My Motley Crew Re-Build

[Fluid]

I received what was apparently a pre-production hull with hardware only. It was neither painted nor decaled, it just had the stock hardware. Unfortunately the tunnel floor was too thin and instead of being a nice flat, straight line from bow to stuffing tube it was deeply bowed. This would not work, so I cut out the inner hull tub, clamped the tunnel floor to a 1x4 wooden board and put down some carbon/Kevlar. This brought the bottom back to the designed shape.

I tore off the stock hardware and installed the SpeedMaster stuff from my MeanMachine, replaced the stock cable with 3/16” material in a ¼” OD brass stuffing tube, and glassed in some short G-10 stringers for the motor mount. When I tested the MC prototype I had great luck with the factory 1800 Kv motor, so it remained as did a spare AquaCraft 60 amp ESC (with monster cap).

I blueprinted the sponson bottoms and plugged the unused transom holes with epoxy. The cat runs great with an m445 prop, hitting high 40s easily and finishing a 6-lap heat in 100*F weather with nothing over 130*F. This is a fun boat which I'll race in the P-LOS class the club runs. It is much faster than my OSE-lay-up MeanMachine was with the identical parts.

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The boat with the inner hull cut out.
That is all the floatation I found inside.

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Overall layout after carbon/Kevlar.

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Front of the hull showing motor mount.

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Another view of front showing motor and ESC.

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Detail of aft end of hull showing servo mount
and carbon rod/silicone tubing used for pushrod seal.
The boat runs completely dry inside with the setup shown.




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[sanyijr]

Fluid,

Very clean! I like that alot.

Question: I have seen all the post on the capacitors on the ESC. What difference did you see in this setup from that addition? Major temp difference? Reason is, I have a stock motor, X640 s&b, 2 20C 5000 lipos in series and still getting pretty warm on the esc side of things (swordFish 120 V1 without logging). Boat is pretty loose. + 2-3 degree on strut and up almost 1/2" fron transom. Drive line is free. Just got 2 4s packs so i will be running in parallel. So I assume the 20C in series is not the best, but just curious if it would help my situation to add a cap of similar size and voltage...

[Fluid]

I blew the cap on my AQ ESC (one of the earlier versions with known-to-be too-small caps) so I just installed a cap I had handy. I see no advantage although it stays cool and there is always a spark on plug-in. The cap provides extra voltage when the packs cannot supply what the motor demands. Usually high capacity capacitors are used when the power wires are too long to ease voltage spikes.




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[siberianhusky]

Did the hull lose much stiffness when you removed the tub? I know you stiffened up the bottom. Was thinking about doing what you have done but was worried about weakening the hull.
Any added cloth on the sides?
Personally would rather have the open hull over the tub.
Thanks & cheers

[Fluid]

No loss of stiffness I could detect, but the cloth stiffened up the whole thing. Most of each side is double-thick due to a large overlap of the shoebox construction. The only cloth I used is what you see on the bottom. There may be variation in the thickness of the fiberglass on these hulls, that's why mine was so weak in the tunnel while others were not. But remember, this was apparently an early pre-production hull.



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[sanyijr]

I blew the cap on my AQ ESC (one of the earlier versions with known-to-be too-small caps) so I just installed a cap I had handy..

I figured that since that Cap is almost the size of the motor. :laugh: I figure i will try the ones Steve has here http://www.offshoreelectrics.com/proddetail.php?prod=ck-cap-35v-1000 .

I realize mine is not as big or long as yours (ha ha), but a little extra insurance I figure. In any case, thanks for the info. And the photos! Very cool mod!!!