More Prop Testing

[detox]

I've said it before, but adding weight to lefthand side of hull will help UL-1 handle better (less chine walk). The steep 4 degree AOA helps hull be loose and fast down the straits. The excellent turn fin keeps boat planted in turns if adjusted correctly.


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[ronn25]

I've said it before, but adding weight to lefthand side of hull will help UL-1 handle better (less chine walk). The steep 4 degree AOA helps hull be loose and fast down the straits. The excellent turn fin keeps boat planted in turns if adjusted correctly.


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I will try this...seems I have to put a lot of negative angle on the strut to keep it from blowing over, but it slows the speed down. I had to add about 6 oz to my miss vegas because it would blow over above 45mph

[Capt. Crash]

I've said it before, but adding weight to lefthand side of hull will help UL-1 handle better (less chine walk).


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By left do you mean port side?

[detox]

By left do you mean port side?

Correct...lefthand side of boat as if sitting in boat and facing forward. Opposite side to turnfin side.

[Capt. Crash]

Hmmmm....I have more weight in the starboard side due to all the added glass of the turn fin/sponson repairs....I wonder if that makes my boat more prone to wobble?

I would think more weight in the turn fin sponson would help it plant better in the corners...but what do I know...it's my first hydro

What's the reason more weight in the port side sponson is better...counter acting prop torque?

[detox]

What's the reason more weight in the port side sponson is better...counter acting prop torque?

Correct.

The starboard side is held down with turn fin if adjusted properly...read manual.

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[Drag Boat Bob]

Hmmmm....I have more weight in the starboard side due to all the added glass of the turn fin/sponson repairs....I wonder if that makes my boat more prone to wobble?

I would think more weight in the turn fin sponson would help it plant better in the corners...but what do I know...it's my first hydro

What's the reason more weight in the port side sponson is better...counter acting prop torque?

It used to be that we ran left hand props because the driver sat on the left/port side (sorry, drag racing days again). This weight helped compensate for the counter-rotation "lift" of the prop torque and helped balance things out.

With added weight on the right/starboard side, it would be like adding to the counter-rotation lift, and could very well ADD to the torque roll and subsequent bounce.

I agree with Detox. Adding weight to the left/port side is the most logical when running left hand props. Also the bigger the prop, the more counter-rotation torque.

Currently, in the big boat world, this was cured by running twin counter-rotating props in TFH.

In my prop testing, I am finding that as I increase the prop size, the lift on the left/port side is greater. Only in absolute glass water is this not too much of a problem. With a slight chop things start to get hopping...

Then of course, I am still new at these rc boats...

[Drag Boat Bob]

Well, I have finished prop testing for now and here is what happened:

L40x57/3 - (GPS= 50.9 mph) I spent 2 hours re-sharpening and I think I got carried away since it looked a bit smaller when I was finished. It was so sharp you could shave with it. No more cavitation problems to speak of as long as you keep the speed up. This is a good prop.

m445 - (GPS= 51.1 mph) This is a wild ride. I could not keep it under control in the corners. It was out of control with ANY cross wind. Exciting, but probably too much for my setup. I do not understand why this prop was much wilder (and a bit slower) than the L42x66.

Bottom line with the props tested: I prefer the L38x63 as the best all around prop. Good speed and great acceleration.

Interesting finding: The more I tested the larger props the slower the boat went. The motor leads were up to 151 degrees (I may have a problem here). I think I will have to change to the bullet plugs.

I also have been testing flex cable lubricants (even mayonnaise) and have a lot more to do on this subject, but I can say that there is 3 to 4 mph difference here (another post).

[Brushless55]

Well, I have finished prop testing for now and here is what happened:

L40x57/3 - (GPS= 50.9 mph) I spent 2 hours re-sharpening and I think I got carried away since it looked a bit smaller when I was finished. It was so sharp you could shave with it. No more cavitation problems to speak of as long as you keep the speed up. This is a good prop.

m445 - (GPS= 51.1 mph) This is a wild ride. I could not keep it under control in the corners. It was out of control with ANY cross wind. Exciting, but probably too much for my setup. I do not understand why this prop was much wilder (and a bit slower) than the L42x66.

Bottom line with the props tested: I prefer the L38x63 as the best all around prop. Good speed and great acceleration.

Interesting finding: The more I tested the larger props the slower the boat went. The motor leads were up to 151 degrees (I may have a problem here). I think I will have to change to the bullet plugs.

I also have been testing flex cable lubricants (even mayonnaise) and have a lot more to do on this subject, but I can say that there is 3 to 4 mph difference here (another post).

Start the thread!

[longballlumber]

Well, I have finished prop testing for now and here is what happened:

L40x57/3 - (GPS= 50.9 mph) I spent 2 hours re-sharpening and I think I got carried away since it looked a bit smaller when I was finished. It was so sharp you could shave with it. No more cavitation problems to speak of as long as you keep the speed up. This is a good prop.

m445 - (GPS= 51.1 mph) This is a wild ride. I could not keep it under control in the corners. It was out of control with ANY cross wind. Exciting, but probably too much for my setup. I do not understand why this prop was much wilder (and a bit slower) than the L42x66.

Bottom line with the props tested: I prefer the L38x63 as the best all around prop. Good speed and great acceleration.

Interesting finding: The more I tested the larger props the slower the boat went. The motor leads were up to 151 degrees (I may have a problem here). I think I will have to change to the bullet plugs.

I also have been testing flex cable lubricants (even mayonnaise) and have a lot more to do on this subject, but I can say that there is 3 to 4 mph difference here (another post).

Bob,

Can you give us the rest of your set up:

Strut depth and angle
battery set up (mah, how many P)
Turn fin +/- angle

Thanks
Mike

[Drag Boat Bob]

Bob,

Can you give us the rest of your set up:

Strut depth and angle
battery set up (mah, how many P)
Turn fin +/- angle

Thanks
Mike

I think I have given this sometime back, but here goes.

Strut: 1" (dropped from the stock 7/8")
Strut Angle: Approx 1-2 degree negative angle. This is the way it came.
Batteries: (2) Max Amps 6500 mAH, 2S in series.
Turn fin: stock lower setting. I tried it raised to the next hole, but couldn't corner well.
Rudder: Removed lower bolt and used a Kintec nylon (thinner) shear bolt. This allowed for a few degrees of positive angle.

[longballlumber]

Thanks for your reply!!!!

[Drag Boat Bob]

Start the thread!

I won't be able to continue the testing for 3-4 weeks, but this should give me time to change the motor connectors to larger ones. Their increased temperature was not indicative of the other components.

[detox]

Octura x442 works verywell !


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[Drag Boat Bob]

Octura x442 works verywell !


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Aren't you running that NUclear power plant though?

Don't forget I'm running the stock spinner.