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Friday
Nov052010

Where was the water line?

If you have been following this blog for a while you will be aware that there was some concern that there may not be enough buoyancy in the stern for two reasons.  One is that the hulls were a bit narrower in that area than they were supposed to be.  The other being that we have decked in the aft section and added handrails and a heavy duty steering ram, with the resultant increase in weight.  So, we compensated for this by adding additional buoyance in the aft section.

We added a little more than we needed to based on the premise that if we put a bit to much in the aft end it would be easy to 'level' it up by the addition of a part 'torpedo' in the bow section.

If you have a look at the photos below you will see that the front of the hulls although above the marks is sitting a bit lower than the aft end. 

 

This is exactly what we were hoping for.   The water tanks were full as was the fuel tank.  The next step is that we will load all the cruising gear on board including drogues and parachute anchor and food etc...in other words what I expect will be on it 90% of the time.  At that stage we can check all the trim and if she is still slightly 'nose' down we can easily correct it.  But, by the time I load the spares and tools into the aft section that may not be necessary.

So...in summary...I am delighted with how it sits in the water.  If it had been down in the stern it would have been a real problem to correct.   We will take her for her first sail later today.

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Reader Comments (23)

well done
really beautiful
congratulations
fair weather

November 5, 2010 | Unregistered Commentermarc

Congratulations on the launch :) Here's wishing you fair winds...

Any chance of getting some finish photos from below decks?

November 5, 2010 | Unregistered CommenterBrian

Congratulations Warren she looks absolutely gorgeous, that aft facing sofa just oozes class, well actually the whole damn boat oozes class!
I'm facing an uphill battle to get 'Gleda' on the water for my target of May 2012 but seeing 'Natural High' afloat has given me an extra boost. Thanks for sharing the build with us and please keep blogging, I'll need some Tiki 38 adventures to keep me going!
Cheers

November 5, 2010 | Unregistered CommenterNeil

Thanks Marc...I really appreciate your good wishes.

November 6, 2010 | Registered CommenterWarren Matthews

Hi Brian...thanks for your good wishes. And yes, I intend posting a lot more photos of the interior below decks and other areas. I will also do more detailed reports on the details of the electric motors...the good and the bad points about them and explaining the mistakes made and how they can be avoided.

November 6, 2010 | Registered CommenterWarren Matthews

Thanks for that Neil. I really admire what you are doing and the perseverence that you are showing in your build, and of course the efforts that other home builders of Wharram cats are having to make. I have to confess that I would not have the patience to do that.

It is a much bigger undertaking than most people realise. I have not totalled up the manhours involved in my build. I stopped counting at around 10,000. I will total them up and let you know. Of course in some areas I went 'over the top' and if I was building it myself I would not have done many of the things that I have done.

I am pleased that my build has helped as an inspiration to you, and it is my intention to continue to report as I do the 'shake down' of the boat. I will be preparing it for the voyage to Fiji over the next few months and testing it in storm conditions and finding out how it handles them.

November 6, 2010 | Registered CommenterWarren Matthews

Congratulations, Warren!!!
Well done! She looks great.
Happy testing and sailing. Whish you fair wind.
Cheers,
Peter

November 7, 2010 | Unregistered Commenterpeter mirow

I can't help thinking of Cleopatra's barge when I look at the aft facing sofa together with that weather awning. I look forward to seeing her under full sail and cutting a wake. Nice build! Congratulations!

November 7, 2010 | Unregistered CommenterLaughingcruiser

Congratulations Warren she looks magnificent, the hard work of you and your team have paid off in spades mate. Good to see she handles well under power and sail too. I wish you many happy and safe sea miles in her.

Hears to a pretty little ship Cheers

November 7, 2010 | Unregistered CommenterChris Harrell

so now the boat sits bow down

November 9, 2010 | Unregistered Commentergerard

Thanks Guy's for your good wishes. Actually the aft facing sofa will make more sense when I post additional photos of how it all ties together. Hard to see with that photo.

Gerard...it is not that the bow is sitting low but rather the stern is a little higher which is exactly what I wanted. Over the next few weeks I will be loading her up with food and all the remaining cruising gear and tools. The water tanks are full as is the diesel tank, but I still have to add the chain for the back up stern anchor and stow a few other things aft..

It would like to put a small 'torpedo' shape under the waterline on the bow, after I have everything on board. This would improve downwind performance and it is really easy to do. With this I can ensure that the trim is perfect in the cruising form that I will be using it in. I will be posting detailed photos of the trim later. I am so pleased that I added the additional buoyancy aft otherwise I would have had a real trim problem.

November 13, 2010 | Registered CommenterWarren Matthews

something is wrong with boat's trim... seems your mistake warren
anyway happy sailing

November 17, 2010 | Unregistered Commentersubsea

Hi Subsea,

Not sure how you figure that I have a trim problem? We have not made a mistake. We put additional buoyancy aft to offset the additional weight in that area. It worked out perfectly. We ensured that there was a bit extra to allow for anything that we may have overlooked. The reason for that is because adding the aft buoyancy was a major operation and to add more later would have been a nightmare.

On the other hand if we found that we over compenstated in the aft end it would be a very simple matter to add a little more in the bow to balance it out. That may or may not be necessary.

I will not make the decision about that until I have got the boat fully kitted out with all the spares, cruising supplies, beer, food, fridges, freezer full etc, etc. This will not happen until I have used it for a while. Probably in January.

As you probably know, these boats are very sensitive to trim. It was launched with full water tanks and fuel tank. I still have to stow the parachute anchor, the drogue and other gear. Maybe another 400kgs. I am stowing gear where is is convenient to access in all conditions and where it can be kept tidy. In other words a place for everything. I could easily rearrange a couple of things now and have perfect trim but everything may not be where I want it for convenience.

So, no mistake...it worked out exactly as I had hoped. When the boat is in full cruising mode we will do an accurate assessment and may or may not have to fit a small appendage to the bow. As I mentioned that is no big deal and I beleive would enhance the overall performance of the boat...so, in a way I am hoping that it is necessary.

One thing for sure is that if we had not added the additional buoyance aft we would have had a major problem for the reasons I have outlined in earlier blogs.

November 17, 2010 | Registered CommenterWarren Matthews

so in your case trim is wrong but it is exactly what you wanted
with creed's boat it is a 'mistake', no matter where the tanks and other variables are
double standards?

in no load condition boat should sit bowdown but opposite is widely acceptable

November 23, 2010 | Unregistered Commentergerard

Hi Gerard,

I think that you are missing the point. There was a mistake in my original hulls as built by Raoul and which was also on Creeds boat.

For the sake of clarity here are the facts again.

1. The forward 75% of the hulls was wider than the original Wharram spec.
2. The aft 25% of the hulls were narrower than the original Wharram spec. That can be seen clearly from the photos on the blog.
3. The aft 25% if the hulls should have been faired in to match the rest of the hulls...but they were not. This is clearly a mistake.
4. Creeds boat sat on the water stern down because of this...and there was nothing stored in the aft lazerettes. If that area was used for storage as designed it would have been a disaster.
5. If I add about 100kgs of weight in the aft end 'Natural-High' sits perfectly level. I have not finished loading all the tools and cruising spares into the aft lazerettes so that will have an impact. However, most of the gear is already loaded including the spare anchor.
6. I have also not finished loading everything in the forward section either. For example I still have about 50kgs of sea anchor, drogue and rode to be fitted. Everything else is there though.
7. I also have to complete loading the boat with enough stores for two people for 30 days.

Only after I have completed all of the above will I make the final assessment of the trim. Quite frankly I am hoping that it will be slightly down in the bow because I feel that a small appendage in the bow section will improve overall performance in large following seas. But, I don't know if this will be neccesary at this stage. There is no point in making the final decision on trim until the boat is fully fitted out in ocean going cruising mode.

I know for sure that if I had not added the additional buoyancy aft I would have had a disaster on my hands. As it is I am extremely happy with the way it is sitting. So, sorry Raoul (Gerard),..no mistake on our part, and no double standard either.

November 24, 2010 | Registered CommenterWarren Matthews

to answer the question one should look at original lcb of wharram's design and lcb of modified hull
if they match there is no any mistake

mistake was adding so much volume aft on warren's boat and poor result is obvious now

November 24, 2010 | Unregistered Commentergerard

Oh come on Gerard/Raoul. Read my posts and face the facts. Where is no poor result. I will end up with a perfectly trimmed vessel in full cruising mode. I will post plenty of photo's and videos at that time for all to see. Unlike Creeds boat 'Natural-High' is a strong boat and a safe one capable of sailing any of the world's ocean's. In contrast Creeds could not even handle what we consider in New Zealand to be a gentle breeze. I truly shudder when I think what would have heppened if I had not removed the hulls from the yard and had them fixed in NZ.

November 24, 2010 | Registered CommenterWarren Matthews

warren seems you believe that everyone who disagrees with you is raoul
kind of madness?

November 24, 2010 | Unregistered Commentergerard

Gerard, the reason why I suggest you are Raoul is that your IP address is in exactly the same location in Pattaya as Raouls. Maybe its a coincidence!! Perhaps you have just borrowed his computer?

November 24, 2010 | Registered CommenterWarren Matthews

it is your obsession warren
understand without stories on raoul your blog is not interesting to read

November 24, 2010 | Unregistered Commentergerard

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