planning04models

So what happens if I just pull the nose up and leave it square?

This will sort of ride up over the water if you go fast enough - like water skis.

If not, it carries on pushing water along in front of it in a wave like the lego block does. The wave then sort of escapes round the nose on one side or the other sort of at random. This makes the boat change direction - violently.

This is easier to move than a square ended boat/raft, but is still like pushing the boat up hill.



Its also harder to steer than a pointy, but more about that later.



Sorry about the pics quality. They are photos of photos.

Testing the pulled up nose hull in a river.



Two pulled up hulls joined together with a mast and sails.



It was horrible to steer, but it did work.

If you dont mind it wandering off all over the place, this made a boat that would float in 2 inches of water - despite being 7 ft wide and 10 ft long (LWL was nearer 6 1/2ft)

This boat didnt sink.

It came close one day due to us sitting on one hull, which was filling with water, and pushing the boom away as we hadnt worked out how to tack.

The dog did all the technical thinking.

Er... not sure why this one has the crease line in the wrong place.

...and this one.

 

As he furiously tries them out and gets a set of pictures...between stopping the kids breaking stuff and answering the builders who are still pulling the roof about.....

He ended up eating the rest of the chocolate, dropping the gps, and now hes hacking out my paper boats - badly. Grrrr...



Still...back to the plot...

 

The sharper ended square nose....



I is still pushing a wave along like the raft did....



There isnt as much wake this time, as more is going under the boat. This was the case with the catamaran too - even under planing speeds, but more on that later.



Despite its improvement over the raft shape, it is still pushing a large bow wave, which costs energy.

I like this. You cant lift a boat out of the water and expect the trough to remain lol...



Dont rely on my telling you, build the boat and try it for yourself.

The shallower nosed punt/landing craft- as assembled by my little er...expert...



Difficult to get a pic, but there is very little bow wave with this boat. Most of the sugar is going under it.



Thats not to say its not still pushing a wave, only that its much smaller....



I think I need to have a word with my builder. Looks like it sank.

 

While we have these two boats on the sugar, theres another really important thing we need to look at.

Waves.

This is the flatter boat hitting a pile of sugar....



It doesnt ride up the pile as its angle is too shallow.

So it chops off the top and it ends up inside the boat.

However.....

The blunter one has a better angle for this and climbs the pile...



Its climbing was determined enough it actually bent the boat in the middle.

So.....

For flat water, you need a very shallow rise at the front, and for waves, you need a bunter end.

This is very important. In fact probably the most important bit so far.

For flat water, you need a shallow rise at the front and for climbing waves, you need a blunter shape.

So....

If the boat is curved from back to front and pointy in both directions, this should be the best yet.

Have a go at making another boat lol

This one is the same as a previous one, only this one has a different cut to the two ends. This different angle is enough to tip the sides out and rake the nose and curve the bottom. The curve to the bottom is called rocker.


Obviously, build quality...er...I was helped. lol



This one is pushing some sugar into a wake, and some is passing underneath.



I am trying to ignore the wobbly bottom and the horrendous leaks...



Still, even in this er..condition, its still proving the point.

Here its hitting the wave adn climbing over it like the blunter punt did.



The boat is bending rather than cut through the sugar.

Here its pushed its nose clear...



It rode over some sugar, pushed some into a wake and then pushed the top of the wave sideways out of its way...

Both the rounded bottom and the angled sides have done their work.



Have a go with the different hulls and look at how they perform.