# What do all the measurements on a boat mean



## MooreMiller (Sep 10, 2016)

Deadrise is the measure of the "sharpness" of the V of the hull. Deadrise is measured in degrees and the larger the number, the softer the boat will ride. 

A 1,000 lb boat with 6 degrees of deadrise at the transom will beat you up in a heavy chop. Where a 1,000 lb boat with 15 degrees of deadrise at the transom will have a much softer ride. 

"Adding" deadrise to a boat will usually increase the wetted surface of the hull, which causes more drag on the hull and will make the boat slower. Hulls with more deadrise usually need a bigger outboard as a result. 
Hulls with more deadrise usually draft more than hulls with less. 

There are lots of exceptions and this may be an over simplification but that is the concept.


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## Austin98 (Jan 19, 2017)

MooreMiller said:


> Deadrise is the measure of the "sharpness" of the V of the hull. Deadrise is measured in degrees and the larger the number, the softer the boat will ride.
> 
> A 1,000 lb boat with 6 degrees of deadrise at the transom will beat you up in a heavy chop. Where a 1,000 lb boat with 15 degrees of deadrise at the transom will have a much softer ride.
> 
> ...


Thank you, that really helped me understand the concept.


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## paint it black (Nov 3, 2007)

LOA: Length Overall. Meaning the overall length of the hull at it's longest points. 
Beam: the width of the boat at it's widest point. Some manufacturers will state the beam at the widest point, and beam at the waterline. 

Transom Height means how many inches from the top edge where the motor will be mounted, to the low edge. This matters as some motors are short shaft and others are long shaft. Usually, short shaft means 15", and long shaft means 20".


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## Steve_Mevers (Feb 8, 2013)

MooreMiller said:


> Deadrise is the measure of the "sharpness" of the V of the hull. Deadrise is measured in degrees and the larger the number, the softer the boat will ride.
> 
> A 1,000 lb boat with 6 degrees of deadrise at the transom will beat you up in a heavy chop. Where a 1,000 lb boat with 15 degrees of deadrise at the transom will have a much softer ride.
> 
> ...


Spot on description of deadrise!!


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## Capnredfish (Feb 1, 2012)

Skinny and tippy may not have numbers but around these parts are very important and often exaggerated.


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## THX1138 (Dec 20, 2016)

Cool, good info here for us newbies ;-)

Lou


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## paint it black (Nov 3, 2007)

Oh yeah, freeboard is the height measurement of the hull sides.


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## commtrd (Aug 1, 2015)

Tumble home?


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## firecat1981 (Nov 27, 2007)

Tumble home is when the rear portion of the sides right before the transom actually curve in, instead of out. It's a design element and serves no practical function, so you don't see it often.


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## CurtisWright (May 9, 2012)

In can


firecat1981 said:


> Tumble home is when the rear portion of the sides right before the transom actually curve in, instead of out. It's a design element and serves no practical function, so you don't see it often.


in canoes, tumbleholm gives you more room to paddle without having to lean too far over.


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## East Cape (Sep 3, 2015)

firecat1981 said:


> Tumble home is when the rear portion of the sides right before the transom actually curve in, instead of out. It's a design element and serves no practical function, so you don't see it often.


My .02
Tumble home is the opposite of flare. it's done just above/at the waterline and gives secondary stability...
Hope this helps?
Kevin


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## jonrconner (May 20, 2015)

paint it black said:


> Oh yeah, freeboard is the height measurement of the hull sides.


It's actually the measurement from the waterline up to the gunwhale, the more you load the boat, the less freeboard you have.
JC


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## WhiteDog70810 (May 6, 2008)

What is a hollow forefoot? I have tried to find a definition in the past and failed.

Nate


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## Zika (Aug 6, 2015)

firecat1981 said:


> Tumble home is when the rear portion of the sides right before the transom actually curve in, instead of out. It's a design element and serves no practical function, so you don't see it often.


Tell that to the Outer Banks builders who designed it and the true Carolina flare to handle big seas and shallow draft scenarios like Oregon Inlet and they'll laugh you right out of Wanchese.


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## firecat1981 (Nov 27, 2007)

Tell what? That tumble home serves no real benefit? Please tell me what it does then?


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## DuckNut (Apr 3, 2009)

Zika said:


> Tell that to the Outer Banks builders who designed it and the true Carolina flare to handle big seas and shallow draft scenarios like Oregon Inlet and they'll laugh you right out of Wanchese.


You're thinking of flare.


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## DuckNut (Apr 3, 2009)

commtrd said:


> Tumble home?


Is what anytide does on a saturday night.


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## Zika (Aug 6, 2015)

East Cape said:


> My .02
> Tumble home is the opposite of flare. it's done just above/at the waterline and gives secondary stability...
> Hope this helps?
> Kevin


Reduces weight above the waterline on narrower beam hulls. Was also used to hinder boarders and deflect cannon balls in warships.


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## firecat1981 (Nov 27, 2007)

Tumble home does not reduce any significant weight, nor is it used on many narrow hulls outside of gheenoe type designs, which isn't technically a tumble home anyway. As mention previously it is design element used mainly on modern displacement or semi-displacement cruisers. Boarders and cannon balls....really man?


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## Zika (Aug 6, 2015)

Sorry firecat. Didn't realize I was parlaying with a naval architect.

The OP asked a general question about boat design measurements and terminology, not specifically to microskiffs. Does tumblehome play a significant role in craft weighing less than a thousand pounds? Probably not much. But in boats much larger like those designed and built by craftsmen on the Outer Banks for decades, it does come into play for stability and recognized style. The warfare reference was added for historical context, which I thought OP might appreciate since he wanted to learn the meanings of various definitions.


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## firecat1981 (Nov 27, 2007)

No problem, and I prefer debating with a Seafaring Originator. I don't do parlays.


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## EdK13 (Oct 3, 2013)

DuckNut said:


> Is what anytide does on a saturday night.


Allegedly.


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## WhiteDog70810 (May 6, 2008)

Tumblehome definitely helps stability in a boat, especially the soft chined vee bottoms on which TH is commonly found, because it keeps the human cargo's big, moving butts confined inside the base of support where they belong. You can't walk a gunnel that isn't there. 

Remember that those Outer Banks boats ain't anchored on the flats with popping corks out. They are trolling for big fish. If I was gafting or unhook big fish, that tumblehome in the rear would definitely make reaching the fish easier for the same reason it makes a canoe easier to paddle. I suspect this is why they kept the feature. Old watermen aren't prone to extravagant stylistic elements that don't serve a function.

Any curve to the side of a hull in any dimension will increase longitudinal stiffness. FG allows us to dramatically stiffen hulls without twisting boards, but every little bit can help.

...and, yes, in the bad ol' days, tumblehome would keep the weight of the cannons closer to centerline than a flared side would have, thus keeping the CG of the ship inside its base of support, thereby improving secondary stability and allowing a given ship to carry more guns... ...and if you don't think that is cool, take long walk off a short plank.

Nate

PS, Hey FC, luv ya bro!


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## East Cape (Sep 3, 2015)

Let's not get into upper chine or style lines then...lol
Or strakes, inverted bottoms etc

I'll sit back and just read on this thread


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## Zika (Aug 6, 2015)

Photos are worth a thousand words...

Top two, tumblehome aft on a semi-custom Bayshore flats boat. The stern/outboard shot is also a good example of deadrise. This one is 11 degrees.
Bottom two, true Carolina flare on the same model. It poled in nine inches, by the way.

And yes WhiteDog, I've fished on several different builds of OBX sport fishers and know the difference between a popping cork, an 80 Wide and Omie Tillet. 
View attachment 5937
View attachment 5938
View attachment 5939
View attachment 5940


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## DuckNut (Apr 3, 2009)

Is that your boat?

Rosco is building a boat based on the same design. THis one is a production model.


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## tailwalk (Nov 20, 2016)

Thanks for starting this thread. Some of the aspects of design are totally foreign to neophytes like me. For example:


East Cape said:


> Let's not get into upper chine or style lines then...lol
> Or strakes, inverted bottoms etc
> 
> I'll sit back and just read on this thread


Strakes and Chine are two things I have little understanding of. Anyone care to break it down for the uneducated?


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## WhiteDog70810 (May 6, 2008)

Zika said:


> And yes WhiteDog, I've fished on several different builds of OBX sport fishers and know the difference between a popping cork, an 80 Wide and Omie Tillet.


I was yanking FC's chain, now I have to look up "80 Wide" and "Omie Tillet".

Nate


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## MooreMiller (Sep 10, 2016)

View attachment 5949


tailwalk said:


> Thanks for starting this thread. Some of the aspects of design are totally foreign to neophytes like me. For example:
> 
> 
> Strakes and Chine are two things I have little understanding of. Anyone care to break it down for the uneducated?



Strakes are those two long, thin things on the bottom of a hull in the pic. 

The ones in the pic most likely go all the way back to the transom and are designed to help lift the hull out of the water to lower the wetted surface and make the boat go more faster. Look what a bass boat looks like doing 70 mph. Lifting strakes. 

There are also long, thin strakes that are under the hull that serve to make the boat pole straight. Like fins on a dart. 

The chine is where the hull sides meet the hull bottom. The most common in power boat hulls are reverse or inverted chines. 

Reverse chines help throw spray down to the water and away from the cockpit of the boat. The boat in the pic has reverse chines.

Reverse chines can also give the hull a little bit of "lift", like a lifting strake. Right????

I'm no rocket surgeon, but I believe most of the answer is there.


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## CodyW (Jan 26, 2016)

DuckNut said:


> Is that your boat?
> 
> Rosco is building a boat based on the same design. THis one is a production model.


Did he ever finish that boat? The last video he posted was about a year ago and was close to finish.


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## DuckNut (Apr 3, 2009)

CodyW said:


> Did he ever finish that boat? The last video he posted was about a year ago and was close to finish.


I don't know. I did not know him personally so I can't answer that. Maybe Whitedog can - I think he might have more info.


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## Zika (Aug 6, 2015)

DuckNut said:


> Is that your boat?
> 
> Rosco is building a boat based on the same design. THis one is a production model.


Yes, owned this one for 13 years until recently. Bayshore Boats were semi-custom production flats boats built in Wrightsville Beach, NC. They also built a bay boat with similar lines. Only 56 were produced and the company eventually shut down. The molds were sold to and subsequently modified by Chaos Boats.


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## WhiteDog70810 (May 6, 2008)

DuckNut said:


> I don't know. I did not know him personally so I can't answer that. Maybe Whitedog can - I think he might have more info.


I've heard hearsay that he is side tracked with other projects. He'll be back one day. 

The work he has left to do is all the stuff that involves measuring 2-3 times, then very carefully cutting a hole in a surface he flawlessly prepped. I was took forever just to drill the hole for the drain.

Nate


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