Hull Recommendation

[Smelly]

Hi Team!

I want your valued opinions on the following:

New or used hull brand recommendation for following specs:

Location Mostly Used: # Port Phillip Bay Melbourne
Outboard Used: 40HP VWHTOL (2-stroke tiller) Yamaha
Material: #Aluminium
Vee: # Very Deep Vee
Steer: # # # Rear steer only (no center console or forward controls)

What is the maximum length hull recommended for 40HP?


Thanks in advance!

[Leo_N.]

Smelly,
With the deadrise angle, you need to be aware that the steeper the angle you have, the lower the planning area that you have, and more power you need to get up on (and stay on) the plane. A good example of this is the Nobel Super V boats. They have a really sharp angle and reportedly handle the chop extremely well, but need to be powered up a lot to keep the performance high. If underpowered they drop off the plane readily.

I have a mate up here in Townsville who recently bought a 4.5 m plate boat (I think an Allycraft tank) and has a 40 hp Yam on it. He is pretty wrapped in its performance. I thought that it would be under-horsepowered but the 40 gets it along fine with three people and gear. That would be the largest boat that I would put a 40 on though. It is only 3 mm plate though I am pretty sure. The extra weight of plate gives a much better ride than pressed aluminium, and weight is probably as important as v-angle in determining performance in chop.

[Smelly]

Many thanks Leo.

Is the 4.5 Tank deep vee?

Do you ride a plate boat?

Would you mid passing your mate's email address on to me?

cahird@bigpond.net.au

THis boat sounds very interesting and seems like the one I am after..

Leo, what are the main advantages of palte over pressed Aluminium?

Smelly

[Leo_N.]

I found some pics here:
http://www.offshoremarine.com.au/boat.asp?bid=499

and specs here:
http://www.allycraft.com.au/Showroom.aspx?ProdID=OB526

As you can see from the pics it has quite a large v in the bow, which flattens out quite a bit toward the stern. I don't have specs on the deadrise though.

The main advantages of the plate boat are extra weight which helps them punch through chop (rather than slapping as much) and generally stronger construction. If you look at the pics, you will see that there are a lot of ribs in this boat for strength. The welds are also very good.

The downside of plate is that the shape has to be quite simple. There is a trend these days in aluminium boats to press a flared bow into them (Quintrex and Stacer do this a lot). This gives great ride characteristics, but to press this type of shape into them the aluminium used has to be thin. Therefore they do not have the structural strength of a plate boat. These type of boats often need weld jobs on the hull after a reasonable amount of use in choppy conditions.

Having said that, I don't personally use a plate boat. I am waiting on my new Polycraft 5.3m centre console. No problems with corrosion or cracked hulls for me. The reason that I didn't advise the Poly for you is that you mentioned that you wanted aluminium construction.

I will pass on your email to my mate, but he is away atm and if he does get back to you it won't be for a month.

Cheers,
Leo

[Smelly]

Many thanks Leo.

So much choice out there..

I thought a deep vee in the stern would be what is required to achieve good Deep - Vee characteristics - not just in the bow - is this the case when looking to buy a deep-vee hull?

Smelly

[Leo_N.]

It is a bit of a trade-off really. Lower deadrise angle at the back does decrease the ability of the boat to move through the waves/chop as effectively, but it gives a larger planing surface area, which is very important for getting up onto the plane and staying there, especially when limited in your hp. Having a sharp v at the front is all important as that is where you first hit the chop. But if you had the same angle throughout you would really struggle to get on the plane.