As Travis says "dinosaur parts"

BillD

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Anyone want to hazard a "guess" if there would be any "speed increase" or "smoothness" in a typical 32-34 DE hull ditching the bronze stern tube and going with a shaft tube with a bit more "clean water" to the prop ?

Maybe a 1/2 knot or more???

Anyone ???????

Dinosaur Stern Post.jpg
 

petrel

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They didn't just do that on the West Coast, did they?
 

BillD

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old post by samhop

more numbers after changes looks good.
ok so it looks like the upgrade has worked out better than i had hoped for.
im not much with math so bear with me and any input would be great as i have a hard time rapping my brain around this.

light i get +200 rpm over and better than a knot WOT 2900 22kn+ should top out at 2600rpm

i get a + knot at cruse 2100 = +16kn used to be 15kn

full fuel 290g = 2300lb still get 200rpm over and a knot at cruse

full fuel 290g. = 2300lb + 3000lb of gear and 3 men i still get 2800rpm 100 over and cruse at 13 with over 5000lb fuel and gear on the boat. used to get 11 to 12 loaded with gear.


so from the hip it looks like +5% on speed +10% on rpm

what is the most surprising to me is the increase in rpm, the fact that i get more speed at a given rpm. the explanation i got on this from an engineer that works in jet turbines was that "the increased rpm and speed poss a strong argument that there has been an improvement in both hull and prop efficiency". apparently turbulence at intake is extremely important.

now this sounds right to me but i dont know for sure its a boat right.

As to fuel consumption im thinking the sweat spot should stay the same and raise my geustament to 4% fuel saving we will see once i get a couple of thousand gallons of #2 through it. next time i get dry might put 1in back in the wheel.


"looks like he gained about 1 knot @ cruise"

"the post by Travis" after samhop's shaft rehab.

That's good math right there

Why anyone would haul around dinosaur bronze parts is beyond me
 

greg

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Wow, didn't know I was driving a dinosaur. I've got that gear plus a glass rudder.

Anyone wanna venture a guess what the doctors bill would run on a chop job like that?
 

samhop

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Nooooooooooooooooooo....siree

I pulled this off the web.....Figure Maine builders maybe 5 years ago.

Any guess on the speed ?

Hi BillD
is this a virtual question about putting a keel on your blackfin :D or did you upgraded to a real boat?

with the weather we have been having i only got about 500gal through it so i cant tell ya on the fuel. i can say that the savings are not really being realized -- it's hard to back the throttle down.
 

MDI45

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Wow, didn't know I was driving a dinosaur. I've got that gear plus a glass rudder.

Anyone wanna venture a guess what the doctors bill would run on a chop job like that?
Greg,I am driving a big dinosaur also I guess...lets do a survey how many Dinosaurs are on this site
 

petrel

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I've got dinosaur running gear like that w/ the obsolete wet keel, but it is from 1980. The boat doesn't burn nearly enough fuel to justify conversion to fiberglass tube even if I did all the work myself. Course it's cheaper if you don't even have the boat to make these changes to, LOL.
 

BillD

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Hi BillD
is this a virtual question about putting a keel on your blackfin :D or did you upgraded to a real boat?

with the weather we have been having i only got about 500gal through it so i cant tell ya on the fuel. i can say that the savings are not really being realized -- it's hard to back the throttle down.

I still have the Blackfin, no keel going on her.
I continue to do my "homework" (most likely bore all of you :D) on getting every knot out of these 16K-20K hulls call DEs, lobster boat hulls, single keel hulls, whatever.
 

BillD

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Wow, didn't know I was driving a dinosaur. I've got that gear plus a glass rudder.

Anyone wanna venture a guess what the doctors bill would run on a chop job like that?

Hi BillD
is this a virtual question about putting a keel on your blackfin :D or did you upgraded to a real boat?

with the weather we have been having i only got about 500gal through it so i cant tell ya on the fuel. i can say that the savings are not really being realized -- it's hard to back the throttle down.

Greg,I am driving a big dinosaur also I guess...lets do a survey how many Dinosaurs are on this site

I've got dinosaur running gear like that w/ the obsolete wet keel, but it is from 1980. The boat doesn't burn nearly enough fuel to justify conversion to fiberglass tube even if I did all the work myself. Course it's cheaper if you don't even have the boat to make these changes to, LOL.

Jeeze, I inadvertently threw Travis under the bus on this one !!! :D:D:D:

I LIKE the idea of you guys starting a "poll" !!!!
 

Old Mud

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Badlatitude

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HA i have you all beat! Double vision was a single diesel with no keel! Worst of bolth worlds! :-?
 

WoundUpMarine

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MDI45

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I still have the "dinosaur" gear. i dont think it would be worth the change over unless i was repowering, and even then i dont now if i want to give up the extra "ballast" down low she rolls bad enough as it is. I would love to get rid of the rudder stuff box though!
iI would love to get rid of the rudder box also.....the one's Travis uses are real nice
 

WoundUpMarine

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MDI45

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im going to put a stainless rudder on next year, might see about putting one of those seals on, might have to have travis make a road trip down to boothbay to lend me a hand!
He posted a few pictures of a rudder box rebuild awhile back...Travis's Father installed one on my friends 34 Wayne Beal and it is a sweet set up
 
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