Turning in vs turning out on V bottom??
#1
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Joined: May 2004
Posts: 861
Likes: 89
From: JUPITER, FL
I've got a Checkmate 2800SX outboard with twin Mercury 2.4L 200's. I'm running the motors on Gill brackets with 24" of setback at 18" centers. Running a straight edge off the bottom, the bullets of my noseconed lower units are about even with the bottom. The boat is very easy to trim up and the bow gets a bit flighty in rough water (the cabin is gutted for the time being-I'll eventually recover all the seats/V-birth pads with new vinyl and reinstall the wetbar). I've got the boat set up turning the props out right now but I'm in the process of swapping the lowers to try turning the props in. I'm hoping to pickup a few mph and some stern lift...any suggestions??
#2
Hello,
I believe we have spoken a bit about this before but if not.
Inward rotation will create more bow lift and less stern lift (from a physics standpoint).
Ultimately your seat of the pants observations will determine which rotation you prefer and the propellers can be modified to assist the boats attitude from there.
Brett
I believe we have spoken a bit about this before but if not.
Inward rotation will create more bow lift and less stern lift (from a physics standpoint).
Ultimately your seat of the pants observations will determine which rotation you prefer and the propellers can be modified to assist the boats attitude from there.
Brett
__________________
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
#3
Thread Starter
Registered

Joined: May 2004
Posts: 861
Likes: 89
From: JUPITER, FL
Hello,
I believe we have spoken a bit about this before but if not.
Inward rotation will create more bow lift and less stern lift (from a physics standpoint).
Ultimately your seat of the pants observations will determine which rotation you prefer and the propellers can be modified to assist the boats attitude from there.
Brett
I believe we have spoken a bit about this before but if not.
Inward rotation will create more bow lift and less stern lift (from a physics standpoint).
Ultimately your seat of the pants observations will determine which rotation you prefer and the propellers can be modified to assist the boats attitude from there.
Brett
#4
A 4 blade propeller such as our Blaster would be a great upgrade from the Chopper propellers. These props offer both bow and overall stern lift. They are very fast and are not as compromised by weight.
Let us know if you would be interested in testing these. So far they have been stellar on single and twin OB Checkmates.
Brett
Let us know if you would be interested in testing these. So far they have been stellar on single and twin OB Checkmates.
Brett
__________________
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
#6
Great question.
I usually tell people the only way to create bow lift is by pushing down on the ster. This is true unless you have a hull that induces its own bow lift to its aerodynamics.
The BBLADES Blaster is a 4 blade propeller with 14.75" of diameter. This in itself creates more stern lift than 3 blade 14.5" chopper. This is just the physics of the propellers. In addition, the Blasters have a aggressive rake angle and specific cupping in specific areas to add in leveraging the transom when positive trim is added. Therefore the props pick up the stern slightly while still being able to add tons of bow lift.
On my 20' padded V bottom these propellers provide more overall lift and trim than any other propeller I've tried or modified and I have tried a trunk load of them.
Brett
I usually tell people the only way to create bow lift is by pushing down on the ster. This is true unless you have a hull that induces its own bow lift to its aerodynamics.
The BBLADES Blaster is a 4 blade propeller with 14.75" of diameter. This in itself creates more stern lift than 3 blade 14.5" chopper. This is just the physics of the propellers. In addition, the Blasters have a aggressive rake angle and specific cupping in specific areas to add in leveraging the transom when positive trim is added. Therefore the props pick up the stern slightly while still being able to add tons of bow lift.
On my 20' padded V bottom these propellers provide more overall lift and trim than any other propeller I've tried or modified and I have tried a trunk load of them.
Brett
__________________
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
#7
Registered
Joined: Nov 2008
Posts: 23
Likes: 0
Hello,
I believe we have spoken a bit about this before but if not.
Inward rotation will create more bow lift and less stern lift (from a physics standpoint).
Ultimately your seat of the pants observations will determine which rotation you prefer and the propellers can be modified to assist the boats attitude from there.
Brett
I believe we have spoken a bit about this before but if not.
Inward rotation will create more bow lift and less stern lift (from a physics standpoint).
Ultimately your seat of the pants observations will determine which rotation you prefer and the propellers can be modified to assist the boats attitude from there.
Brett
#8
Registered

Joined: Dec 2009
Posts: 30
Likes: 0
From: Grafton, WI
Great question.
I usually tell people the only way to create bow lift is by pushing down on the ster. This is true unless you have a hull that induces its own bow lift to its aerodynamics.
The BBLADES Blaster is a 4 blade propeller with 14.75" of diameter. This in itself creates more stern lift than 3 blade 14.5" chopper. This is just the physics of the propellers. In addition, the Blasters have a aggressive rake angle and specific cupping in specific areas to add in leveraging the transom when positive trim is added. Therefore the props pick up the stern slightly while still being able to add tons of bow lift.
On my 20' padded V bottom these propellers provide more overall lift and trim than any other propeller I've tried or modified and I have tried a trunk load of them.
Brett
I usually tell people the only way to create bow lift is by pushing down on the ster. This is true unless you have a hull that induces its own bow lift to its aerodynamics.
The BBLADES Blaster is a 4 blade propeller with 14.75" of diameter. This in itself creates more stern lift than 3 blade 14.5" chopper. This is just the physics of the propellers. In addition, the Blasters have a aggressive rake angle and specific cupping in specific areas to add in leveraging the transom when positive trim is added. Therefore the props pick up the stern slightly while still being able to add tons of bow lift.
On my 20' padded V bottom these propellers provide more overall lift and trim than any other propeller I've tried or modified and I have tried a trunk load of them.
Brett
#10
With the larger diameters and multiple blades we have today, there are more options.
Brett
__________________
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]


