram builder from phuket. he build your boat, he told me... he mention your engine system. hydraulic motors in the hull with 2 diesel engines and huge hydraulic oil tanks. this is a lot of weight on top of the cruising stuff.

we have only one beta marine diesel (155kg) (27 hp) and carry only 150 litre of diesel. i guess your engine system must weight 3 times as much.

i can see your boat is quiet heavy on the back...

changing the wooden masts to alu is not a god idea... wood is much stronger and only to carry them around on a boatyard is maybe the wrong way to go ;)
it makes maybe 100kg difference.

i got with my building plans  a sheet which loading lines...

...throw stuff overboard you don't need really. get solar and no heavy generators etc. get a light dinghy and a water maker and only 200l water on board... use only 45m 10mm chain and 40 pounds anchor. get a knidle electronic book reader and get rid of the books. don't carry to much spare parts except you go to a very remote place...

this will save you a bit of weight. try to relocate the weight on you boat. more in the centre and less in the front.

we build in gaboon ply. the difference to maranti was 500kg.
cheers hans

 

[Ann and Neville Clement]

Hi again,

     Our timber merchant said we saved about 1000 pounds over Doug Fir ply when we used gaboon  to build Peace and 2000 pounds over Meranti ply.   I just trusted that he was correct because he uses those figures all the time and he had the total amount of wood we bought in front of him on his computer when he did the figuring for us.  Wharrams do have a suggested plan for how thick a tube you need to use for alloy masts in the Tiki range and Jacques used that for his Tiki 38 which crossed the Atlantic a while back and his masts were super light even though the mast thickness was quite impressive.  He could tell you the weight exactly but Nev and I lifted them easily.  I know masts are not used just for carrying around the boat yard, but I just said that to illustrate that ours were so very heavy we could not lift even one end.  Ours are hollow and were built by Noble Masts in England and the specification was approved by Wharrams.

     Rory's information re his Tiki 21 is priceless and I certainly read everything he writes with great interest because you can use your imagination to figure out what it would mean for a larger Tiki.  Our Tiki 46 is usually full of lots of stuff and we never worry about weight because the basic boat is so light and to be honest we are not int4rested in speed at all and just like to be comfortable, sail safe, and relax at our age.  We certainly would never fly a hull (God forbid!) and we have never had Peace empty enough to know how she would perform lightly loaded.  But I will say she is strong, wonderfully reassuring, and when she is going fast, she seems to make the ocean smoother and the ride more and more gentle.   We have had her in some storms that were too big (Force 10 offshore) and she handled herself perfectly.  I am sure Gunter built you a boat you can trust and enjoy for decades to come.  Stop worrying and start sailing the trips you always dreamed of.  There is forgiveness built in when you follow the plans and Gunter is an experienced builder by this time and Meranti is one of the approved woods you can use.  Take that boat and go have fun with her.  Your dream came true and she is a beauty!  Raise the waterline, raise the anchor, raise the sails - Yippie!

     On Peace, we take a reef when the steering gets heavy and we also have a creak when we go down 4 foot and higher following seas.  The size of our boat makes she steady in almost every condition of wind and seas.  The creak we have is also from the windward stern of the boat with quartering wind and seas and it attracts whales and they never threaten or harm us but are most interesting visitors.  Sei, Right, and other whales visited us almost every day on the trade wind passage from Canaries to Martinique.  They swam all around us and even from starboard stern to port bow underneath the boat many times and then came and "sniffed" around trying to figure things out.  Like curious elephants...  but they were certainly friendly so whatever Peace was saying to them, they took no offense.

     I think Meranti may be stronger than gabboon.  Don't know if that matters, but there is a flip side to everything!  Happy sailing.  Ann and Nev

[Bertrand FERCOT]

Hello Nannette & Tony

Today I washed the bottom of the hulls from my tender and after I took a few photos of the boat.

The boat is completely loaded ready to go with 400l of water, 200l of diesel, anchors, 75 m of 10mm chains, 2 x 20kg anchors, 2 x Beta25 engines with parallel hybrid electric motors (with the shaft, propeller, wires, electronic system about 170kg each one), 600kg of batteries for 48V + 12V systems, 2 masts of 270kg with 2 rigs of 100kg, I added a longer pod but without the central beam, and a hard bimini with 4 solar panels of 240W.

When the boat has been launched, with all the gears, some food, books, tools , spare parts, masts engines etc. her weight was around 9T and now on these photos I estimate her weight at 10T with the water line 3 cm below the chine :

When the parts of the boat have been lifted for the transport I thought to get a lighter weight according my calculations in weighing almost all the pieces during the building. But in fact it's difficult to know all the exact weights of the epoxy, paint, glass cloth, screws, bolts, ropes, gears etc.

Officially the empty weight of a boat is the weight of the boat ready to sail,  without water, diesel, food, crew and all its clothes with books and other personal things and in fact in the Wharram study plans the empty weight of the boat is only the weight of the boat with no engines, no chains and anchors etc, so the real cargo weight is very different. We'll began our cruise at the end of this month and we'll put off a maximum of unnecessary loads ( some books, clothes, tools etc).

The owner of a Pahi63 who was very disappointed with the real cargo capacity of his boat has added foam outside of the hulls to increase its cargo weight!

Happily  the hull lines of the Tikis accept to be overloaded without to change her ability to sail correctly and safely. When we sailed across the Atlantic from Martinique to Brittany aboard our Tiki30 PHA with a lot of cargo on board she sailed very well.

And since the launch of our Tiki 46 we are very satisfied with the motion of the boat in bad weather. So don't be too much worried with your cargo ability, due to the triangular shape of the hull; more the hull is in the water more the cargo per cm will be higher.

Regards

Bertrand and Marie-Helene

[wakataitea]

hey, meet your son brett a few days ago... nice guy... and your boat looks really nice too. interesting is your layout of the interior..

i think, you shut go sailing. in a area with real winds. not Asia.... and then you will understand you boat better...it will move and sail nicely...

no doubt that in some parts you boat is really over build... and to heavy made... you changed the plans and this changed the boat...

the interior is really nice but why did you build so many doors in solid hardwood??? and why this big engines and the hydraulics???

i did it and 90% of all home builder do it... we make thinks stronger then written in the plans and overbuild the boat... instead of increasing safety, we decrease it... ( in the worst case)

our draft is 1.1m. i thinks in the plans is written 0,9m...???

anyway... not much you can do now... luckily you did it on a wharram... this boats can life with it..

regards hans

ou boat in december 2012. fully loaded and ready to go.... borneo to singapore

 

[paul anderson]

great reading here, from what i gather these cats will take a bit more weight than is suggested in the plans ?

[Dave Vinnicombe]

We built 2 T38's together in the same yard, my boat Dragon and New Horizons. Dragon was built as light and as strong as I could by using lighter woods and ply. New Horizons wasnt as fussed as I was. So she was marginally heavier. We sailed both boats and I think New Horizons slightly heavier weight made for a better motion through the water. Dragon quickly 'gained weight' with her cruising gear, but even fully loaded never got closer than about 75mm to the chine.

So a little bit of extra weight is not a bad thing, just dont overdo it. You'll know you have if she sails like dog!!!

Cheers,

Dave

[wakataitea]

don't get it wrong... the wharrams made the plans right... the mistage is on our side (builder)

cheers hans

paul anderson said:

great reading here, from what i gather these cats will take a bit more weight than is suggested in the plans ?