Deadrise ?

[Marcq]

Every once in a while a see the mention of deadrise in degrees, what is a deadrise and what kind of deadrise do I have on my boat ?

Marc..

[Capt. Bob]

Every once in a while a see the mention of deadrise in degrees, what is a deadrise and what kind of deadrise do I have on my boat ?

Marc..

Deadrise often occurs each year on the 31st of October. :o

Modern day deadrise occurs each week at approximately 4:30pm. This event, which takes place in businesses all across the United States, is associated with the coming of the weekend festivities and the bewitching event known as "Happy Hour"

Deadrise as it pertains to your boat is another topic altogether. There resides on this Forum a learned doctrine on the meaning of deadrise. While I haven't seen it in a while, it might be found in the resource section.

In short, I believe, deadrise is the angle formed by the hull, at the very end of the stern, measured at the hull's bottom (keel). The type of hull (Osprey, CCP, flatback ect.) determines it's deadrise. It is often found in the manufacturer's spec sheets which, for your craft, may be listed in the photo gallery section.

[Marcq]

Deadrise often occurs each year on the 31st of October. :o

Modern day deadrise occurs each week at approximately 4:30pm. This event, which takes place in businesses all across the United States, is associated with the coming of the weekend festivities and the bewitching event known as "Happy Hour"

Your a funny guy aren't you !  

Thanks for the other more believable explanation  

Marc..

[Capt. Bob]

Marcq,
A good explanation is in the Resource Section
http://classicaquasport.com/smf/index.php?topic=2915.0

I'd bet you'll find your boat's deadrise in the Gallery.

Good luck and Good Morning.

[Marcq]

I actually have the original brochure that came with my boat and there's no mention of deadrise on it, and can't find anything about it in the gallery ether

I'll keep looking
Thanks, Marc..

[Bahi]

While searching for a definition for the word "DEADRISE", I found the below detailed explanation, which I consider a perfect one. Hence, I just thought of sharing it with you. BTW, as per Aquasport site, the Osprey 170' has a deadrise of 12 degree....
http://classicaquasport.com/smf/index.php?topic=2915.0

[Capt. Bob]

Marcq,
If all else fals. you can get rather close by measuring the deadrise yourself.
Try drawing a line from a spot on the transom top (clear of the motor) and extend that line to the keel(hull bottom). Use a framing square to insure that the line is perpendicular to the transom top.
Use a protractor (or a speed square) and measure the angle formed by the line and the bottom. This will be 1/2 of the rise of course.

I did this when I first purchased my 84. and I believe I measured about 20 degrees (I believe the CCPs were either 19 or 20 degrees). Should be close enough for Govt. work.

[GoneFission]

As a general rule, semi-V Aquasports (Osprey, 170, 196, 222, and 196FF) all have a 12 degree deadrise hull.  

The deep-V models (CCP, XF, 222FF and 246FF, SR, all 24 and 25 footers) all have a 20 degree deadrise hull.  

Hope this helps!

[Marcq]

Thanks guys, now if somebody ask me what my deadrise is I'll know what to say, and show off how to mesure it :) ,  learn some every they

Should have done a search first, would have found Bahi post DOH  

But I have some bad news :(

Marc..

[Capt. Bob]

But I have some bad news :(

Marc..

And that would be.........

[Mad Dog]

Here is a link to a simple way to measure the deadrise.

http://dadmarine.com/angle2.htm

MD  

[Hardwater]

The link from dadmarine.com shows how to come up with another important hull spec - the transom angle...essential for fitting a transom bracket, for example, but different from the deadrise angle.

Deadrise for power boats with a planing hull is the difference, expressed in degree of angle, between the keel and the chine.  Go to Figure 1 to the right of the second picture down from the top in this link:

http://www.fish.state.pa.us/anglerboate ... tboard.pdf

There is a description below Figure 1 on how to calculate deadrise that's a lot better than my attempt above.  Most boat manufacturers will give the deadrise angle at the transom for different models...but if you want to really get into it, you can calculate the entry, or bow, deadrise (usually quite a bit steeper than the transom angle) and the mid-ship deadrise - the last 2 calcs are stuff that custom bunk trailer builders like to know.

Personally, I like Capt. Bob's first 2 definitions .

[Marcq]

Here is a link to a simple way to measure the deadrise.

http://dadmarine.com/angle2.htm

MD  

But that  only works if you have a predefine size Framing Square, I tried with two different ones and got a reading of 3 and 8

Thanks, Marc..

[Marcq]

The link from dadmarine.com shows how to come up with another important hull spec - the transom angle...essential for fitting a transom bracket, for example, but different from the deadrise angle.

Deadrise for power boats with a planing hull is the difference, expressed in degree of angle, between the keel and the chine.  Go to Figure 1 to the right of the second picture down from the top in this link:

http://www.fish.state.pa.us/anglerboate ... tboard.pdf

There is a description below Figure 1 on how to calculate deadrise that's a lot better than my attempt above.  Most boat manufacturers will give the deadrise angle at the transom for different models...but if you want to really get into it, you can calculate the entry, or bow, deadrise (usually quite a bit steeper than the transom angle) and the mid-ship deadrise - the last 2 calcs are stuff that custom bunk trailer builders like to know.

Personally, I like Capt. Bob's first 2 definitions .

Interesting read, looks like a simple way to calculate the dead rise if only I knew how to use a scientific calculator

Yup, Capt. Bob's method works pretty good

Marc..