My first build, and I need help!

[beeryboats]

I've started the GATO build with Davids sub driver and DVDs. I'm hung up on the aft section build so I sent David an email. He advised I share my stupidity with the group. I've been building RC aircraft for decades and know that there is a point on some builds you better have all your control rods in place before you cover everything up. I'm trying to figure out how just gluing the skeg on with rtv does you any good as you will never be able to get to the control links in the hull. Unless you gain access through the stern tube holes? I swear I saw David glue the lower rudder bearing in place, so I did the same. But even if the lower bearing was loose, you could never get to the bell-crank above it... Can anyone explain the secret to me?

Thanks,
Jay

[He Who Shall Not Be Named]

Jay,

I make the rudder operating shaft (1/16" brass rod) removable from the rudder. The operating shaft is held to the rudder with a 4-40 set screw set into one side of the rudder -- this set-screw holds the shaft fast, or when loosened, permits you to pull the operating down enough so you can slip the cast white-metal bell-crank on or off (working through one of the torpedo tube openings back there.

Instead of RTV, use two 2-58 flat-head machine screws to hold the lower half of the stern plane operating shaft bearing piece in place -- this will permit you to remove/install the stern planes to the skeg.

David

[beeryboats]

Do you make the dive plane bell-crank hole in the hull large enough for the clevis to come down throught the hull? That would be the only way I can think of to make it removable.
Jay

Jay,

I make the rudder operating shaft (1/16" brass rod) removable from the rudder. The operating shaft is held to the rudder with a 4-40 set screw set into one side of the rudder -- this set-screw holds the shaft fast, or when loosened, permits you to pull the operating down enough so you can slip the cast white-metal bell-crank on or off (working through one of the torpedo tube openings back there.

Instead of RTV, use two 2-58 flat-head machine screws to hold the lower half of the stern plane operating shaft bearing piece in place -- this will permit you to remove/install the stern planes to the skeg.

David

[He Who Shall Not Be Named]

Do you make the dive plane bell-crank hole in the hull large enough for the clevis to come down throught the hull? That would be the only way I can think of to make it removable.
Jay

No, Jay.

What's wrong with you people!!!.....

I send you to school, buy you books, and what do you do?! You eat the Teacher!

First, attach the white-metal bell crank to the pushrod and place a drop of CA to stiffen the two (later working of the two breaks the bond and free's the bell-crank to swing with motion of the pushrod). To install the bell-crank to the rudder operating shaft you lower the rudder shaft down so its top is about center in the hull. You then position the bell crank over it and slide it down, using the pushrod as a handle. This way you don't have to get your fat fingers in the tight confines of the stern.

After pushing the rudder operating shaft up into its upper bearing, center the bell-crank in the middle of the hull, then tighten its set screw by inserting the Allen wrench through one of the stern tube openings.

David,

[beeryboats]

dive planes, dave. Not the rudder. I dun figgered that 1 out! How do you install the dive plane clevis to the bell-crank on the dive planes once the aft hull is glued to gether? Do I have to call the wife's OB/GYN to get in there and hook it all up? They have very special tools ya'know.....
Jay

No, Jay.

What's wrong with you people!!!.....

I send you to school, buy you books, and what do you do?! You eat the Teacher!

First, attach the white-metal bell crank to the pushrod and place a drop of CA to stiffen the two (later working of the two breaks the bond and free's the bell-crank to swing with motion of the pushrod). To install the bell-crank to the rudder operating shaft you lower the rudder shaft down so its top is about center in the hull. You then position the bell crank over it and slide it down, using the pushrod as a handle. This way you don't have to get your fat fingers in the tight confines of the stern.

After pushing the rudder operating shaft up into its upper bearing, center the bell-crank in the middle of the hull, then tighten its set screw by inserting the Allen wrench through one of the stern tube openings.

David,

[He Who Shall Not Be Named]

You DID say dive planes. I was thinking rudder.

I'm an idiot!

Before slipping the dive plane assembly onto the skeg you install the pushrod to the hole atop the dive plane operating shaft bell-crank (soldered to the operating shaft). You insert the after end of the pushrod into the opening within the skeg and work it forward till the operating shaft sits in the half-cylinder bearing surface of the skeg. The bottom half of the operating shaft bearing is secured with two 2-56 flat-head machine screws.

Sorry about the confusion, Jay.

David

[beeryboats]

Ok! That's what I thought. I reviewed the video and on your build, the hole between the bearing surfaces in the hull is a little larger than on my sub. I was afraid of removing too much plastic. I'll open that up a bit and glue the aft hull together. Next comes the prop shafts!

Jay

[beeryboats]

ARRGG! The prop shafts just about drove me crazy. Twice I glued the shafts in the after supports. Thankfully my wife had some nail polish remover to get them undone. I should have oiled the shafts so the CA wouldn't stick to them. One is slightly tighter than I want it to be so I may try some valve lapping compound and a low speed drill to get it aligned better. The foreplanes came together like magic. When I was done I had to run downstairs and show the wife. Just too cool.

[He Who Shall Not Be Named]

ARRGG! The prop shafts just about drove me crazy. Twice I glued the shafts in the after supports. Thankfully my wife had some nail polish remover to get them undone. I should have oiled the shafts so the CA wouldn't stick to them. One is slightly tighter than I want it to be so I may try some valve lapping compound and a low speed drill to get it aligned better. The foreplanes came together like magic. When I was done I had to run downstairs and show the wife. Just too cool.

Yes, you can use some laping compound and a drill to open up the stern tube bore a bit. But, what I do is to take a s**** piece of 1/8" rod, run a piece of #100 grit along it a few times, then use that as a reamer to open up the stern tube.

Not so much of a mess as compared to laping compound, with that oil suspended grit and gunk.

David,

[beeryboats]

Hmm. I don't have any s*** 1/8" rod, I'm new to building subs, but I may have an 1/8" aircraft drill. That would do it for sure.
David, the bow plane mechanism is pure genius! Works like a dream.
Jay

[He Who Shall Not Be Named]

Hmm. I don't have any s*** 1/8" rod, I'm new to building subs, but I may have an 1/8" aircraft drill. That would do it for sure.
David, the bow plane mechanism is pure genius! Works like a dream.
Jay

.

Trouble is, Jay, you don't want a close fit between the shaft and the bore, you want a few thousandth's of an inch slop between them. The 1/8" drill bit won't enlarge that bore enough to clear an 1/8" shaft.


If you have access to a decimal sized drill bit index, then select a .0128" sized bit and run that through the bore, that will give you the clearance (but still tight enough not to permit too much lateral motion) needed between shaft and bore.

I Qualified aboard a TENCH class boat and as a young-pup Torpedoman spent a lot of time under the deck preserving the tank-tops and other items within the superstructure (talk about hot, nasty work!). So, I know the retract mechanism well; we're old friends. I simply copied the real thing in model form.

But, thanks for the nice words ... never let that happen again!

David

[beeryboats]

I thought you wouldn't want much slop in the bores. Seems like I get one side all lined up, the white metal parts will bend easy, the other side binds up. I did bore the aft support out a little but it is so hard to keep them lined up with the longer forward exit tubes. I got them both pretty free now, but I'm afraid to touch the whole aft section or one side will bind up again.

[beeryboats]

I got lots done today. All the upper hull is cut out and cleaned up. I ended up using a hack saw to cut the ends off the sub. Much more control and less noise and stink. I was getting complaints from the galley about the burning smell and the dentists drill going constantly! I have yet to weigh the s****, but I bet it's a bunch. I reglued the hull and am letting it set for another day. Time to watch more of the DVD........ took all the removed plastic downstairs and got a weight, 5-3/4oz.

[He Who Shall Not Be Named]

That five-some ounces of topside weight lost will now get your boat up to designed waterline in surface trim when using our SD. Well done, sir!

Keep watching those DVD's.

There will be a test ... and it will be a *****! (name that movie).

David

[ADDINGTON]

Jim Brown in Ice Station Zebra ?