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Anyone noticed more amps draw if we set the prop too deep in water, or just me?
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The deeper the prop runs in the water, the more loading on the prop and more amps.ReddyWatts fleet photo
M1 Supercat - Neu 1527 1Y, 8s / Mean Machine- Feigao 580, 8s, 120 HV esc
Mean Machine - Feigao 540 14XL, 8s, 100 amp HV esc, X537/3 -
Yep, you have to find that happy medium. Sometimes dropping the prop makes the hull faster but it also will cause the motor and cells to run hotter. I usuallyt start with a high strut and work my way down until it runs to hot and them back off a bit.Team Liquid DashComment
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The more you drop the strut the weter the ride pads are. This will stop blow over and slow you down and make the boat harder to push foward. If you watch the boat run and look at the ride pads as it goes in front of you, you do not want to see any water beeing pushed foward. You allso look for about one inch to 3/4" of water on the rear of the ride pad. Any more than that and you are too wet.
I look for 3.5 to 6.5 degrees of lift depending on the applacation.Comment
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Very good info. Is it possible please to explain the "3.5 to 6.5 degrees of lift" with a sketch or else? Thanks.Twin Cat 135, Sprintcat40 (single-twin), DF 35", Maritimo, Mean Machine, SV 27
http://www.rcfastboats.com/Comment
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OK this is how I do it I take a board big enough to place the boat on and level it all directions. This board is called a set up board. It has cut outs for the rudder and the turn fin and set up so the sponson hangs off the side of the board. Then I take a Protractor and place it on the rear 3 inches of the ride pad. Then I can read the degrees of the sponson attack. This is called inclination. If you turn the protractor 90 degrees then you are measuring the dihedral. The dihedral also will control your speed the flatter the faster. But the more angle the faster in the turns to a point, if you put too much dihedral in the sponson speed will be lost. 1.5 degrees is my max. I will take a picture at work and post it.Comment
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Randy, I searched an explanation for dihedral and now I am totally confused. I believe it refers to the angle between the sponsons or wings. How do you adjust this angle on fixed sponsons? Or does the strut angle and depth make the difference.
DouggieComment
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It is adust in the building of the boat and is a fixed angel on both sides of the sponsons of the bottom of the ride pads. If you were to look at the boat from the rear, the angle that the sponson rises is the dihedral.
Sorry I got carried away, As you know I am all about design of boats, it is one of my passions.
More pictures later.Comment
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I cannot understand it but don't worry. I guess this is used in hydros. For the word dihedral i can translate from greek as:
di=means two (dyo in greek)
hedral= means a seat (like exhaust valve seat) (hedra in greek)
Thanks for your rely.Twin Cat 135, Sprintcat40 (single-twin), DF 35", Maritimo, Mean Machine, SV 27
http://www.rcfastboats.com/Comment
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Randy, thanks for the answer and I trust all is well after your surgery. Take care and thanks for your major contributions to Fe boating.
DouggieComment
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You are welcome It means a lot to me.
I have been out from surgery about 6 weeks. It was a tough one, I am 95% recovered. I have some Blood vessel that were damaged and are regrowing them selfs this takes a while. Strange my dentist friend expalined to me better than the Surgen.Comment
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Dihedral. It's the angle of the ride pad running surface from inside edge to outside edge of the ridepad in relation to the water surface.
Inclination, angle of attack, AOA. It's the angle of the ridepad looking from the side of the sponson as it relates to the water surface.Comment
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Randy I took your picture and put a few lines on it to show the dihedral. I hope you do not mind.
The dihedral is the angle between the two red lines.
David explains it very well.
Several boats in various stages of destructionComment
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Good one Paddy! Between Dave N., you and my self we make a whole thought that makes sence!
Thanks
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