Moebius (Revell) Skipjack Build

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I like the smell of Dope. Good advice and I will heed your council. lol
A lot happened and I am not sure what I did was correct or the best way. If someone who has done this can share how they did this step, i would appreciate the knowledge.
I needed to know how much distance I have from the top of the cylinder to the upper hull. What I did was bend a wire that would go through the stand hole and line up with the cylinders that the top of the wire was flush with the top of the sub-driver. Also, where the wire exited out the bottom of the hull, I wrapped with painters tape (masking tape would work). Marked the point it exits with a pen. The top of the wire has a sharp point and when I pushed the wire up the tip would dig into the plastic and scratch. I also marked under the hull on the tape around the wire the point it now exits the hull. So when I pulled the hull apart. I measured the distance on the tape between lowered position and touching the top of the hull it was 3/8". The mark left on the plastic by the point was my reference point. With this I was able to see how far apart the top hull Klik-on was from my reference point I needed and an estimate of the offset.

A lot of measuring. The Klik-on needs to be raised 1/4", which is just about what my z bending pliers make it. As proud as I was about how it came out, there was a problem. That arch or brace I put in is in the way. I can dive, but surfacing will not happen because the rearward travel is blocked by that brace. Marked the area that will be cut away.

Slid the top hull on and peeking through the cracks checked the way it lined up. Tacked the pushrod with a little CA. Then quickly closed the hull up. I moved the sail planes until I felt the magnets meet. Set it aside to let the CA dry a bit. Opened it up and put more CA around the pushrod I made to the one coming out of the WTC. Closed the lid again and felt it connect again.

Another view.

[He Who Shall Not Be Named]

Put a piece of wax paper atop the SD, place a soft piece of clay on the wax paper, put a piece of wax paper atop the clay, and mash down the upper hull. Remove upper hull.

Wa-La! Annular distance established.

You a stick and paper type model plane builder, Tom?

M

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I did not even think of clay, brilliant. Thanks for the tip!

You a stick and paper type model plane builder, Tom?

M

Yes, I was. When I was about 10 or 11 started to build gliders and rubber band powered planes.

[He Who Shall Not Be Named]

Of course it's brilliant!

I was into free-flight big time, and competitive -- did four Nat's before joining the Navy. 1/2A gas, A-2 glider, hand-launch glider, jet-X, Unlimited rubber, Wakefield rubber, and scale. Every year Cathy Montz (spelling) kicked my ass in Unlimited rubber.

I too love the smell of dope and Ambroid glue. It runs in my veins.

M

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Ambroid glue.....loved that amber color.
I did gas airplanes, but they were the you-fly type, you fly around and around until you crashed or got crazy dizzy. Those tethered airplanes did not keep my interest long.

Back to business...... David, the air hoses, how do you run those? With the velcro strap going over the cylinder, I do not want them on top to be crushed. I could created some aluminum ducting, but the though of prying the hose off every time I open the cylinder seems problematic. Thoughts?

[He Who Shall Not Be Named]

Duh!

Leave the hoses ouside the Velcro.

You people!

M

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Yeah, what's the matter with you people? Sheesh. I was looking at your picture and I saw you had taped the tubing down,


it looked real tight. So I was not sure. Thank you. It is a duh moment when you think about it.

[trout]

Began to install the air hoses.

Then as I was attaching the hose to the aft end cap, it broke off.

[He Who Shall Not Be Named]

Hey, fumble-thumbs:

You'll find that you can't use the motor-bulkhead SAS manifold -- it sticks up too high and will hit the upper hull when you attempt to push it down in place. Don't use the manifold, rather run the flexible hoses straight to the induction and discharge nipples.

I'm enjoying this WIP, Tom. Good stuff.

M

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David that is encouraging that you like the WIP. It means a lot coming from you. A heads up earlier to not install it would have been better :-), but the information is out there for someone else not to mount the SAS manifold. I make mistakes and I post them (well mostly, I didn't post about the wind knocking my sail off the table and crud stuck to the sail or that periscope box was slightly too big because I assembled it with the fore and aft walls on the outside instead of the inside plus that latch - correctable, but would be a time consuming thing that I will fix later) Which is why I recommend waiting until she gets her maiden voyage before following what I did.
Taking the manifold off was not a big deal, it took a careful prying it away. I love RTV silicon, especially this blue stuff. I took some Acetone and carefully cleaned the surfaces and then picked, pull, scr@ped the rubber off.

Cleaned the sail pushrod off and realigned it (applied some CA, slid it on, then sealed the hull and moved the sail plane until it engaged. Let the CA solidify. Ran one hose (the other one will go on later after the pushrod connection dries completely).

Just cannot think my fat fingers pulling the hoses off these nipples will not eventually knock something else off. I might need to build a couple of connectors to make the process easier, but again the motto get it running first than add do-dads comes to mind.
I know this is a short posting. Life happens. That being said, I try to get one thing done on the sub each day.

[He Who Shall Not Be Named]

Yeah, I provide the motor-bulkhead manifold for those using this in the other 1/72 scale boats that are not as tight in the ass-end as the SKIPJACK. Sorry about that, Tom.

Can't wait to see this guy in the water.

David

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David, I am also getting excited about seeing her run. This is a great setup and if someone is reading this thinking can I build a sub, I will say a resounding yes! First sub or one of many this is a joy to build. We are getting close.
Finishing the hose connections.
The sail connection gets a strain relief. In this case it is a larger diameter plastic tube.

The air hose will be cleaned up at a later time. I have a connector I made, that I will need to test with a SAS system.


Next step is get some weight installed.

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The weights needed to be made.
Rolled out some potters clay. It was rehydrated, but a little too much. It was left for a day to ry out

Once it was in a useable condition, I measured and trimmed the clay to fit. As a whim, I carved a message and info into the clay.

Once dry, I put modeling clay in the base of a disposable plastic storage tub. Then stuck the clay pieces into the the modeling clay. I used plaster to fill the tub. I did not take pictures, but the process was once the plaster solidified, I dug out the modeling clay and soaked the plaster block in water. The potters clay will rehydrate and get soft again. Using a long toothpick or a bamboo skewer cleaned out the remaining clay.

I really rushed this last part. I put the plaster block in the oven on low for 4 hours (usually let it dry for a day or more). Melted some lead and poared in. Unfortunately the moisture cause steam and bubbling. There were no legible letters, but I had weights.

Tested the sub-driver in the tub. Everything stayed nice and dry. The only place that air bubbles showed up was from the side screw in the ballast tank. I will put a little RTV silicon in there.

This is SOOOO cool! Played with the SAS. I am going to like this system and can not wait to get the sub trimmed out.

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Tonight, I had to see what the Skipjack model looked like in the tub. Wow, the weight I made kept her in a upright position which is nice. There is nothing like the shock of putting a sub in the water and watch her unceremoniously flop on her side. I flooded the ballast tank and she settled aft heavy and bow would not go under. I grabbed some weight and placed it on the bow and the sub settled down to a level attitude. It may not stay that way once I get the sub in the kiddie pool because the tub may have been stopping the aft from sinking further.
Then I emptied the ballast tank and it was cool to hear the suction noise when the float dropped allowing the air to come in. I did not completely empty the tank because I had plenty of reserve. On the surface the aft was light. I am using a single battery, but if it is heavy submerged and light surfaced, so I see it will take a bit of playing to get it right.
Tried a little forward thrust while holding it......oh my goodness the power this puts out! Glad that it was dialed back to 50%, I might have lost my grip if it was 100% (pretty surprising the amount of power it generated).
I also played a little more with the SAS system, thank you Manfred! You were instrumental in the design of this and it worked wonderfully.
sorry about no pictures. It was just supposed to be a quick test and I got carried away playing. Possibly tomorrow!

[MFR1964]

Excellent Tom!, good to hear you like the SAS, it's the brainchild of a united effort on this forum, i only delivered my part to the system.
Can you make a vid from your SAS adventure?, wanna hear her woooosh.
As for connecting your SAS float, if i remembered right, you had designed a magnetic airconnector, i suppose you want to use this for easy handeling the SAS, great design!


Manfred.