Moebius Skipjack

[Ken_NJ]

Yea you can do that as well. I like my method. Probably others ways.

[Subculture]

Something you can do is squirt a little silicone RTV in at each end of the heat shrink of each device, which effectively pots the boards, and protects them well against any unwanted water ingress but it can be removed readily enough if the device requires servicing.

[Ken_NJ]

I think it's been about two years since I 'finished' the Skipjack. And I'm still working on it and getting it to be 'perfect'. David helped me by replacing a cracked cylinder and the safety float valve. Now so far no water intrusion. Over the winter I will be improving the trim so I'm ready for Groton in 24.

The following should not need to be done but I did anyway in order to protect the BLM and AD2 since they are in a vulnerable spot being under push rod penetrations in the bulkhead.

I save the smooth sections of the acetate containers that spinach comes it. I has been useful for cutting tape when I made masks for the Skipjack. You can cut the tape with scoring thru the acetate. It takes quite a bit of pressure to cut thru it. I try to remove the sticky labels so I have a complete clear sheet. Goo Gone works.





To protect the BLM and AD2 I cut a section to approximate size. I scored the acetate with 1-2 passes of the blade which allowed bends to be created. Those bends are strong, unlike what styrene would do. I also created tabs that folded around so corners can be glued with CA creating a sturdy box.





Once it was glued, and a little more trimming, it fits nicely in position to protect the electronics from any possible drips. And it's clear so you can still see the status LED's.



A for 'what it's worth'. Probably has other uses as well.

[Ken_NJ]

Thank you Steve and Tom. Your comments are most appreciative! We all have our level of skill and detailness we will go to. Steve, your large scale subs are works of art. Not something I would tackle.

For my connections between different model sections I use these waterproof connections in the first pic. I have five pairs of these to attend to. I use 2, 3 and 4 pin versions.



For the beacon LED to Beetle connection I use some PCB connections I strip from things that are getting thrown out. They are of course not waterproof so before each mission I dab Corrosion-X on it.



For the deck LED, I use this guy and do the same with Corrosion-X. If it comes down to it after time, they can get replaced.



Any exposed to water soldered connections, I smother with silicon then heat shrink it, then finger dab silicone on the ends of the heat shrink to make sure it is sealed.

That should answer more than what you asked Tom. For the benefit of all I guess.

[trout]

Ken,
You really are inspiring. Love your creative thinking and the cleanliness of your installs.
How are you sealing your connections to the deck LED and beacon?

[SubDude]

This is awesome stuff Ken. The presentation is right up there with the illustrious Mr. Meriman. I have two of these kits to build (the ones I got at Subfest last year) but I can assure you that I will not go quite so detailed as you have. I humbly submit to your praiseworthy skills.

[Ken_NJ]

Finally for today, inside of my sail.









Today's post starts at #307 so you should scroll up and start there if you want.
Or click this... https://forum.rc-sub.com/forum/build...310#post162310

[Ken_NJ]

For the blinking submarine beacon I think I previously posted how I encase two micro LED's in epoxy. This beacon manually telescopes from the sail. To make it blink, I used two digital outputs from a Bluno Beetle. More can be found at Nicks Blinky thing thread here, https://forum.rc-sub.com/forum/gener...a-blinky-thing
Ed posted his code there, which I modified for two LED's. I used two resistors, one for each LED, soldered and shrink wrapped to the two digital outputs on the Beetle board. I made an acrylic box with lid and sealed the Beetle board in the box using silicone as a sealant. The box was placed inverted in the hull, if there was a leak, an air bubble should keep most of the water from the board.



A 7805 provides the required 5 volts to the board.


Here you can see the package taped inverted to the inside hull, the 5 volt regulator and the connector. As part of the pre-mission procedure, I brush some Corrosion-X on the connectors.



This is my code for the Beetle. With notes as I won't remember what I did.

//Programming date May 2022
//Connect Beetle to right side, forwardmost port
int ledD2=2; //Digital pin D2
int ledD3=3; //Digital pin D3
//Bluno Beetle pin reference
// D2-D5 = Programming Reference 2-5
// A0-A3 = Programming Reference A0-A3
//Operating voltage 11.1v (3s Lipo)
//7805 Voltage regulator for Beetle input voltage
//100 ohm resistor for each LED
void setup() {
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
}
void loop() {
digitalWrite(ledD2, HIGH);
digitalWrite(ledD3, HIGH);
delay(600);
digitalWrite(ledD2, LOW);
digitalWrite(ledD3, LOW);
delay(600);
digitalWrite(ledD2, HIGH);
digitalWrite(ledD3, HIGH);
delay(600);
digitalWrite(ledD2, LOW);
digitalWrite(ledD3, LOW);
delay(600);
digitalWrite(ledD2, HIGH);
digitalWrite(ledD3, HIGH);
delay(600);
digitalWrite(ledD2, LOW);
digitalWrite(ledD3, LOW);
delay(3000);
}

[Ken_NJ]

I wanted a third magnet at the aft end to hold the sail top on securely. My first attempt I tried to glue both magnets simultaneously. Well they came out crooked. Note to self... don't try to blindly glue two parts at the same time. They would work fine this way, but me being anal about things I removed it, then epoxied (G-flex) one of them in place. Next day epoxied the other one in place using the first one to locate the second one. I then applied a fillet along the edges of the magnets for additional holding power. The glued side of the magnets were run on like 180 grit sandpaper and the styrene surface was roughed up as well.



Much better.





To activate the navigation lights I made my own periscope. The bottom is a tube and at the bottom of the tuber is 1/2x1/16 magnet, epoxied in place.


When I insert the scope it activates a reed switch which then turns on the nav lights. Essentially and on-off switch.
Under the rectangular foam is another reed switch. The foam is attached to a float with a magnet. When the boat is surfaced, the nav lights are on. When submerged, the float rises, deactivating the nav lights.
Also when the boat submerges, the same reed switch activates a safety location LED on the deck to help locate the model should it not rise to the surface.



Hand made micro periscope from brass.



Sub beacon and periscope.

[Ken_NJ]

Now for the lower gear. I made another set of bearings\spacers. These do two things. They cut down on friction between plastic and brass, although the plastic gear is already loose fit on the shaft. And they center the gear on the shaft to align it with the upper gear. I made the proper length spacers. The existing plastic 'bearing' was also hand reamed to the proper size and was CA'd in place as before.



Due to all the friction, this gear bent and magnet hole elongated. This had to be fixed.




I made two brass sheets. One had a extension for a ball joint. The surfaces were roughed up, then epoxied and clamped. No more bend. I added two 1-72 machine screws just in case the epoxy gave way.







Test fit of both gears.



The magnet is gone and replaced with a ball and socket joint. Much more reliable connection. AND, after all this work, the servo to fairwaters connection works excellently! A lot less friction.

[Ken_NJ]

Also prior to Groton, the fairwaters had enough friction that the magnet from the servo would not hold on or move the planes, kept becoming separated. I made a small 1/16-3/32 long bearing from brass. Where the fairwaters shaft entered the sail on the inside, I use the correct size drill and hand reamed out that hole to fit this bearing. I did not go all the way thru, so the outside of the sail you do not see this bearing.



I then cut a spacer and carefully filed it down so it can be used to hold pressure against the bearings while they are being glued.



With the bearings in place, the spacer in place, the sail halves together, an alignment rod lined everything up. A few drops of CA was applied thru the bottom of the sail with a pointy thing onto the bearings on the inside of the sail to hold them in place. The sail was taken apart then a fillet of CA was added around the bearings.



The fillet of CA was then filed down to make the CA smoother. The fairwater gear as is fits exactly between the sail halves. I had to ream out the gear opening down to the set screw to accommodate the bearing. I also had to ream out a camfer so there was no binding with the CA fillet.



The new fairwater planes needed the forward part filed down so it did not interfere with the sail when at full dive or full surface.



Not shown, I also ground some flats where the set screws touch the shafts.

[Ken_NJ]

Prior to going to Groton I lost one of my fairwater planes. David did not have any spares and Bob is not at that point of making resin parts. I took the original Moebius parts from the kit and prepped them. Made a shaft and put notches in it for epoxy, filled the voided space on both halves and clamped together. Next day sanded. You'll see them painted up in a later post. They feel solid, no hollow sound at all when tapping on them.

On of the original resin planes, part of the fittings kit.


Prepping Moebius parts.

[He Who Shall Not Be Named]

Ken
Thanks for the information on the magnets and epoxy, ordered them and they just arrived this week. Those are some strong magnets for being so small.

When you completed your final trim what was your new trim weight and foam configuration? My friend is opening her pool up this week, I’m going to attempt trimming mine tomorrow.

I had the same problem (no stern plane control) while running my Blueback at Groton in 2019. The grit was between the fixed portion of the stern planes and the moveable plane. I tried sanding between the back on the stern planes and fixed portion but I wasn’t able to get enough clearance between the two to get in working correctly. After Groton I ran it my friend’s pool and had no problems with it.

Thanks
Ernie

Of all the places I've operated, it's Groton that presents this unique problem. It's owing to the very gentil slope at the launching/retrieving point. The heavier model will be more prone to scooping up sand as it slides in and out of the water. Most other sites either have a hard bottom or sand with a steep incline. The best course of action is to shake the immersed model back and forth to dislodge any sand that gets between the stern plane leading edges and trailing edge of the horizontal stabilizers. Or, provide a wider gap between the two.

[SSN687]

Ken
Thanks for the information on the magnets and epoxy, ordered them and they just arrived this week. Those are some strong magnets for being so small.

When you completed your final trim what was your new trim weight and foam configuration? My friend is opening her pool up this week, I’m going to attempt trimming mine tomorrow.

I had the same problem (no stern plane control) while running my Blueback at Groton in 2019. The grit was between the fixed portion of the stern planes and the moveable plane. I tried sanding between the back on the stern planes and fixed portion but I wasn’t able to get enough clearance between the two to get in working correctly. After Groton I ran it my friend’s pool and had no problems with it.

Thanks
Ernie

[Ken_NJ]

Thanks Bill. I thought that something like that would be the case.