bevel chine vs square chine

[Thomas Williamson]

Would anyone hear like to share some advice on the pros and cons of a beveled chine vs a square chine on a small outboard powerboat? Any opinions would be most appreciated.

Thanks,
Thomas

[JimConlin]

I assume that you're asking whether to bevel the top edge of an internal chine.
If it eliminates a pocket where water and crud can collect, it's worth doing.

[Thomas Williamson]

Thanks for the reply Jim. However, my question was more general regarding the actual shape of the transom and aft part of the hull. I should have been more clear about this.

Thomas

[Kermit]

Oh. You mean the angle of the transom at the chine?

[whb]

Thomas

Are you actually talking about a small rounding off of the Chine say 3/4" radius or are you talking about a round bottom as on say the sides of some canoes (really no chine).

My understanding is that on a displacement boat a round bottom is faster and stronger. On a planing boat the Chine makes planing way easier and more efficient.

I think?

Howard

[Tom Lathrop]

Thomas, I think you get the point that to get a good answer, you need a better question. It's not possible to know what you need from your question. Try to be more specific.

I suspect that you are asking about the shape of the bottom near the chine in cross section, but it's not clear.

[ 09-04-2003, 08:17 PM: Message edited by: Tom Lathrop ]

[Big Red]

Thom, if your refering to rounding off the chine. Then from what I understand it will be an improvement. The sharper the angle the more drag this surface will create.

That is the water flow will have to change direction at the corner, creating eddy currents, which will slow you down. How much effect it will have is uncertain. Is there an engineering type out there with a slide rule handy? :D

Another advantage I can think of is its easier to glass over a rounded surface than an angled one.

Hope I am on the right track. Good Luck.

[rkrough]

I'm Assuming this is what you are thinking of http://www.duckworksmagazine.com/store/plans/jw/trover/Trover1.gif

My current project is an 18' displacement speed camp cruiser with outboard power. I'm going with a " beveled" chine to reduce the shoulder wave usually associated with the hollow entry of a vee type hull and to have a finer exit at the transom. The main objections to beveled chines that have been pointed out to me so far are the increased labor and materials especially with stitch and glue. Depending on the curve of the buttocks the boat might have less initial stability(feels tippy) . If you plan to sleep on the boat, any wave action will tend to slap under the chines.

[bassman]

Hi All,

I have been away from my computer for a few days attending the Simmons Sea Skiff show in North Carolina. It was great although we did get a lot of rain.

As far as the question goes, I think that "rkrough" got the idea of my not so clear question. The chine he shows in the diagram is along the lines of what I was asking about but the beveled portion would only be about 4-6 inches on a 48 inch transom on a planing hull with a 4.5 ft beam and an overall length of around 11 ft. The plans call for the beveled chines so that is how I am going to build it. However, I was hoping to get a little insight on the benefits of this design vs a more squared off chine.

Thanks for all the replies so far!