Venting UL-1 sponsons

[properchopper]

[Having not received any feedback/ridicule on this mod in another post, I'm re-posting it here]

With the UL-1 running rather nicely with the Scorpion 1900 KV; the sponson dance still was bugging me. I reduced the AoA some with ride pads, and vented the sponsons and added air-dam strakes to reduce the air-pack which, in theory at least, may contribute to the dance. I'm also using some ballast inside the sponsons-outboard of the roll center. If the death wobble continues to persist, a de-commissioning ceremony will follow, employing the use of my best heavy duty engineer boots

[teach]

I was staring at the one I just got and would have to agree with the AOA theory. I wanted to give it the whiplash idea with one side at 0 dihedral too.

Biggest problem I am having is I look at stuff to long then never do anything due to my mild ADD behavior.......ooo that cloud looks like a snowman.

[properchopper]

I was staring at the one I just got and would have to agree with the AOA theory. I wanted to give it the whiplash idea with one side at 0 dihedral too.

I'm heading to the lake to test today. I'll let you know if this helps...


Biggest problem I am having is I look at stuff to long then never do anything due to my mild ADD behavior.......ooo that cloud looks like a snowman.

I understand completely. At my age my memory is... Uh, what were we talking about ?

[JimClark]

My guess is that the air dam would be a better solution.

Jim

[chummer]

If the death wobble continues to persist, a de-commissioning ceremony will follow, employing the use of my best heavy duty engineer boots

Will you video the ceremony?lol

[properchopper]

Results : Motor : Scorpion 3026 1900 KV . First run with M445 : [smooth water] - Drastically reduced wobble. Bobbled slightly crossing wakes, but controllable. Second run with hub-cut X442 : tiny chop - 8 oz. inside left sponson - slight wobble across wakes but settled nicely and am satisfied. Boots will stay in closet. Right turns with weight inside L sponson weren't as smooth. Will center weight. BUT GET THIS !! : after 3+ minutes, SC 105 deg, Batts 112 deg, motor 248 DEGREES !! Ouch !! Too weird but spec'd to 395 deg or something like that. Yikes !!

[chummer]

proper, Did you GPS this setup?

[Rumdog]

My little 400 size outrunners get SUPER hot also. Power never seems to fade though. I think they can handle it.

[properchopper]

proper, Did you GPS this setup?

No, but with the X442 I estimate mid-forties. Since the boat's now holding on to the water better, I'm reducing the ballast & propping down- just installed a Grim 40/53 & We'll see what happens. For LSSH Spec racing, I'll go back to the UL-1 motor & prop to finish the race, not top speed.

[detox]

The UL-1 motor will run lots cooler. The Grimracer L40 x 57/3 prop will be fast and a little more stable. Use lighter weight lipos...I use two Hyperion 25c 5000mah packs. Add A little more weight to outside left sponson (stick on lead).

Try a reverse rotation prop such as the Octura x442r without lead ballest on left sponson (you will need wire drive or reverse rotation cable, switch motor leads)?

...

[Rumdog]

Reversing the prop rotation would cause theright sponson to lift in turns. Not what you want!

[detox]

If adjusted correctly turn fin will hold down right sponson.


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