Bob, I'm using two seven cell Duratrax 2500 NiMH battery packs connected in series for each motor. They are connected in series with that "Y" connector you can see in the image. The runs are 10 to 12 minutes long. I'm usually motoring along at 3/4 throttle. That was the setting I was using when Tom was shooting that video of my PT boats. Dan.
http://www3.towerhobbies.com/cgi-bin...&I=LXXUN9&P=SM

O.K., with 16.8V going to each motor that begs the question about your ESC's?  Since I run 12V SLA's (they're cheaper for me), my ESC's are also 12V, 50A w/BEC. 

Bob, here's the speed control I'm using;
http://www.astroflight.com/index.php...products_id=93
The motor is rated at 12 volts, typical, but will tolerate more according to Bob Boucher. I am never at full throttle at the start of a run. The combo has been working well for the past ten years with no signs of wear although they get pretty hot. I'm going to look in to a muffin fan like Tom uses to cool things off. Dan.

Dan,

Thanks for the information. Something for me to strive towards in the future (maybe). Astroflight is top of the line in my opinion but out of my price range. Sometimes, when you keep your eyes open you can find a good deal though.

Bob

Here's an image of the antenna mount. It is screwed in to a hardpoint of 1/4 inch plywood on one of the frames and is cut from 1/8 inch ply. In keeping with Futaba's instructions, the antennas are orientated 90 degrees apart. I still like the idea of keeping at least one of them vertical over the surface of the water. It should help with the reception during my trips to the other side of the lake. Dan.

If I may make a suggestion: To allay your fears of losing reception because you do not have an antenna poking out the top of the deck, you could just mount to the deck itself. Upside down under the deck of course. This way your antennae are always above water.

Tom, that's another way to do it. I failed to point out the the vertical portion of the antenna is well enclosed within the very spacious volume of the cabin. Dan.

Ah so. Perfect!

The last thing, the receiver battery pack is in. First some 3/8 plywood pieces were epoxied to a frame and the keel. A mount for the pack was screwed to the hard points with flat head sheet metal screws. Finally the battery pack is held in place with #64 rubber bands. Now, I have to continue coating everything with the finishing resin. Dan.

I had a full day of sun so I was able to stain and spray on four coats of clear. The dark stain color really got warm in the sun and cured all the coats in an hour each. Dan.

You want some sun and heat? Bring it to the Valley. 107°F in my backyard today.

Yeah, yeah. We just got a break from several days of 104 and 105 degree days - in Indiana! Now it back to pleasant 85 to low 90's.

You two are in prime areas to get your paints cured. I have to wait a while. I baked the stained surfaces in what little sun I had today and will start on preparing the rest of the hull for painting tomorrow. Dan.

I covered the bottom of the hull with ¾ ounce fiberglass cloth and some more Finishing Resin. The cloth was placed flat on the bottom and smoothed out. The resin was brushed on with an acid brush. It was then spread evenly with one of those small high density foam rollers. The good old sun accelerated the curing time. The excess was sanded off. The stained surfaces were protected with two types of tape in preparation to coating the sides. The main barrier is Scotch Fine Line tape. It is translucent green in color and is available from the auto paint stores. The blue tape is the regular painter’s low tack tape. The coating process was repeated on the sides. I’m just about through the second set of resin for this build.

Seeing the boat in the chair, I finally have a sense of how big this sum***** is!

Tom, a few minutes after that image was taken of the boat in the sun, the marine layer moved in and the temperature dropped precipitously. I had to bring the boat in where the house temperature was 75.

The Z-poxy Finishing Resin cured well overnight and I attacked it with 80 grit paper. It took a few hours until I had the surface defect free. I then had to remask everything, this time with paper also because I was going to do a lot of spraying. I use PCL 913 a lacquer based primer. Ever since these primers were banned for automotive use in the Los Angeles area, DuPont and PPG stopped shipping them here. Pacific Coast Lacquer is local and the only one available. A Devilbis Touch Up gun is used with the medium tip. 1 part of primer is mixed with 1.25 parts lacquer thinner. All spraying is done in the garage. The first coat was sanded with 150 grit paper, the second with 220 and the third with 400. All that fiberglass and resin really paid off because there was very filling to do. The surface is near perfect.

There’s nothing like Rustoleum for a good finish. Out to the garage again for a heavy coat of primer. Because it was foggy, I brought the boat in to the house where I have a dehumidifier going in order to reduce the humidity and raise the temperature. It was 76 degrees and 45% humidity. After an hour, it was out to the garage for a very wet coat of white. Back in the house for an hour and then to the garage for another wet coat of white. The sun did come out so I let each side soak in the sun for two hours. The paint was dry to the touch and I was able to remove all the masking material. The result was just what I was hoping for. I’ll let it dry for another day and then I’ll mask it off for the bottom paint. Dan.

Lookin' good!

Wish I lved on the coast!

Living by the coast has its advantages.

The bottom of the hull got the Rustoleum treatment after the white was taped and masked. The plans call for a bronze color. However, I had plenty of red so that's what it got. The plans showed the water line but it did not make sense. I had to scribe my own after proping up the hull and using the table top as a datum. Whos knows if it's right? Anyway, who cares. Dan.

Looks nice Dan! I have seen those bronze color bottoms and I think it looks funky. Red is much better.

Thanks Tom.

The porthole rims got a coat of Rustoleum primer and then chrome paint. Masking tape was pushed on to the inside edge of the rims. About 1/8 inch of Finishing Resin was poured in to the rims to simulate the window. It came out translucent, not really clear. When cured, they were epoxied in. Here's a shot of the completed assembly. All that's left is putting in the running gear. The red is still soft and I'll have to wait for it to harden until I can start installing the gear. I'm about a week away from the maiden voyage. Dan.

Those port holes look much better than the originally planned "black holes" 

Bob

Yeah, that's a heck of a cool technique there for the porthole glazing. Gotta file that one away!

Bob, we can all thank Tom for his insistence about the portholes. Dan.

I got the motors installed with the prop shafts and props. My three cell battery pack was used to get the motors turning to check the rotation. Every thing was smooth. The batteries were laid in place to check out the weight and I was amazed to see that it weighed a little over 13 pounds, maybe a little more when it's ready to go. At this weight it will be bobbing around on the surface like a toy. The CG was also a little further back than I wanted. I'll have to ballast it with four to five pounds of lead around the keel. Dan.