This build will be a fully functional R/C Disney Nautilus when completed (soon!). The hull is a Custom Replicas 66" kit that was a mis-cast that I managed to trade for. There are a few flaws in the casting that made it unsuitable for a display model, but for R/C its wonderful!
This build will feature a gimbaled propeller for pitch control as well as a beautiful pump-based OTW dive module. A bow thruster is also going to be tried to be incorporated.
Both the OTW Dive Module and hull kit are available from me through my site at www.nautilusdrydocks.com.
March 25, 2011
I began this build by working out the complicated gimbal mechanism for the propeller. The prop is built onto a swivel mounted at the extreme aft of the hull. A brass bushing secures the prop shaft. The tilt bushing is made from Teflon and allows easy rotation of the shaft with no binding.
Twin brass arms lift the tilt bushing up and down, and the arm will be connected to the pitch control servo in the Dive Module.
March 25, 2011
My next task was to address how I would split the hull. I elected to try something new and cut the salon surrounds along the lower shroud, making the entire salon extension a single piece. This makes hull alignment trickier, but will make for a much easier access to the interior.
The cut was made with my trusty Dremel. The result was actually better than I hoped for. There is a gap that ranges from 1/16" to 1/32", but it will not be visible from more than a few feet away, particularly after the model is painted and weathered completely.
April 5, 2011
I moved onto modifying the solid resin wheelhouse floor for R/C use. I cut out the heavy center sections, leaving a framework of resin in place. Between that I adhered brass mesh for the floor. This will make the wheelhouse insert lightweight and allow air and water to drain from the wheelhouse quickly. The overall effect is very good.
At this point I also added the wheelhouse detail pieces to the wheelhouse itself, painted it up and secured it permanently to the upper hull. LED lights were put in the alligator eyes and bright green LEDs to the wheelhouse floor.
April 10, 2011
A big work day on the boat! Lots got done!
I secured the upper tail section to the lower hull, mounted the rudder and secured it all in place. I also added the side keels, modifying them so that they allow for the upper hull to slip on over top of the lower.
WTC saddles and interior bulkheads were put in place to keep the hulls in shape. They are fabricated from solid plastic and adhered with Bondo to the hull. Once the hull is complete, the interior will be painted matte black.
Orientation pins were added to the aft end of the upper hull to keep in in line with the lower while the top is being put on. I fabricated a retention pin out of the forward ram that threads through a collar in both the upper and lower hulls. It holds the hulls tightly together in alignment and turns a feature of the real boat into a manner of securing the hulls together without the need for extra bolts, screws or tools. I'm really happy with how it turned out!
Lead shot was added to the keel of the boat for ballast. I like putting in a fair amount to counteract torque roll from the big propeller. This lead will be offset by foam high at the waterline. The shot was sealed in the keel with resin and drainage holes drilled to let the water drain from the model when its pulled from the water.
The ballast grates in the bottom of the boat were all opened up and will be functional to let water in and out of the hull quickly. Similarly, the deck grating openings were cut open to allow for the venting of trapped air (and to help realism!).
April 11, 2011
Here is the beautiful Dive Module that Bob Dimmack sent me for this build. It features acrylic tubing, bellows seals for the linkages, and a wonderful pump-based ballast system that requires no liquid air to run (unlike a lot of my previous builds).
Unfortunately the pump area cylinder wall was cracked during shipping, however Bob promptly shipped me out a replacement section at no charge.
The beauty of this system is its modular construction which allows for easy access to the internal components and replacement of any damaged parts.
April 19, 2011
A week's worth of progress!
I've tested the WTC and it works wonderfully! I have a very minor leak at the forward seal. There may have been a piece of debris against the o-ring. I'll check it out but I'm not worried at all. The pump ballast system works great and I'm very impressed with it. It fills and empties very quickly and allows for very precise control of ballast amount.
I have elected to add a crew to this R/C Nautilus. I chose to put Nemo at the helm with a crewman beside. Conseil and Arronax will be in one of the salon windows and Ned Land in the other. This is in reference to the point in the movie just after the ship was rammed off of Rura Pente. In order to get Nemo into his driving duds, I had to do some creative body switching. He now sports Ned Land's old legs and a crewman's upper torso. Ned now has the crewman's legs.
The inner surrounds were added to the salon exterior and really clean up that area. The LED lights were added to the hull. Huge 10mm LEDs were put in the big floodlights. I'm anxious to see how they look behind the lenses.
My bow thruster dry box was completed and finished with a clear plexiglass lid. The bow thruster was installed as far forward as I could get it. Fortunately it aligned perfectly with my box for the drive shaft. Testing on the bench shows that it spins very freely with no slop. What I'm going to do is run power leads to the aft end cap of the WTC. The bow thruster has its own ESC which will allow slow speed turns without the model pitching about when the thrusters are suddenly clicked on.
The detail pieces such as the cleats and lower hull bits and pieces were added. The ballast grates now conceal the eight large openings that I cut to allow for drainage and flooding of the hull. Drainage holes were added to the lower hatch area as well as the keel to make sure that water is not trapped inside after the model is brought ashore after a run.
The upper deck was also cut open underneath all of the deck grates. This will allow trapped air to easily escape from underneath. Vent holes were also drilled just under the mounting flange for the upper raker arch which will allow trapped air to vent from the wheelhouse.
I have made allowances for the insertion of a clear plastic rudder extension that should disappear underwater. In my experience, this extension will halve the turning radius of the boat. If the model is to be displayed either ashore or at home, the extension is simply friction fit, so it can be pulled free and stored for future use. That, in conjunction with the bow thruster, should allow the Nautilus to cruise in very confined waters, if necessary.
The last thing that I've done to date is spray the inside of the upper hull matte black. This cleans up the look of the boat a lot. My LED driver board will be installed tomorrow morning.
April 24, 2011
Beauty progress and a new (to me) technical innovation!
First off, I was trying to come up with an elegant way to connect the linkages for the pitch control and rudder that would allow easy attachment and detachment for the WTC. I was strongly considering the tried and true brass clevises and threaded rods when I stumbled across my little collection of Dave Merriman's Clik-On connectors. They're great and use magnets to connect the linkages for small models. A great idea, but this model will be exponentially larger than what those were designed for.
The result was my own "home brew" Clik-Ons using rare earth magnets (six per set to be exact!). I created a rubber mold for the new parts, set in my brass tubing and then cast up the magnets in casting resin. The result is actually better than I'd hoped! The grip is truly remarkable!
I am also glad to report that all 21 of the LED lights are now completely wired in and working!
While I was working on that and waiting for the resin to cure, I took on painting the boat! I primed the model and then used a base coat of metallic bronze. It is actually quite bright, but I wanted to give a nod to the hero model which was made of bright brass. The lighter color also makes it infinitely easier to track while running at the pond!
After that, I mixed up a custom batch of weathered gray and brown to highlight all of the panel lines with. After that, I dusted the whole model with the same mixture to take out the brightness and offer a bit more of a weathered feel.
That done (and where I'm at as of right now) I used my pastels to add some streaking to the scupper areas.
Next on the list is to remove the masking tape and paint in the floodlight reflectors...
April 28, 2011
Batteries, bow thruster and prop!
I've painted in the floodlight receptacles with silver paint. This should help to get a more even light from the floodlight areas.
From there I moved onto revising my bow thruster linkages. Originally I used a piece of silicone tubing. I'd done that in the past with good results, but I didn't like the alignment in this case, so I pulled that section out and rebuilt it to allow the use of a dogbone connector. The dogbone will get rid of any alignment issues and make for a more reliable connections for the bow thruster.
During testing, I also discovered that my original propeller was off-balance and created a lot of vibration under full speed. I removed that propeller and drilled out another, paying more attention to alignment and cleaning up the edges. Hopefully this will get rid of the shaking that I was experiencing. I also tightened up the swiveling bearing in the tail, as there was about 1/32 of an inch of play that was contributing to the issue.
This morning I worked to get the batteries installed. They are twin 12V, 5Ah NiMh batteries. I'm going to run them wet and seal the ends with plastic dip or silicone. Hopefully that will keep them dry, as the rest of the batteries are well heat shrink wrapped and should be good for immersion in water. I plan to install the main power switch in the front of the boat for easy access to turn it on and off. I think I may also think about using a simple connector to turn the model on and off, which will also allow for charging.
May 3, 2011
I THINK that I'm ready for wet trials!
The batteries and lighting board have both been waterproofed with clear RTV. The batteries have had brass holddowns created, and the WTC has had a front holddown built and installed.
The salon bezel has had the floodlights and salon window fitted. The floodlights have been clearcoated with matte lacquer to help disperse the light better and hide the bulbs behind the lenses.
I've added what I estimate to be a good start to the flotation foam in the upper hull. Between the batteries and lead in the keel, the lower hull is quite heavy. The WTC itself should help considerably. I'm hoping the large distance between weight and flotation will create a really big moment of righting so the sub will stay upright even during high power acceleration.
Next up... test of WTC for leaks and trimming the boat!
May 9, 2011
Got the sub wet for the first time late last week! It went exceptionally well! The lower hull is nearly perfectly neutral in buoyancy between the weight in the keel and the flotation of the WTC. Once the upper hull was put in place, it floated nearly perfectly, high in the waterline with a slight upward pitch at the bow.
As luck would have it, the addition of a single lead ingot in the bow not only brought it to the correct level pitch, but lowered it slightly to a more correct waterline as well.
One of the things about the OTW module is that it is quite hard to get all of the water out of the ballast tank. There will always be a small amount in there, which will make the totally emerged waterline a bit lower than what is pictured below... nearly perfect!
I did find out that I need to reverse the pitch controller, as right now its backwards. That will take about a minute to do, just a simple matter of turning the pitch controller around.
The bow thruster worked very well. The rudder extension seems to halve the turning radius of the boat. The only way to know for sure how well it will work will be to get the model on open water. I hope to do that on the 14th after a business trip overseas.
October 17, 2011
Holy cow! Its been a long time since I've had the chance to play with this boat and get it completed!
Final trimming and testing of this model was completed yesterday in my pool. I'm very happy to say that it went off without a hitch and there were no glitches, hiccups, failures or leaks to report.
I'm also immensely happy at the performance that this boat has. Between the pump style ballast system from OTW and the bow thruster, this model is an absolute dream to control. Precise control over depth is always available, and she'll turn on her own length above or under the water. Be sure to check out the boring, technical video below, but more importantly the second part that has some great, high-definition video of her in action!