Need HELP to NOT sink an upgraded old RC Boat

[Penguin Fart Racing]

A friend gave me an oooold speed boat. ( FIRE HAWK; OK MODELS / TAMIYA ). I gutted it and am in the midst of replacing its' MABUCHI RS540 SH ( no load 23500 rpm ) with a water cooled TRAXXAS STINGER ( ~29000 rpm ). TRAXXAS NAUTICA ESC, 2075 waterproof steering servo, 6519 reciever and 6s NiMH will replace to vintage electronics . Rudder was smashed so I made a new and longer one out of soldered sheet brass and brass rod stick. The stock trim-tabs and turn vanes came from my SPARTAN upgrade. With the bow facing forward, the battery box is on thevrear left, while the reciever, ESC, and steering servo is rear right ( see PIX ). One thing concerns me. I know about balancing and wing loading for aircraft and how to check aerodynamic stability for rockets. How should I check to make sure this build will run stable at speed, not roll over or imitate a submarine that does not sink ? How much free-board ( gunwal clearance ) should I have ? Should I add some weight to the bow to keep it from flipping over front-to-back ? Have not given her a name yet; maybe ANGELIQUE, or AMPHRITITE, or maybe the Melmacian Sea Goddess GLUB-GLUB ( think ALF ). THANK YOU !

 

[tntpoof]

use a small amount of Loctite foam in front of hull maybe 2 x 4" (below water line)no need to add weight as you will have surface tension holding boat to water . might add a single strand of 550 white string like 15'( help if it sinks)

 

[Penguin Fart Racing]

use a small amount of Loctite foam in front of hull maybe 2 x 4" (below water line)no need to add weight as you will have surface tension holding boat to water . might add a single strand of 550 white string like 15'( help if it sinks)

Thank you! Plan is to do these things and a test float in my bath tub before I break a bottle of fermented garlic wine across her bow prior to a sea trial ( er, pond trial ). Will do follow-up vids of throwing up some rooster-tails and she is high and dry on her stand at home I know about the AMYA ( https://www.theamya.org/ ). Can you recommend a similar group for power boats please ?

 

[tntpoof]

i think you better go with a airplane bottle my local liquor store has a giant amount of them id stay away from the mini skull head....i have no idea as to a powerboat club or whatever. many many years ago you could see places to run your rc boat they had floating docks put out in the water id say 100' x 200' those have disappeared same a rc air fields by me 9indian city. detroit rc boats on belle isle)

 

[Penguin Fart Racing]

Thank you for your input. I especially appreciate your patience with a noooooooob like me. There is just so much to learn and my projects sometimes are just trash and end up in the circular file . That boat is +99% done . I should find time for a shake-down cruise in a week or so. Newest PIX is attached. Cheers .

 

[burnskevin58]

A friend gave me an oooold speed boat. ( FIRE HAWK; OK MODELS / TAMIYA ). I gutted it and am in the midst of replacing its' MABUCHI RS540 SH ( no load 23500 rpm ) with a water cooled TRAXXAS STINGER ( ~29000 rpm ). TRAXXAS NAUTICA ESC, 2075 waterproof steering servo, 6519 reciever and 6s NiMH will replace to vintage electronics . Rudder was smashed so I made a new and longer one out of soldered sheet brass and brass rod stick. The stock trim-tabs and turn vanes came from my SPARTAN upgrade. With the bow facing forward, the battery box is on thevrear left, while the reciever, ESC, and steering servo is rear right ( see PIX ). One thing concerns me. I know about balancing and wing loading for aircraft and how to check aerodynamic stability for rockets. How should I check to make sure this build will run stable at speed, not roll over or imitate a submarine that does not sink ? How much free-board ( gunwal clearance ) should I have ? Should I add some weight to the bow to keep it from flipping over front-to-back ? Have not given her a name yet; maybe ANGELIQUE, or AMPHRITITE, or maybe the Melmacian Sea Goddess GLUB-GLUB ( think ALF ). THANK YOU !

Center of gravity for Deep V is 30% measured from the rear.
To adjust the bows ride when turning,
The fore or aft angle of rudder will effect the bows ride height.
A rudder that's kicked back will force the bow down, a rudder that's kicked forward will raise the bow.
This is why outboard tunnels slam down in turns, it's because of the leading edge of the rudder slops back. Same principal applies to deep vee boats, although not as aggressively.

Longer rudder might be bad as longer rudders can barrel roll a deep vee.

Sinking, if you can separate the top from the hull, place foam or styrofoam up front. Do not use expanding foam.

Turn fin you only need one on the right side of the transom. Boats turn left really well but loose grip (prop walk) turning right.

Offsetting the strut to the right slightly from center helps with chine walking and toque roll.

Trim tabs should always be level to the hull, never used to control the plane attitude. Prop angle is how to control the plane.
The closer the prop is to the transom the more stable the boat will ride the further back the prop is the looser the rear of the boat will be and spin out easier. This is why we run trim tabs, to get wet surface closer to the prop more or less hull extensions.

Never swim for a boat if it stops in the water no matter how good of a swimmer you are.
Buy a fishing reel Zebco thumb and a tennis ball sized rubber ball.
Hook ball to 20 pound fishing line.
Throw ball over boat and reel in slowly.

Lastly it's not a aeroplane.
Forget everything you know about airplanes. Nothing applies to boats.


Good luck.