New guy 1/10 Cracker build

[Shawn Wittenbarger]

Hey everyone, Im Shawn, New to rc boats, but not rc, I currently have an Axial SCX10, and a Blade 400 3d.

Anyways Ive been looking for more of a challenge lately and set out designing my own 1/10 Cracker, based on the hull stations of the full size boats.

I plan on ditching the straight driveshaft for a flex/strut setup as this will be a fun build for me and a couple of friends.

Im just caught up in how to properly spec the hardware. Ive gathered I should be running a 30 something mm prop based on what comes in the vac u cracker kit, but Im unsure of my target power level, 300? watts.

So Im asking for a 18.5" Crackerbox style boat running 3S(already have 3S 2000's) what would you experience guys pick for the power train as far as motor/flexshaft size/prop selection?

Ive browsed OSE's hardware and was planning on the combined micro strut/rudder for 1/8 shaft.

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[Shawn Wittenbarger]

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Progress is slow due to work, but the major formers are sorted, now to finish adding notches and building aids into the formers.

[Shawn Wittenbarger]

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Getting close to cutting wood, only have a couple more notches for some of the formers, then to add tabs for offset from a building board. Working in a craft store that stocks a large selection of Balsa and Basswood lit a fire to get it done. I'll be working there all week, and purchasing the wood in the next day or two.

[johnnyb5.0]

try the atomic 2200 kv motor and speed control out of the whip lash. I'm running it an old dumas ski-vee on 3s and i'm running 30 mph with an almost flat bottom 18 inch long boat. the hardware I am using is stuff I scrounged up from pro boat and aquacraft models of approximately the same size with an ose .098 flex cable and matching collet. good luck with the cracker box they are a wild boat

[Shawn Wittenbarger]

Thanks Johnny, the motor ive picked at the moment is a 2208 outrunner, 160w continuous, 220burst, and 2600kv, hopefully its has enough wattage to turn the prop at the motors full potential.

In other news I went on a cutting/gluing spree yesterday(12 hours), and this is where I got. Picked up some aerosol Thompsons water seal and applied a coat to the inside of the bottom half of the hull today. Gotta love work trips with nothing better to do on the weekends.

I used basswood for the transom/bulkheads stringers and keel pieces. Sheeted with 1/32 balsa.

As can be seen in the cad drawings above and whats been built, with the exception of the rear and front of the hull ive removed every other bulkhead. If I had to guess the hull is 4oz max at this point.
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[johnnyb5.0]

looks good

[Shawn Wittenbarger]

Placed the order for hardware today. Ordered almost all of the hardware from OSE. Got the combined micro strut/rudder + flex cable and stuffing tube. Ordered the motor to flex coupler, watercooled motor mount, as well as an assortment of props. I ordered a 450class turnigy outrunner 2500kv 400 watt, a proboat 40amp watercooled esc, and misc other odds and ends to finish it up.

[Shawn Wittenbarger]

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[Shawn Wittenbarger]

After a little morr planking/sanding and then filling and sanding the weight sits at 96grams, was 86grams before filling/sanding. Im now starting to lay cloth on the hull, picked up some 2oz/yd cloth and some 3m/bondo polyester resin.

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[Shawn Wittenbarger]

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After getting put off by other projects, I started getting some paint on the hull today. I have to let this dry, then mask and paint the bottom.

Sometime this week I will start mounting all of the hardware.

[Shawn Wittenbarger]

Got the combo strut/rudder mounted, time to place motor mount and install the stuffing tube.

[Shawn Wittenbarger]

CA'd the motor mount in place, and got the stuffing tube bent. I need to pick up some epoxy to permanently mount the motor mount and stuffing tube.

[johnnyb5.0]

looks awesome

[Shawn Wittenbarger]

Thanks johhnyb.

It floated for the first time today, was positioning electronics for balance. I currently have epoxy drying on the rudder servo mount.

To get the boat running I need to get all electronics mounted, build/mount a battery tray, and setup the rudder linkage. To fully finish the boat after that, I just need to build a hatch cover.
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[johnnyb5.0]

looks pretty awesome