Building a 3D printed RC submarine. The French Redoutable.

[RCjetdude]

I bought the files from Bob Martin at the Nautilus Dry Docks for his 3D printed 1:96 French Redoutable RC submarine and am currently printing the parts. When done it will measure out around 53" long which is a decent sized sub. I am printing it out of PLA+ and am on my second spool of filament. This sub is the third one he has created files for and he has plans to do more. The walls are nice and thick and it prints easy with no need for rafts and few if any supports. Here are a few early shots of some of the parts taken from the print bed and taped together without any clean up.









More to follow....

[RCjetdude]

Printing hull section 7 now. It's bigger than I thought. Ordered the hardware and water tight cylinder for it. Making good progress. I will print everything before I start to glue it together. I did start sanding the parts and have some filler on the way although I don't think it would take much more than coats of primer and wet sanding to smooth it out.

[RCjetdude]

All the printing is complete and I have glued together the main components. I still need to install the middle and rear bulkheads and do some more sanding and filling work but the seam looks tight. Some of the files did not slice well using Simplify 3D but it worked out. It has taken just over two spools of filament to complete.

[Alpha]

That is a good looking sub! Get out the bondo and sanding blocks! How are you finding the PLA+ filament for a project this size? What wall thickness is the outer hull?

[RCjetdude]

The PLA+ has worked fine. It behaves much like PLA when printing but with a higher nozzle temp. I am running mine at 230C. I have yet to see just how it holds up but the wall thickness of the hull is about 3mm. Very stout. Bob recommends fusing the joints of the hull sections with a blunt tip soldering iron as an added precaution because the hull is fairly long. The bulkheads are also intended to be glued in place on the joints which adds even more strength. I did run into a few minor issues with the files and how the parts printed but a few settings changes and it was nothing insurmountable.

[RCjetdude]

I have completed installation of the bulkheads and the 6-32 stainless steel screw and nut used to secure the back of the hatch. The bulkheads are designed to hold a 3" or equivalent sub driver. I will be using a new modular sub driver just like what Bob Martin used to outfit his prototype. 3/16" brass pins are used to align the top and bottom bulkheads.

[RCjetdude]

I added some 0.10" styrene to the tail fins to help strengthen where the 1/16" hinge rod goes. I felt it was just too thin as printed.



The bow is attached to the front of the upper hull and locks onto this foremost bulkhead while the back is secured with just one screw into the rear bulkhead.







Starting at the bow and moving aft filling any of the really low places with Evercoat Rage filler.



Primer and wet sanding will fill the rest.

[RCjetdude]

First coat of black primer. All the fill work has given me a really good foundation to work from. When finished I doubt it will even be possible to tell it was 3D printed.

[Alpha]

Wow, you work quicklyl ! Looking good! I assume you're using enamel primer on this one?

I'm usually an Akula or Type VII guy but this Redoubtable's lines are really growing on me. Everything looks better in black!

[RCjetdude]

Just Rust-Oleum. I know what you mean. Initially I wasn't to keen on it but it has grown on me too and is actually a good looking boat. Someone else has designed a 1:48 3D printable German type XXI that is available on the Nautilus Dry Docks but it comes with brass photo etched decking and decals. 63" long when done and very detailed but very pricey compared to the Redoutable.

[RCjetdude]

Ready for the sub driver.

[RCjetdude]

[RCjetdude]

Test fitting the sub-driver. It is a modular sub-driver from The Nautilus Drydocks. It fits perfectly and is a kit specifically for the Redoutable. I need to provide servos and of course the receiver and a few pieces of brass rod and tubing but the kit comes with pretty much everything else. The sub-driver is an amazing piece of equipment. It even comes with a nice brass 7 blade scimitar propeller.

[RCjetdude]

The sub driver is comprised of a forward battery compartment which also contains the fair water planes servo, a central ballast chamber and a rear control compartment which houses the radio equipment. The forward and aft compartments are connected via an internal brass tube and remain dry. The sub driver required micro servos and a slight modification to the receiver tray for my rather large receiver to fit. There is a lot of stuff inside one of these. The sub driver is actually quite a well designed and built piece if equipment. It comes with a ballast servo and pump installed. I added an optional emergency ballast system which is the copper cylinder located inside the ballast chamber. The ballast servo pushes on a lever which opens and closes a vent in the top of the chamber. The same lever depresses a Schrader stem to blow the emergency ballast if needed. Badger propel is used to charge the EB cylinder. The ballast servo also engages a micro switch to activate the air pump which pushes the water out of the ballast tank allowing the sub to surface. The basic operation is as follows: vent open, ballast chamber floods and the sub submerges; vent closed, sub maintains desired buoyancy; vent closed pump on, air is drawn from the dry chambers by the pump and the sub begins to surface. A snorkel assembly located in the sail opens when the sub breaks the surface allowing fresh air to be drawn in by the pump and equalizes the dry chambers thus completing the blow process. The emergency blow is tied to the fail safe function of the radio such that if a signal loss occurs the ballast servo engages a Schrader stem and pressurizes the ballast chamber. Pretty slick actually. A key fobb device is used to power up the sub externally which is cool and there is a gyro like device called an AD2 which helps stabilize the aft dive planes. A BLM or Battery Link Monitor indicates the state of capacity on the battery and monitors the radio signal in order to engage the ballast servo if needed. Currently l am working through an issue with the fail safe on my radio and how it interacts with the BLM. The control surface pushrods are connected via powerful magnets and a slide in dog bone assembly making the entire sub driver easily removable. I designed and 3D printed several parts to connect the aft control linkages and mount the fair water planes servo. This has been a huge learning experience for sure and I am almost ready to begin the process of trimming the boat. Adhesive backed lead strips will go in the bottom and strips of foam in the top until a slightly positive neutral buoyancy is achieved.

[Alpha]

This is looking really good, Steve, you're almost ready to trim it in the water!

[RCjetdude]

Added a scum line and some weathering.

[GBLynden]

Great work man!

[RCjetdude]

Thank you sir. If I can sort out the pitch controller it would be ready for sea trials. Might have to do with my receiver. Working on the process of elimination to try and determine what is going on there.

[GBLynden]

Get video when you do the maiden!

[Peterboi]

Wow thats awsome well done..👍