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Old    Darren Yearsley (ralph)      Join Date: Apr 2002       07-17-2013, 4:27 PM Reply   
So just had a PM discussion about the Malibu Power wedge where I suggested that the wedge would provide lift if in the launch position. I have reliably informed that in the real world it doesn't.

Why is that? What angle is the foil in when positioned in "start" mode?
Old    Art (rallyart)      Join Date: Nov 2006       07-17-2013, 4:55 PM Reply   
The Auto setting reduces the wedge angle when starting but I don't know that it puts it far enough forward that it generates lift. I think it just sets it to minimum load so it does not keep the stern dragged down when not necessary. Maybe it could go forward enough to create lift but I'm not familiar enough with the newest units. The level of the plane would have to be up at the front edge in relation to the hull.
Old    Mark (FunkyBunch)      Join Date: Jun 2011       07-17-2013, 5:45 PM Reply   
It would only need to hold the all the way down position. As the bow rises and stern sinks during launch the front of the wedge would have that angle your talking about. It does not make sense for them to position the wedge any other way for the auto set but maybe they did. The boat review that I remembered did not mention it calculating bow rise etc to adjust the wedge position.

The wake plates work on take off in a similar manor. At the level position the wake plate does not provide lift until the stern sinks. Since some boats have more stern heavy wetted surface the wake plates are always lifting the rear of the boat while the plate is level with the rear of the boat.

The summer boat show is this weekend here in Dallas I will take some pics of the different plates and go by WSA on the wedge.

Last edited by FunkyBunch; 07-17-2013 at 5:52 PM.
Old    Brett Yates (polarbill)      Join Date: Jun 2003       07-17-2013, 7:38 PM Reply   
How does prop thrust play into the equation? The reason I ask is it doesn't matter what angle the boat is at. The only thing that matters is the angle of the wedge plate as it compares to prop thrust.
Old    Art (rallyart)      Join Date: Nov 2006       07-17-2013, 11:28 PM Reply   
The angle of a hydrofoil plane is affected by the direction of water flow. When the stern sinks the water flow that the wedge meets is not the same as the direction of the boat. It is the same as the water flow along the hull which is where it gets it's water from Water is displaced to the sides when launching with the stern down. The water under the boat is just following the hull, at the centre of the hull. The foil of the Wedge acts the same, almost, as it does when the boat is running at or near plane. (I'm sure I could state that clearer if I was not tired but hopefully it makes enough sense)
The flow from the prop is slightly down but has probably straightened out by the time it is all the way back to the foil. Being slightly down would create more downforce on the foil but being more turbulent would make the foil less effective, so who knows.
Old    Seahawks #1 Fan Robert T (cwb4me)      Join Date: Apr 2010       07-18-2013, 3:27 AM Reply   
Since it's in the water behind the hull by several feet it is useless as a plane aiding device.The auto mode is creating less drag so the boat can get on plane faster than when it's fully deployed.Wake plates are attached to the rear of the hull at the transom.They act like a hull extension and adjust the attitude of the boat.
Old    Charlie Koch (cwkoch)      Join Date: Aug 2006       07-18-2013, 6:38 AM Reply   
The wedge at full down position is still creating downforce. Period. Just less of it than with the wedge partially up. It doesn't matter if the bow is pointed up, the wedge is still creating downforce IN RELATION to the hull....
Old    C.I.E. J-Rod (jarrod)      Join Date: May 2003       07-18-2013, 8:23 AM Reply   
Quote:
Originally Posted by cwkoch View Post
The wedge at full down position is still creating downforce. Period. Just less of it than with the wedge partially up. It doesn't matter if the bow is pointed up, the wedge is still creating downforce IN RELATION to the hull....
Correct.
Old    Chris (cjh1669)      Join Date: Apr 2005       07-18-2013, 8:27 AM Reply   
Quote:
Originally Posted by cwkoch View Post
The wedge at full down position is still creating downforce. Period. Just less of it than with the wedge partially up. It doesn't matter if the bow is pointed up, the wedge is still creating downforce IN RELATION to the hull....
Exactly, the wedge is a drag device not a planning device
Old    Art (rallyart)      Join Date: Nov 2006       07-18-2013, 11:24 AM Reply   
More awake now. The wedge is not actually a drag device. It is a hydrofoil device that uses water flow to create downforce. The greater the angle of attack down, the greater the downforce. If it was designed to have an 'up' angle of attack (and it never used to be) it could create lift on the stern. This would be a change from previous models and the lift at slow speeds while getting out of the hole would not be much anyway because it is small and would be as efficient a wing shape as might be necessary for that purpose.
My comments with regard to lift could only apply if the wedge were to swing far enough forward for it to have an 'up' angle of attack.
Old    Chris (cjh1669)      Join Date: Apr 2005       07-18-2013, 11:30 AM Reply   
Quote:
Originally Posted by rallyart View Post
More awake now. The wedge is not actually a drag device. It is a hydrofoil device that uses water flow to create downforce. The greater the angle of attack down, the greater the downforce. If it was designed to have an 'up' angle of attack (and it never used to be) it could create lift on the stern. This would be a change from previous models and the lift at slow speeds while getting out of the hole would not be much anyway because it is small and would be as efficient a wing shape as might be necessary for that purpose.
My comments with regard to lift could only apply if the wedge were to swing far enough forward for it to have an 'up' angle of attack.
So the short of what you're saying is, in it's current configuration, it is a drag device and not a lift device
Old    Mark (FunkyBunch)      Join Date: Jun 2011       07-18-2013, 12:26 PM Reply   
So did some research and what I found was that the power wedge will not go past about an 85 angle. This would create a drag at any time. The manual wedge will go to 90 but it floats or is set to other positions so it will also not help. Since I started this I can end it. It will not work to create lift as it is implemented. If they would allow it to go down to 90 and hold it that it would help to plane.
Old    Delta Force (wakebordr11)      Join Date: May 2001       07-18-2013, 12:48 PM Reply   
Quote:
Originally Posted by FunkyBunch View Post
So did some research and what I found was that the power wedge will not go past about an 85 angle. This would create a drag at any time. The manual wedge will go to 90 but it floats or is set to other positions so it will also not help. Since I started this I can end it. It will not work to create lift as it is implemented. If they would allow it to go down to 90 and hold it that it would help to plane.
Ralph and I are working with the Malibu designers now to sell them our idea
Old    Darren Yearsley (ralph)      Join Date: Apr 2002       07-18-2013, 1:25 PM Reply   
I'm not asking for much remuneration, just a 23 LSV in black and metal flake silver with LS3 please. With new "Malibu launch" (tm) technology of course.
Old    Mark (FunkyBunch)      Join Date: Jun 2011       07-18-2013, 1:38 PM Reply   
Well while your at it make sure they are building in the adjustment of when the "Malibu Launch" stops holding the launch position and moves into its normal position. Ex. at 85% of perfect pass speed etc..
Old    Art (rallyart)      Join Date: Nov 2006       07-18-2013, 2:31 PM Reply   
Quote:
Originally Posted by ralph View Post
I'm not asking for much remuneration, just a 23 LSV in black and metal flake silver with LS3 please. With new "Malibu launch" (tm) technology of course.
But then you would just be riding in a Malibu and not your current beautiful boat.
Old    Justin Harrelson (skiboarder)      Join Date: Oct 2006       07-18-2013, 2:53 PM Reply   
I run my MXZ 22 with about 3200# of total ballast and wedge all the way down. In the down position it is still generating a lot of downward force.

I don't know if a lifting force could be created with the current wedge system, but it would be a cool feature especially since I have been running more weight towards the rear this year. I'd buy it!
Old    C.I.E. J-Rod (jarrod)      Join Date: May 2003       07-18-2013, 3:17 PM Reply   
That idea is an old one. CIE Allen had the idea of making the wedge create lift for getting on plane years ago. I believe he and Adam McCall discussed.
Old    Darren Yearsley (ralph)      Join Date: Apr 2002       07-18-2013, 4:17 PM Reply   
Quote:
Originally Posted by jarrod View Post
That idea is an old one. CIE Allen had the idea of making the wedge create lift for getting on plane years ago. I believe he and Adam McCall discussed.
Well that doesn't add much to my reputation for legendary powers of innovative thought.

What about a aerofoil on the tower.... Ha ha, remember that monstrosity
Old    Gene Williams (gene3x)      Join Date: Apr 2005       09-24-2013, 10:29 AM Reply   
I would actually love to hear an argument as to why it wouldn't work from the manufacturer.
As I see it the wedge would have to be mounted so that it was out from the stern a little bit so that an angle greater than 85 degrees could be achieved.
Old    Delta Force (wakebordr11)      Join Date: May 2001       09-24-2013, 11:43 AM Reply   
Quote:
Originally Posted by gene3x View Post
I would actually love to hear an argument as to why it wouldn't work from the manufacturer.
As I see it the wedge would have to be mounted so that it was out from the stern a little bit so that an angle greater than 85 degrees could be achieved.
How do you know it is an angle of 85 degrees?

How much down-force does the wedge make? If you hit something with the wedge there have been instances where the transom rips off, then you want to put it on a standoff bracket? I'm not saying it won't work, I'm just questioning your engineering.
Old    Darren Yearsley (ralph)      Join Date: Apr 2002       09-24-2013, 11:51 AM Reply   
You don't necessarily need to change the travel on the arms, just shim the foil to the arms to create more angle relative to arm position
Old    Delta Force (wakebordr11)      Join Date: May 2001       09-24-2013, 12:02 PM Reply   
Quote:
Originally Posted by ralph View Post
You don't necessarily need to change the travel on the arms, just shim the foil to the arms to create more angle relative to arm position
But then when you run 3 clicks up, it won't be the same as 3 clicks up now... Throw everything out of whack.
Old    Darren Yearsley (ralph)      Join Date: Apr 2002       09-24-2013, 12:10 PM Reply   
Yes your right. You might need to ride 6 clicks up. Terrible, you might never get to grips with it. Ha ha.
Old    Delta Force (wakebordr11)      Join Date: May 2001       09-24-2013, 1:11 PM Reply   
Quote:
Originally Posted by ralph View Post
Yes your right. You might need to ride 6 clicks up. Terrible, you might never get to grips with it. Ha ha.
Not necessarily. You'll run the same foil angle in theory but its position in relation to the transom will be different, I am not convinced of your engineering
Old    Gene Williams (gene3x)      Join Date: Apr 2005       09-30-2013, 1:16 PM Reply   
What I was saying is that in order to set the wedge at an angle which it would push up instead of drag down the pivot point at the top of the swing arm would have to be away from the transom in order to achieve an upward angle.
With the way the wedge sits currently the swing arm would hit the transom and not allow the wedge to "swing up underneath the boat and therefore create an upward angle.

In saying that, a bracket mounted away from the transom most likely wouldn't be strong enough and if a portion of the transom were cut away in order to let the arm swing up underneath it would most likely change the wake significantly.

I kinda answered my own question. The 85 degrees came from Mark and his research as he stated above.

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