Boldly Going Where No Man Has Gone Before. RC Nano-Hydro

[emspjay]

Excellent progress and work! I really wanted to jump on this but I got way to many other projects to finish, and didn't want it to be a year after it was gifted before I started.

[Jerryemartin1958]

Keep going you got our interest stirred up. I like to scracthbuild and I am now thinking of building one from scratch.

[Dr. Jet]

Keep going you got our interest stirred up. I like to scracthbuild and I am now thinking of building one from scratch.

Take a look at my other concurrent thread. I'm going to do a 1/20 scale Atlas Van Lines Blue Blaster from a laser-cut kit I've drawn up in AutoCAD. It won't take all the special machine work that this little beast will; it should be doable with off-the-shelf parts. I'm taking the wood to the laser guy tomorrow to cut the first prototype kit.

[Dr. Jet]

I'm at a bit of an impasse on this project. I need to have the motor in hand to do a parts layout and make the driveshaft, but it is literally on a slow boat from China.

[Dr. Jet]

Good News, Bad News

I have been in contact with Chris Casper, the designer and builder of these hulls. It seems he made this particular hull with three different thicknesses of material. 0.020", 0.030" and 0.040". The 0.030" was popular with the racers as it was lighter, yet rugged enough and provided improved performance over the heavier 0.040" material. My hull is made from the 0.040" sheet. While that means it's only about 5 grams heavier than a lighter version, it is still 5 grams.

The racing rules for the free-running boats called for no major sanding on the hull. Since this is a "No Rules" project, maybe I can sand a gram or two off and compensate for the slightly heavier hull.

[Dr. Jet]

Well, the motor has finally arrived. I checked out the motor coupler I made earlier, and due to the run-out in my old lathe chuck, I was not happy with the alignment of the motor shaft and the drive shaft in the coupler. The mis-alignment was only about half a thousandth, but it was there nonetheless. When my new chuck arrives, I'll make a new coupler.

In the meantime, I'll do a parts location and make a motor mount. On that line, this motor has some REALLY TINY mounting screws. I've ordered screws and will be making an uber-tiny CF motor mount and rear motor support in the near future. Stay tuned and bring your magnifying glasses.....

[Dr. Jet]

Parts Layout

Now that I have all the major parts, I can do a layout. I need to be able to access the motor, the coupler, the servo and the receiver for removal and replacement. Furthermore, I need to have it balance somewhere just beyond the aft end of the sponsons and make battery replacement easy.

Here's what I've come up with. I may solder the servo and ESC leads directly to the receiver tabs and eliminate the bulky plugs. I also plan on soldering the motor leads directly to the ESC board.

Current weight of everything in the photo plus the rudder, cowl, and motor: 69.5 grams.

[emspjay]

This is so cool! Great work!

[Dr. Jet]

I made the servo "tray" tonight.

[Dr. Jet]

I mounted the receiver with a couple of small pieces of styrene angle (it just slides into place), I've soldered the motor directly to the ESC and added the appropriate battery plug. Wire runs are kept as short as possible for weight concerns. Additionally, the receiver cover, ESC cover, and connector covers have been removed to save weight and space.

[Dr. Jet]

I thought some flotation might be a good idea....... Just in case. The sponson foam is 0.87 grams. Once the motor is installed, I'll add some in the center section as well.

[Dr. Jet]

One of the more challenging aspects of this build is the accessibility of the various components. I want to be able to install and remove all of the major components of this boat once the hull halves have been joined. It will take the dexterity of a surgeon, but I can install the Rx, the ESC, the servo, and the motor through the two rather small openings in the deck. The motor will be moved forward about 1/4" from where it is in the photos and the center flotation will be relieved accordingly.

[emspjay]

Wow! Again great work! I like the penny next to stuff for reference, it is smaller than I thought it was. When Jim started a thread last year about R/Cing one of these I suggested maybe using one of these little Venom boats I purchased as a donor. Not sure that would work anymore (going to post pics), you have done a great job selecting everything that will fit that hull!

DSCN2678.jpgDSCN2679.jpgDSCN2680.jpg

[Dr. Jet]

A Hundred Times Better Than a Penny

This really shows off the diminutive size of this little hydro.

[srislash]

Awesome work, I really can’t wait to see
This go. I have been thinking of a micro for some time and now here you and Paul are giving her.
Shawn