36 inch Hopper Tunnel electric conversion

[Modified RC]

I've had this boat for many years and used to run it with a K&B .45 nitro engine.
Now it's time for a brushless conversion!

Some parts purchased so far, all from OSE:

Motor-TP 4060 - 1650KV 6D

Battery-Revolectrix 6s 22.2V

ESC- Swordfish Pro 200amp

350mm long CF battery tray

The first step in the build was to cut the rear of the hull away to make room for a long radio box

[Modified RC]

Next was the radio box, I milled the box from a solid oak 4x4.
Bottom and outside milling in first pic.


Then in the second pic the inside pockets were milled out. The front pocket will hold a GPS speed unit, the rear pocket will hold the steering servo, and the center pocket will hold the battery.

[Modified RC]

Next I reinforced the floor of the hull where the cutout was made for the radio box, I used both fiberglass and CF cloth

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Radio box finished and coated with z-poxy finishing resin, lids for the 3 pockets were milled from .100 thick clear acrylic

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Radio box installed in hull but not glued in place yet, I think I will use silicone to glue it in place so I can remove it in the future if needed.

[roofintrash]

Is it done yet?
Nice work as usual brother.

[Modified RC]

With the original outboard mount, the prop would be too low in the water for electric use. So I made a new outboard mount that raises the prop up higher. I was advised to start with the center of the prop shaft 1/4 inch above the bottom of the hull.

[Modified RC]

For the steering I'm using .056 diameter cables instead of the solid rods, so I made a "wheel" to mount to the servo horn so the cables will work nice and smooth. The cable ends are bent at 90 degrees and inserted into the holes in the wheel, then a 3mm screw locks them in place.

[Modified RC]

Is it done yet?
Nice work as usual brother.

It's getting there

Thanks man, it's going to be a fun year!

[Modified RC]

I wanted 2 water pickups, one for the esc and one for the motor, so next was making a holder to fit 2 pickups, it's held in place by a 4mm screw. I drilled and tapped the original hole to 4mm

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Motor with the Hyper performance adapter kit installed: http://www.offshoreelectrics.com/pro...pi-eobck75-5mm

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That is where I am at so far, I will update the thread as I progress through the build.

All comments are welcome, especially any set up info on center of gravity, prop choice, etc

Thanks for looking , this is my first brushless tunnel conversion so.....

[Blandon]

Great job on the conversion so far. The Hopper's are great handling hulls. Radio box came out sweet. On my P-Limited tunnel I have my CG at 29% from the transom forward with everything in( battery etc. ) and the cowl on, the center of the propshaft is 3/16" above the ride surface of the sponsons with about 1 degree of positive angle and it drives and turns like it's on rails! Look forward to seeing your progress on this tunnel.

[Modified RC]

Great job on the conversion so far. The Hopper's are great handling hulls. Radio box came out sweet. On my P-Limited tunnel I have my CG at 29% from the transom forward with everything in( battery etc. ) and the cowl on, the center of the propshaft is 3/16" above the ride surface of the sponsons with about 1 degree of positive angle and it drives and turns like it's on rails! Look forward to seeing your progress on this tunnel.

Thank you for your response, I just asked you a question in your thread before I read your reply here.
That is great news on the CG, so far I should be able to adjust between 28% and 32% by moving the battery in the box. Also thanks for the prop height and angle info, I will be able to adjust to those settings with the mount I'm currently using.

[Modified RC]

I got my steering linkage all done, and the battery tray jb welded in the bottom of the box, I will get some pics up soon.