USS Nautilus SSN-571 - 3D printed build

[billyd]

Shutter doors are normally opened individually.

One of the biggest (aesthetic) improvements for this otherwise, excellent 3D model is the inaccurate sail shape. If you can get the orignial sail STEP file and remove the angled leading edge of the sail, the change is is very noticable.

Thanks very much! I'll reach out and see if he will loan me the step file for the sail. That should be a relatively simple correction to make, good idea.

[billyd]

Been awhile but I have mostly completed the functioning shutter doors for the torpedoes. My goal was to allow for the potential to open each door individually, and also function in such a way as to not interfere with working torpedoes. I have achieved both goals.

Most of the time rc subs use a simple hinge method in order to have the doors fold inboard to open, rotating about their leading edge on a hinge. However I was unable to use this approach on my 1/72nd scale build as there was no way to make a hinge small enough and provide enough clearance for the torpedoes if they were fired. There simply isn't enough space at the leading edge.

So what I ended up doing was to have the shutters slide rearward along the inside of the outer hull to open. Each shutter is attached to a Gold-N-Cable and runs through integral tunnels I've added to hull section 2. By using Gold-N-Cable (2-56 size) and having them inserted (and glued) into the shudders at a specific angle, what happens is, as the cable is actuated forward the shutter will slide forward until it covers its window, and at that point the shutter will snap outward (flush with the outer hull) due to the spring tension naturally created in the cable (a combination of the angle and the bend as hull1 narrow towards the bow). When the cable is actuated backward to open the shutters, internal guides in the hull push the shutters inboard just enough to clear the rear most window edge and slide completely out of the way. No additional clearance around the shutters was required so the fit is nice and looks watertight.

I haven't drawn the Gold-N-Cable in the cad model yet so they are not shown in the pictures below. The supplied yellow plastic outer tube will slide into the newly added printed integral tubes in hull 2 and then the supplied brass cable runs inside them. This prevents the cable from rubbing on the rough printed plastic interlayers and instead runs through the smooth supplied gold plastic tube. The brass cable will get glued into the resin printed modified shutters and then an appropriate fitting is placed on the opposite end in order to connect with the driver of the modelers choice (servos or wtc actuators).

I had to make extensive modifications to the hull 1 piece in order for the shutters to function well in this manner. The existing attempt by the original 571 sub model designer was far too loose to work as is. Many changes were made to the shutters as well, in order to prevent all sorts of issues that would have occurred had the hull and shutters been left unchanged.

See some cad photos below. I have a working prototype (moving the cables by hand) and it works well. When I have it fully functional I will add more photos.

The integral printed tubes will not interfere with a torpedo firing system or my functioning retractable bow planes mod.

[billyd]

While waiting for electronics to complete the operational torpedo shutters prototype I am working on correcting the 3d model of the sail of the 571 to be more scale in appearance. Specifically the forward angle (and also a slight adjustment to the rear as well). I am working off of photos of the real sub I found through a simple search online. The tricky part is the sail appears to have gone through a few changes so it's hard to tell if the existing model has other details wrong or not. The designer of the 3d printed model was kind enough to supply me with his original sail model in an iges file, so making the changes is quite a bit easier (although still surprisingly tricky). If anyone can point me to the best pictures to follow as I travel down this rabbit hole it would be greatly appreciated. Hopefully the existing sail is mostly correct other than the angles I mentioned. Thanks in advance.

[billyd]

I decided for the prototype to use two waterproof linear actuators. Each would operate three shutters, one for port and one for starboard. I should have this built in about a week.

I also made really good progress on the modified tower (sail). Just have a little more to do and that will be done. The sail apparently changed 3 or 4 times over the 571's lifetime. I have settled on how it looked when it first was built. (as best as I can tell as information is scarce and I had to do a lot of guessing.) Going to add navigation lights to it (functional) and I am waiting on parts to get measurements to make sure the model is correct in this regard. Edit: And I changed the location of the flag from the original 3d model as it wasn't correct (he had it located on top of the sail towards the stern). The flag was actually located on the stern side of the sail but just several feet off of the deck. The real sub looks like it may have been tied off to the starboard hand rail, but for simplicity and symmetry I placed a flag shaft mount on the centerline of the stern side of the sail. Not exactly correct but I think a good compromise.

[Das Boot]

On November 10, 1966 the USS Nautilus (SSN-571), while running submerged, collided with the USS Essex (CV-9) 350 miles off the coast of North Carolina. They were conducting an underwater replensihment exercise. Both ships needed exstensive repairs. This was one instance the sail changed and I believe the last.

[billyd]

On November 10, 1966 the USS Nautilus (SSN-571), while running submerged, collided with the USS Essex (CV-9) 350 miles off the coast of North Carolina. They were conducting an underwater replensihment exercise. Both ships needed exstensive repairs. This was one instance the sail changed and I believe the last.

Thank you, yes I spotted that amongst the photos and web pages I searched. The sub also went from recon to a stealth warship as the cold war progressed, thus the change in color scheme to all black, and the removal of navigation lights and also the rectangular "windows" on the sail were replaced with what appears to be scuppers fore and aft. It also seems like they changed the location and number of masts. I think it started out with 7 or 8 of them, and then increased but it's hard to say exactly how many more because I can't find photos with them all extended. It doesn't matter as I am doing the stock 571 (as best as I can tell I am sure I have some things wrong).

[CC Clarke]

Good sail leading edge conversion!

The beavertail exhaust plate is far too thick as originally modeled.

This is what I ended up with. The Type 2 and 8 periscopes, including snorkel have been replaced, with whips added to the sides, along with a cutout for the sail light on the aft edge.

[billyd]

Prototype for operational torpedo shutters is completed and works well. You can operate either side or all at once.

[billyd]

Here's a view of the mechanics operating.

[Das Boot]

Any updates?

[Das Boot]

What kind of printer did you use, and can this be printed in 1/96?

[billyd]

Sorry been awhile, I've been struggling to get the shutters operating on one linkage. It's very difficult to get the load to acceptable levels when sliding all 6 shutters at the same time through gold-n-cable. I do believe I have a good working solution now, but between the holidays and other life crap it's been a long time. I've attached a rendering of the final design. When I have the package complete, Bob will offer the design on his site. This is really the companion to the functional bow planes that he already lists, but I believe they will be offered as a package, since it really is setup to do both. I also finished up the sail mod, and will probably include that in the same package. There are a lot of options when it comes to the sail and the 571, but I have settled on how it was when it first left the shipyards. I will not claim that it is perfectly scale, as I made a few compromises between practicality and perfect scale. Also I had to make a lot of educated guesses that I hope are not too stupid lol. I have added navigation lights along with a forward search light which will all be functional, but they are probably too big and more pronounced than the real sub (this is due to the size of leds used and their clear cover. I did not add the whips I figure those could be added on separately.

[billyd]

What kind of printer did you use, and can this be printed in 1/96?

Sorry been awhile. Scaling the boat would be no problem, but as far as the mechanical designs for the 571 I've done, scaling it down would be very difficult. Even at the current 1/72 scale some of the components are very small and would be quite difficult to print any smaller. Also any hardware used would also have to be scaled accordingly and really complicate things. Scaling it larger is more feasible but still comes with it's own set of complications. Really I would have to design it from the ground up to change the scale of it, or the person doing the build would have to.

As far as my printers I have a vcore3.1-500 with 4 color capability, a vcore3.1-200 which is my speed machine, prints at 300mm/s but I usually do 200mm/s for the best quality. My resin printer is an Elegoo Saturn 4 Ultra which is really awesome. I have ordered a vcore4-300 IDEX machine for really complex prints using different materials. I will probably outfit it down the road to do the more difficult materials life the CF impregnated materials, nylon and polycarbonate but for now it will be stock.

[biggsgolf]

What kind of printer did you use, and can this be printed in 1/96?

I am currently printing it at 80%, found that to be the minimum size without issues.

[billyd]

I am currently printing it at 80%, found that to be the minimum size without issues.

I would imagine the boat starts getting really tough to print at smaller scales. I found myself occasionally wishing I had done a larger scale as I got into the project. But I am married to it now.