Newbie with tunnel hull project

[HTVboats]

Very good info. 42X55 Grimracer is the "bread and butter" prop on a spec tunnel. As for a water jacket without a cowling over the motor you have plenty of airflow on an outboard. I have run without which will let the ESC have more flow and saves weight. Cooling in series you have warmed water going to whichever is last on the pipe. I use a "T" and split flow of cool water to both when cooling the outboard motor with a water jacket. Check after run temps for sure. When we run road course cars I see motor temps above 150 degrees all the time without damage. Never had an outboard come in that warm.
Mic

[HANNlBAL_KING]

42x55 Grimracer prop, leopard 3660 motor, and water jacket ordered. I will play around with and without the water jacket to see how I want to run it.

I'm finally going to get a bit of time this weekend to work on the placement and mounting of the hardware. Once I have it situation and the boat balanced I will tear everything down and start painting. I'll be sure to post up pics as I make progress on it.

[HANNlBAL_KING]

When the rest of my equipment shows up I will mount the lower unit and motor to start working on the balance of the boat, but here is the tentative placement of electronics.

2016-06-17 08.13.31.jpg

I'm also going to think through a way of waterproofing the section where the battery and ESC are located.

[HOTWATER]

You are gonna want that 4S pack in the back...esc on top of the lipo or just ahead of the lipo...trust me...

You may have to make longer esc to motor leads and a 6"or 8" servo extension wire for the esc to receiver...drill a hole from mid box into front box as low as you can to run the esc extension wire to plug into rec.

Also, you will be well off using a "push/pull-push/pull" system for steering using 4 -4/40 rods, two on each side doubling them up and using small wheel collars to lock the doubled rods together at the correct lengths. This double control horn : http://www3.towerhobbies.com/cgi-bin...?&I=LXFVJ9&P=M

I use these redline seal mounts and seals for steering rods...(they should work great coming out the back of your forward radio box!)

http://www.shop.redlinemotors.us/Pushrod-Seal-Mount-1-RLPM-RPS.htm

http://www.shop.redlinemotors.us/Pushrod-Seals-RLPM-PRSS.htm

[HANNlBAL_KING]

In researching where the COG should be it appears that around 28-32% of the length of the hull from the transom. If that is correct the battery will need to remain where it is currently and I will actually have to put the ESC up in the front compartment. Does that seem right?

[HANNlBAL_KING]

I have only been able to work on the boat a little bit at a time on the weekends, but here are a few updates:

Float test after finding COG
2016-06-25 09.45.59.jpg

Building battery tray mounts
2016-07-02 19.12.17.jpg

I will be running power and cooling lines underneath the battery tray
2016-07-02 19.28.27.jpg

Building bulkhead wall between front and rear water tight compartments
2016-07-06 19.26.33.jpg

I am hoping to make some more progress on it this weekend.

[HANNlBAL_KING]

I've been making some progress today. Here are a few pictures of test fitting components before I begin to epoxy things in place.

Electrical and cooling lines running under battery tray (Battery tray is removable)
2016-07-09 11.25.33.jpg

Battery placement (can move forward or back to find COG)
2016-07-09 11.26.28.jpg

Test fitting placement for bolts to be used for closing the center hatch
2016-07-09 11.59.14.jpg

The rear section of the hatch will be permanently affixed and will have the power wires for the motor along with the intake and exit for the cooling lines coming through it.
2016-07-09 12.50.48.jpg

[HANNlBAL_KING]

With all of these changes the boat is gaining a bit of weight. Once I am done I believe it will end up weighing about 10oz more than it did with the gas engine and the fuel tank being full. At first I wanted to keep it as light as possible, but thinking more about it I like the idea of a heavier and more stable boat. If I get the bug to go faster I will build something from scratch with speed in mind.


I've decided the rear hatch will also be removable to make it easier to service.
2016-07-09 15.12.10.jpg

Just a few pictures of the hatches on.
2016-07-09 15.46.30.jpg

2016-07-09 15.46.41.jpg

I'm off to the hobby shop to get some more parts.

[HANNlBAL_KING]

I've been working on other projects around the house over the past few months, but finally found some time to work on the boat again.

I've spent most of the weekend priming, sanding, and painting the boat along with polishing the cowl to get it looking better. I still need to wet sand and polish the boat itself once the clear coat completely cures, but I got pretty excited about how it is turning out and wanted to share a few before and after photos.