Revell Gato 1/72 - Newbie no more Part duex

[He Who Shall Not Be Named]

First off, it's not a bearing it's a 1/16" pushrod seal. Second, the bubbles (good methodology finding the leak, by the way): are they originating around the seal body, or around the 1/16" pushrod itself?

Re-test with an eye to finding where the leak is. Is the leak around the union where the seal body mates with the motor bulkhead, or is the leak originating at the encapsulated O-ring that seats around the brass pushrod?

If the leak is around the seal body then the fix is easy: Put some RTV around the seal-motor bulkhead union and push it in with a finger as you take a suction on that hose. The partial vacuum you create within the SD will pull the RTV into the openings between seal and motor bulkhead that previously leaked air during your test.

If the leak is at the seals O-ring. You're screwed. Throw everything in the trash and take up knitting. Hell .... I got your money. It's over. Let that be a lesson to you! ...

... Naw, just kidding. Here's how to replace the pushrod seal:

The RTV securing the seal within the hole it fits within (the motor bulkhead) is relatively weak. You don't even have to take the pushrod out (in fact, I wish you wouldn't). Pull the motor bulkhead out of the cylinder enough to push an 1/8" metal rod onto the forward face of the offending seal, and push it aft. The bad seal will pop out of the motor bulkhead with little drama. You previously removed the magnetic coupler so you can slide the bum seal off the after end of the pushrod.

Take your replacement pushrod sea; slide it onto the after end of the pushrod; and, before you push it into its hole, run a bead of RTV around its base -- taking care not to get any of the goo onto the forward face -- we don't want RTV to come into contact with the pushrod!

Push the replacement seal into position and let things cure out a few hours. Re-test for watertight integrity.

You need parts, give me a jingle and I'll get them out Monday.

Onward!

David

[trout]

David,
I stand corrected....actually I have no idea why I have called it a bearing. LOL, As far as taking up knitting? I have come to far to let a little seal stop me now. The leak is from the o-ring. It was hard to tell at first whether it was the pushrod seal or the SNORT tube (they are so close together). Until I was able to control my breath to slow it down to one bubble as needed. That is when I could see where exactly it was coming from. The good part about this is I am learning something new! and I am one step closer to trimming her up.
You like my technique? I learned that from some guy named David Merriman, heard of him?

Side note, How much of the conning tower and do-dads do you put on. What I mean is, should I have all the deck (guns, railing, etc) and tower completed (not detailed) for trimming or the small difference can be adjusted later?

Also, what is in the conning tower inside where the open doors are?

sorry the picture is blurry, but I wanted to quickly post this.

[Reckless]

if I remember correctly (and I'm sure someone will correct me with a rolled newspaper if I am wrong) .. theres nothing in there, except access to the top of the conning tower and the main hatch down into the sub.

the "doors" you see on kits was added after the war to lock the sub up while it was displayed to the public... as the kits were modeled after I don't remember which sub (sorry! I should know this .. LOL) is on a full land display

[trout]

Reckless,
Thank you. The model is based off of the USS Cobia

You can see the broom that is on top, just like the model.
Peace,
Tom

[Reckless]

sonar sweep? ...

[He Who Shall Not Be Named]

You step through that opening and you have, to the left, a huge concave circular 'dish'. That's the after end of the conning tower proper (cylindrical, pressure proof structure where the boat is conned while submerged). To the left are the forward ends of those long gun/ammo storage lockers you see projecting out the after end of the fairing. Above, a lot of truss work under the cigarette deck -- re-enforcing members to harden the gun platform. In the center of the fairing, to the right of the door, is the big main-induction valve (kinda looks like the upper end of a dance-club 'smoke eater'). And within the superstructure fairing itself you'll will see stringers and frames. Very busy looking in there. And smelly.

David

[trout]

sonar sweep? ...

LOL, no clean sweep - successful mission
I have read that it is originally from Dutch Admiral Maarten Tromp, who legend held, placed a broom at the masthead to show he had swept the sea clean of the foe--the English in his case. There is an old song called "The Admiral's Broom."

Dave any pictures in your archives? Mark you got anything??

I again want to thank everyone for all your help.....It is getting close to trimming time and I can feel the excitement building. For all that are taking on the Revell Gato keep plugging at it! It is worth the challenges!

[He Who Shall Not Be Named]

David,
I stand corrected....actually I have no idea why I have called it a bearing. LOL, As far as taking up knitting? I have come to far to let a little seal stop me now. The leak is from the o-ring. It was hard to tell at first whether it was the pushrod seal or the SNORT tube (they are so close together). Until I was able to control my breath to slow it down to one bubble as needed. That is when I could see where exactly it was coming from. The good part about this is I am learning something new! and I am one step closer to trimming her up.
You like my technique? I learned that from some guy named David Merriman, heard of him?

Side note, How much of the conning tower and do-dads do you put on. What I mean is, should I have all the deck (guns, railing, etc) and tower completed (not detailed) for trimming or the small difference can be adjusted later?

Also, what is in the conning tower inside where the open doors are?
[ATTACH=CONFIG]12288[/ATTACH]
sorry the picture is blurry, but I wanted to quickly post this.

For your initial sea trials -- where you will establish submerged trim, surfaced trim, work out the many bugs that reveal themselves only after all the sub-assemblies have been integrated into the whole -- you'll put it in the water with only the basic hull, control surfaces, running gear, retract mechanism, and sail assembled and working. That's it.

No stanchions, capstans, railings, cleats, no guns, no antenna, no deck fittings. Nothings installed that's going to get knocked off by your fat inexperienced fingers. During sea trials (and you will be tried!) you will be handling that model a great deal: lifting the deck and putting it back down, again, and again, and again ..... You will be tweaking the linkages, adjusting the blow/vent settings, moving weight and foam around. AND learning how to drive this beast.

All this activity puts the physical condition of your pretty model submarine at great risk. Don't even paint it till your done with sea trials.

Make it pretty only after you got it running reliably, you master how to drive the thing, and you naturally stop calling your model submarine a screaming *****, and instead start addressing it as, 'she'. At that point, you put all the do-dad's on and give it, ah ... 'her', a proper paint job.

David,

[Reckless]

For your initial sea trials -- where you will establish submerged trim, surfaced trim, work out the many bugs that reveal themselves only after all the sub-assemblies have been integrated into the whole -- you'll put it in the water with only the basic hull, control surfaces, running gear, retract mechanism, and sail assembled and working. That's it.

No stanchions, capstans, railings, cleats, no guns, no antenna, no deck fittings. Nothings installed that's going to get knocked off by your fat inexperienced fingers. During sea trials (and you will be tried!) you will be handling that model a great deal: lifting the deck and putting it back down, again, and again, and again ..... You will be tweaking the linkages, adjusting the blow/vent settings, moving weight and foam around. AND learning how to drive this beast.

All this activity puts the physical condition of your pretty model submarine at great risk. Don't even paint it till your done with sea trials.

Make it pretty only after you got it running reliably, you master how to drive the thing, and you naturally stop calling your model submarine a screaming *****, and instead start addressing it as, 'she'. At that point, you put all the do-dad's on and give it, ah ... 'her', a proper paint job.

David,

... awwwwwwww... does this mean mines never gonna work cause I got it with all that stuff already on it? :(

[vital.spark]

The answer from experiance is JUST BE CAREFULL!! think and look where you put your hands and what can you bump with the model when moving it! And the answer is, you will shortly become an expert at reattaching broken off bitts and pieces!!

[He Who Shall Not Be Named]

... awwwwwwww... does this mean mines never gonna work cause I got it with all that stuff already on it? :(

You're screwed!

[trout]

The RTV securing the seal within the hole it fits within (the motor bulkhead) is relatively weak. You don't even have to take the pushrod out (in fact, I wish you wouldn't). Pull the motor bulkhead out of the cylinder enough to push an 1/8" metal rod onto the forward face of the offending seal, and push it aft. The bad seal will pop out of the motor bulkhead with little drama. You previously removed the magnetic coupler so you can slide the bum seal off the after end of the pushrod.

Take your replacement pushrod sea; slide it onto the after end of the pushrod; and, before you push it into its hole, run a bead of RTV around its base -- taking care not to get any of the goo onto the forward face -- we don't want RTV to come into contact with the pushrod!

Push the replacement seal into position and let things cure out a few hours. Re-test for watertight integrity.

You need parts, give me a jingle and I'll get them out Monday.

Onward!

David

Thank you David for the seals.
The replacement of the leaky seal goes as simple as David says.
I pushed the pushrod seal out - surprisingly simple.
I could not slide my old seal off the pushrod because I had a soldered end, but once it was out it was a simple matter to loosen the end off and re-solder it back on

Placed the RTV on the seal outer edge and slipped it into place. Gave it a few hours to set and did the water test. I had to blow a lot harder, but I had bubbles.....dun dun dunnnnnn (for that dramatic touch). The good news is it came from the seals edge (near a bubble in the casting )

and near the motor shaft also from a subsurface bubble.



So for the seal I placed some additional RTV

and same for the Motor shaft area

Once the RTV was placed on the areas I created a negative pressure in the WTC to suck in some of the RTV into the leaks. Let this dry.
My son and I both tested the WTC - NO LEAKS!


Now I will replace the one that is so tight.

[trout]

Today was going to be a day to spend on the sub. I was adjusting the servos and made the decision to wait until after working on the ballast to replace the other pushrod seal. As I was testing the rudder throw when all of a sudden all the servos shuddered like it was cold, then the bow retract servo went bezerk throwing its arm all the way in one direction then the next, finally seizing and jittering. All servos became unresponsive. The ADR-2 did not have any lights on it and the LiPo Guard was blinking green. It looked like radio signal was lost. Looked at the battery on the transmitter it was low, but not crazy low. I restarted everything and no luck on servos response. I went ahead and decided to recharge the batteries. The TX batteries were on the charger and then I put the LiPo on. It would not charge.......it has died!
Mike, you will get a call from me on Friday (payday) for a new battery.
sigh......

[He Who Shall Not Be Named]

Maybe you fried the ESC's BEC?

David,

[trout]

How? And please tell me how do you prevent that? I guess I won't know until I apply a new power source.