More V - C-series

[Johnston]

It seems to me that these are good hulls from everything I have researched - they have nice high sides, the look great and are obviously off-shore capable - but I would prefer them to have more dead rise as I feel that the shallow V will be uncomfortable in certain sea conditions.

Is this something one could modify?

I am looking at a C19

[fallguy1000]

Not really practical to change the d-r.

There are a couple of factors..

-bending of the plywood
-modifying scantlings for more offshore use

So, if you want more deadrise, you find a hull design with it and then modify that which can be modified; like sheer or internals, etc.

The compromise for more deadrise is a boat that rocks like crazy adrift or abeam; so deep deadrise is not always desirable for all boats.

[Johnston]

Is it not fair to say that around 20 degrees is considered more normal for this type of hill for running off shore?

What other plans should I be looking at if I want a smoother ride offshore into the sea?

[OneWayTraffic]

MG20. Barraman made a good one.

But if you really want smooth passage into choppy headseas and don't need to go fast, I'd look at a Panga. Deadrise is overstated imo, the designer wrote a lot about it. Look for some of his posts on the topic.

[TomW1]

You really cannot change the deadrise as it changes so many other things on the plans. Shapes of the bulkheads and stringers amount of wood needed for the bottom. For one the C19 is very seaworthy going out to the gulf stream off FL. The deadrise is not as important as how the whole boat is designed. Why do you think you need more than the 12 degrees deadrise? The 12 degrees is only at the stern it is much more at the bow and midship. The MG20 has more deadrise than the C19 but is a smaller boat due to its narrower beam. I love the C19 and have followed JimW and his build which was the first one built back in the late 1990's or early 2000's. He has caught marlin and Mahi off FL. His motor is a 115HP Yamaha and top speed is a little over 40.


Tom

[Johnston]

MG20. Barraman made a good one.

But if you really want smooth passage into choppy headseas and don't need to go fast, I'd look at a Panga. Deadrise is overstated imo, the designer wrote a lot about it. Look for some of his posts on the topic.

I had actually bought Panga plans - but to me it looks very flat towards where the boat would cut water on plane. I would be interested to hear from actual Panga owners about how the feel in chop/ head-seas.

I do also realise that deadrise is not the whole story but there must be a reason why boats designed to take on rougher seas (whilst maintaining speed) have deeper Vs?

[Jaysen]

Ahem.... let me get me stance proper....

TRADITIOOON!!!!

That's a huge oversimplification but much of the current understanding isn't understanding but observation of "traditional" semi displacement boat building. Don't get me wrong, you need a V to cut the wave, but once it's cut, a wide boat will STILL rise up and over. It might as well be flat, fast, and efficient. When you get into weather where a flat a$$ boat with a fine/steep entry becomes a problem, you are hating big deadrise too.

That's how I understand it. Hopefully Evan, the naval architect, will explain it (or my error) better.

Pangas are built for efficiency in materials and use more than comfort. Keep that in mind. Not saying they aren't comfortable. Just saying I'm taking a LOT of dramamine before I get on one.

[OneWayTraffic]

There was one built in Hawaii. Builder had it out in 25 knots plus more than once. No banging or slapping. The boat was explicity designed to go at moderate (not fast!) speeds in formed seas. According to the builder the chop hits the hull forwards, where it is definitely not a flat hull.

viewtopic.php?p=379297#p379297

It would be my choice if running through seas is a likely event.

[BarraMan]

The compromise for more deadrise is a boat that rocks like crazy adrift or abeam; so deep deadrise is not always desirable for all boats.

What is considered to be "deep deadrise"?

My boat has 18 degrees of DR at the transom, which I consider to be moderate V.

It definately DOES NOT "rock like crazy"!

I think deep V is >=20 degrees - perhaps closer to 22!

[bklake]

I'm going through a deadrise education the hard way right now. I got a new boat with a 15deg deadrise and it slams more than my old boat with a 22deg deadrise. I am learning how to control the slamming better. And, it is controllable.

In general, the new boat rocks on the water a lot less. Very true that a deep vee will rock. I never liked the rocking motion. When moored or tied up with other boats, my old boat rolled a lot more than others. The new boat slams a lot more so it is true that shallow vee slams more.

I have slammed my deep vee very hard, teeth breaking hard, before. A combination of doing everything wrong at the worst possible time. On the new boat. I have so far, soften some sure slams in the shallower vee by doing everything right at the right time. Conclusion: Vee is not a guarantee of a smoother ride.

I have seen and read reviews on shallow vee boats that are known for their smooth ride and stability. I think it has to do with how the bow cuts the waves and a few other factors. I don't care what hull you have, there is no boat that can go smoothly through chop at 35kts and not slam. Slamming is 99% controlled by the knucklehead at the helm. I was on the USS Roosevelt in a storm with waves breaking over the bow. It was slamming. Man has not yet made a boat that can defeat Mother Nature. You can dance a beautiful dance with her but you better not square off with her.

Don't get mired in the vee at the transom. Factor everything in. Most importantly, get a ride on a boat that you are interested in, in the conditions you need to evaluate. Some will surprise you. Both ways.