37" Fightercat Daytona Build

[dag-nabit]

PART 1

Ok, before I start I want to be certain to give credit where credit is due. I received this Fightercat hull partially finished. The stuffing tube, strudder, servo mount, and motor mount, were already installed, and the hull was painted.

This is my first foray away from RTR, so it was a relatively easy step toward moving into the next phase of FE boating. More of a plug n play than a real build, but I did have to install the remaining hardware, and a few minor mods were necessary.

I choose to go with a Turnigy T180 ESC, Leopard 4082 1500kv, and Spektrum MR3000 rx for electronics, and plan to run 6S.

The first challenge I ran into was fitment of the motor. The 50mm long water jacket just fits between the front and rear mounting brackets leaving very little room for front/back adjustment. The water jacket was binding on the hull near the front bracket and I couldn't lower the rear of the motor enough to align it with flex shaft.

Water Jacket Contacting the Hull


I wasn't certain how to correct this. First I thought about putting a 40mm long water jacket on, but I wasn't enthusiastic about reducing the cooling area, the 50mm jacket only covers about 60% of the can as is.

Ben at Fightercat recommended beveling the edge of the water jacket to fit. I was nervous doing this, thinking I was going to grind through the o-ring groove, but I proceeded slow and easy, checking the fit often.

Beveled Edge on Water Jacket


As I continued to increase the width of the bevel it was still binding, so I smeared a bit of paint on the hull to find out exactly where the water jacket was making contact. Turns out that once the jacket was starting to clear the hull, the front end cap of the motor was also starting to make contact.

Both Motor and Water Jacket Contacting Hull


I eventually ended up grinding the entire "collar" area almost flush with the middle section of the can. But still had to solve the problem of the motor contacting the hull.
Water Jacket "Collar" Ground Almost Flush with the Body Section.


I decided it was time to go for broke and applied two layers of fiberglass and resin to the bottom of the hull underneath the motor mount area. I sanded and painted the patch, then used a Dremel cutting tip to carefully etch out a small "belly pan" under the motor mount for more clearance.

Not sure if this is a common solution for this problem or not. Seems obvious this motor mount is intended for 36mm motors.

Fiberglass Patch Applied


"Belly Pan" in Hull Underneath Motor Mount


TO BE CONTINUED

Kevin

[Rumdog]

The easy solution would have been to remove the mount, and make small blocks for the CF mount rails to sit on and raise it up off the hull a bit.
Or, use a different mount all togrther.

[sailr]

The easy solution would have been to remove the mount, and make small blocks for the CF mount rails to sit on and raise it up off the hull a bit.
Or, use a different mount all togrther.

but you had already glued the mount in I take it? Test fit, Test fit, Test fit and then glue! Kinda like measure twice cut once. We've all done it! Don't feel bad!

[tiqueman]

The easy solution would have been to remove the mount, and make small blocks for the CF mount rails to sit on and raise it up off the hull a bit.
Or, use a different mount all togrther.

Yup

but you had already glued the mount in I take it? Test fit, Test fit, Test fit and then glue! Kinda like measure twice cut once. We've all done it! Don't feel bad!

He got it w/ the mount already installed from Ben.

[Boaterguy]

[dag-nabit]

PART 2

I needed to install the rear latches for the hatch cover, but also wanted to fashion some sort of clip to secure the front of the hatch.

I scrounged around in the garage and found a metal bracket that could be bent to suit the need.

I glassed it onto the underside of the hatch and painted it.

This is utilitarian, it ain't pretty, but seems strong and it works. I tape the hatch down as well, but I like the hatch to have the ability to stay in place even if it isn't taped down.

Front Clip Installed and Painted




After that it was a matter of installing mounting plates for the ESC and Rx box, drilling and installing the bulkhead fittings for the water cooling, and connecting the rudder linkage.

I opted for a "waterproof" Traxxas Rx box with an antenna stub on the outside.
and also installed a short antenna on the rear deck. This gave me mounts for both antenna wires off the MR3000 Rx.

Not certain this would be considered "optimal" antenna placement, but both are above the water line, and on my first (and only, so far) run I was able to run the boat far enough away that I couldn't see how it was behaving on the water. So it seems to work.

Not The Best Pic, But You Can See the Antenna Stub Just Inside The Hull, and On the Rear Deck.


So to recap quickly:

This is How I Received The Boat (Except for The Motor I Set In Place Before Taking The Picture)


This is the Boat With All Components Installed, Wiring and Cooling Done.




Kevin

TO BE CONTINUED

[sailr]

Yup



He got it w/ the mount already installed from Ben.

Aha! Shame on you Ben!

[sailr]

She's suuwweeeeet! Let us know how she run!

[dag-nabit]

The easy solution would have been to remove the mount, and make small blocks for the CF mount rails to sit on and raise it up off the hull a bit.
Or, use a different mount all togrther.

Thought of that. Being new to this build thing, I wasn't confident in my ability to cut out the existing mount, and then get another one installed and aligned properly. Maybe on the next one if I run into this again sometime.

Sometimes best to be a chicken sh*t the first time

Kevin

And yes, the mount was pre-installed when I got the hull. Which is not to say I wouldn't have really messed it up if I had done it myself.

[tiqueman]

lookin good Kevin. Keepin it clean, very nice.

Just an FYI, its not necessary to split the inbound water line and branch it, but I like your thinking. Most will run to the ESC first, then hit the motor, then out the boat. Im running two boats w/ leopards and that mount, one of which goes esc, motor, motor mount and out and it runs cool. Another I have two pick ups in the hull and cool the motor and esc seperately. ( My Genesis was set up that way as well) A member at the local club runs his Genesis at about 60 and does not run water thru the motor mount portion at all. 6S Castle 1520

[LarrysDrifter]

Ive found that using the water cooled mount in addition to the normal cooling system does absolutey nothing. Temps dont get any lower. To each his own, but Id rather not use the mount for cooling as it just creates another restriction for the water to flow through with out actually dropping temps. Just my opinion.
Good job on the boat. Im sure she will be fun to run. Maybe on your next build you can move the motor forward and bring the stuffing tube into the hull more with a bit more bend at the motor end and you will be able to use the angle adjustements your mount has to offer and not have to grind anything. The good thing about the Genesis/Daytona hulls is that the tunnel floor is an angle with the lowest portion in the center shaped like a "V" giving more room for motors and jackets.

[dag-nabit]

I know there isn't a need to run a Y splitter, I just like the idea of cool water going to both components. I'm also aware that if one loop has more restriction than the other the water will take the path of least resistance, which can prove to be problematic. I monitor my temps closely for the first several runs.

This is the first water cooled motor mount I have owned, and I questioned the effectiveness of them simply looking at the design, but I figured what the heck, I will give it a go and see what happens. Easy enough to bypass it if I decide it isn't worthwhile.

Kevin

[dag-nabit]

Part 3

The 4mm drive line that came with the boat really does nothing for me. They may be an OK setup but I guess I'm spoiled with the one piece drive systems that are simple to remove the cable for greasing and inspection.

Thanks to HydroJerry I have a strut on the way that has been drilled out to fit a 3/16" stub shaft, and I have a .150 flex cable with 2 1/4" x 3/16" stub shaft that I want to try eventually.

But the opportunity presented itself to try running last weekend so I decided to give it a go on the the stock drive line.

I'm new to cats and was uncertain on the best way to set things up, but figured I would get it dialed in sooner or later.

I'm sure I was no where close to being properly set up, but the boat was still pretty amazing.

Running a Prather S225 prop on 6S the boat will literally leap itself out of the water if I punch it too much on the hole shot.

I never did get it up to WOT, it was prop walking the boat into a spin at high speed. After doing some checking here on OSE, I realize I had the strut set too low. Next time out I will set things according to what seems to be the recommended initial set up, and start from there.

I flipped it a couple three times and on the last ditch both battery trays broke free, it landed right side up, and as I was running it in closer to me, the LVC cut in. So I'm looking at some repair time after my first run before I can go again.

Managed to hit 81kph (50mph) on the eagle tree gps, with a poor trim setup, this is promising, I like it.

I took some pics of the motor and ESC temps, but can't locate them at the moment. If I recall correctly, the motor was at about 35*C (95*F) and 40*C (104*F) on the ESC. Which seems not too bad.

I hit some pretty good amp spikes, in the 180 amp range, not sure if this would be normal on this set up, or possibly caused by having too much negative trim on the strut, Something I will continue to monitor on the next few runs.

While I'm repairing the battery trays (any suggestions on a good tie down system without trays??) I think I might put some extra fiberglass reinforcement on the motor mounts, and hopefully I will have the strut from Jerry by then so I can try modding the drive line.

Eagle Tree Data from First Run




Kevin

THAT'S ALL FOR NOW

[GP73]

While I'm repairing the battery trays (any suggestions on a good tie down system without trays??)

I just removed the trays and put a 2" wide velcro on the bottom of the hull, you can find it at Fabricland for $5 a meter.

[dag-nabit]

I just removed the trays and put a 2" wide velcro on the bottom of the hull, you can find it at Fabricland for $5 a meter.

I was thinking of that, pretty much the same set up as in my SV27's. But because I'm expecting this cat to hit speeds in excess of 60mph I would like to have additional velcro straps to hold the batteries securely, or some other innovative way to tie them down.

Kevin