Build log
                                  by Ralph --- SSBN 598 
Most of the images have been resized to fit page format.
Right click on image and then click "View Image" to get full size image.
I will be documenting the conversion of a plastic kit submarine to a working R/C boat. 

Where to start?

How about with the Moebius, 1/72 scale kit, Skipjack.

Opening the box, I found several plastic bags of parts, instruction booklet and a sheet of decals.

Opening the bags and spreading out the parts. First thing you notice is there are really very few parts. 
2 upper hull
2 lower hull
2 sail pieces
1 sail top
12 control surface pieces
1 propellor
1 propellor hub
Assorted masts
Assorted clear lenses
Few other small parts. 

If this model was to be built as a stock display model, I think it could be completed in a few hours. Cleaning up the details and make sure everything fits together tightly shouldn't take all that long.

But this is not about building a display model. This will be a R/C model. The plan is to have working rudder, rear planes, sail planes and full ballast system. 

What is needed to make this model a working R/C model.

Before I can start collecting parts, I will need to decide on what type of ballast system I will use. I have decided to see if I can duplicate Tim's Sculpin build. His build was simple and very straight forward. He used a water pump and bladder ballast system. I have watched his videos and Tim's boat work very well. I would be very happy with having a boat the ran as Tim's Sculpin. I even like the color scheme. But that is something I will decide later. Lots to do before I start think about painting.

Parts needed. 

I have listed the parts I used including a link to the web page were I got them. The prices shown are the individual part price and does not include shipping.

Number of 
parts needed
  Part    Part from -----  Cost
1 3.5"x 24"  Polycarbonate Tube McMasters-Carr $33.94
Main Motor - Turnigy TracStar 21.5T HobbyKing $32.37
1 Main ESC - 35A HobbyKing $23.53
1 Pump Motor - Turnigy Park250 Hobby Partz $11.68
1 Pump ESC - 10A brushless w/reverse HobbyKing $11.70
1 Pump - Peristalic Roll Pump e-bey $  9.49
3 HXT900 9g mini Servos HobbyKing $  3.19
1 Main Shaft Seal  O-ring Store
3 Push Rod Seal O-ring Store
1 Transmitter - I looking for one. Mine is dead.      
1 Radio Receiver - Futaba R168DF 8-Channel 75FM Tower Hobbies $59.98
1 Rx crystal  Tower Hobbies $  6.99
1 Propeller  Hobby Inc $35.11
1 Battery Hobby Partz $15.74
1 SubTech FS1 Failsafe (lost signal) Precision Patterns $17.95
1 SubTech ALS Auto Leveler (pitch control) Precision Patterns $55.80
I have removed the major hull and planes from the sprue trees. I have washed all the parts to remove the mold release that is left on the plastic parts. I used a common household cleanser. This not only takes the mold release off but also took most of the plastic's shine off. 

Next, I cut off and sanded all the places the sprue was left on the hull parts to get them smooth. I plan to clean up the small dimples on the parts late, when I get closer to painting.

Image 1 - Rudder parts after cleaning, trimming and relocating the shaft notch.
Image 2 - Leveling the planes with pieces of 1/6" plastic sheet. 

Image 1

Image 2

While I had the Rudder in hand, I measured and notched the rudder to relocate the pivot point back 1/4". I know Tim said he did not do this but I couldn't let it go. 

I use this method of putting the shaft in so the two planes will be straight with each other to the shaft. Once I get the rods glue in place, I will cut the shaft in half. Trim shaft length to fit once the sail is ready for the planes. 

I turned a piece of sprue from on of the plastic trees to fill the holes in the upper and lower hull. Can be seen in Image 4.

Image 3 - shows the solid plastic piece I made to fit the tail cone. I stacked 4 - 1/16" rough cut squares. I used scissors. I drilled a hole the diameter of my propeller shaft and bolted the glues pieces together. After they dried, I use a disk sander to take all the corners off. Chucked it up in my drill press. and proceeded to make it round. Then with files I turned it down until it fit the tail cone.

Image 4 - This image is show how the turned piece is in place. Notice that I did remove the plastic from the upper and lower hull that is in the hull to hold the original propeller shaft. 

Image 3

Image 4

In Image 5 - I have put the propeller shaft through the new tail cone insert and placed in in the hull. I use a rod with a slight curve in it to hold up the in hull end of the propeller shaft. The curve is such that I can move the rod side ways and change the height of the propeller shaft to get it level . 

Image 6. This part will not be glued in just yet. I don't have the shaft bushings. Once I get the bushings, I will drill the tail cone insert for the bushing then with the propeller shaft in place I will center, level and glue the insert in the lower hull.

Image 5

Image 6

Sail planes are next. I have to build a connector out of 2 - 1/8" wheel collars.

Image 7

The sail Planes, Rear planes and rudders have been closed up and separated.

I have received all the parts except the water pump. They are on back order. I have the servos with their control horns. I will pick a set and then I can match the hand made ones for length of through. I then can soldier them to the wheel collars. 

Assembled Sail planes. 

Image 8





The building of the mast and scope Gizmo

1.  Laying out masts and new brass scope in sail. 
New brass scope is on left. Turned in drill press from 1/8" brass rod. Top of scope is a drop of solder shaped with file. I'll see if I can get a close up. Bottom or scope has 1/32" twisted fishing leader wire glues in to drilled 1/16" hole.
2.  Mast remove so we can see what's going on. Score lined up with 1/8"' ID brass scope sail tube. 
The wire is pushed through a 1/16" brass tube. Now I have to bend the tubing rather tight. The trick is to pack the tube with something you can get out after bending. I have used powder sugar and salt to do this on larger tubing bending projects. Thought about this and decided to use 1/32" solder wire. Not acid core and not flex used. I did put a short piece of 1/16" brass rod in the end of the tubing. I crimped in in with pliers leaving about 1/4" sticking out. I put a length of solder in the tubing with a little sticking out. I put the tubing over a stove burner and heated it. As it heated I pushed more solder in the tubing. When I ran out of solder sticking out, I used a piece of brass rod to push the solder down in to the tube to make sure the lower part was full. Let it all cool down. Then just made the bend needed. About 3/8" radius. Now the fun part. If you didn't use acid core wire or and flex all you do is heat up the end of the tubing and pull the short brass rod plug out. Then reheat the tubing half the length. The solder will start to drip from the down side of the tubing. While it is hot, just blow in to the tubing .... from the cool end and pointing the other in in to a can or something that won't burn. If you heated enough of the tubing all the solder will shoot out of the tubing. You now have a very small diameter tubing with a very tight bend in it. Check the tubing for obstructions by pushing the a piece of wire through the tubing. Not the scope wire in case you didn't get all the solder out. Reheat and try again.
3.  Scope going in to scope sail tube. The bent small tubing has a piece of brass tubing that goes over both the scope tubing and the bent tubing. This will be glued later later everything is in place and final fitting of all masts.
4.  Scope tube and wire tube attached with slip fit outer tubing. About 1/4" long.
5. Scope raise in sail.
6. Both halves of sail snapped together with left side plane in place for visual. 
Now working on Gizmo that will raise 6 masts. 4 will start to raise with out the other two. Then about half way up all mast will raise to full height.

Sail plane to sail step
1. Shows most of the parts are in place. Only four masts are in place. This will raise 6 total.
2. Mast are half way up but out of sequence. The top black plastic piece should still be where shown in first photo. 
3. The bottom black plastic piece comes up and lifts the upper black plastic piece raising all to maximum height. 
4. All the way up. All masts and scopes at maximum height. 
5. Looking from the front to see the individual masts and scopes. 

There is still a bottom plate to be made to keep every thing in alignments. The Gizmo is being built so it can be removed from the sail with two small screws. It should drop out the bottom of the sail if I get it right. 


Stern Plane ends.
Made from two layers of 1/16" plastic. The first layer is drill to accept the screws. The top layer is drill to counter sink the screw heads flush with outside of stern plane ends. 

Hull latches. 
These little things pull the top half and lower half tightly together as the upper hull is set in place and slid 3/8" back.

There will be one small bolt that holds the hull together. It will most likely be inside the forward center flood hole just aft of the anchor. Where the file meets the wooden sizing block is in the forward hull. 

All the latches and tabs in place. First coat of primer. Now the glazing begins.

Here is a photo of the hull having been glazed and sanded. Third time. 

I think I have reached where I want to be. Today, I will be filling the gap at the top hull Z-cut. You can see I have already taped of the tail cone, ready for filling. The filling has been put on the upper hull. Currently curing. 

I have to do this early because my mid day temperature is in the low 100° this week. Going to 105° by Sunday. By glazing early, I have been able to avoid the cracking that comes with drying to fast. The lower rudder is missing because I have not yet cut the control shafts to length. The lower rudder would be hanging down about 3/4". 

Here's a look at the hull painted. 
The gap at the top/bottom joints is there because I didn't close it up due to the paint being fresh. I left about a 3/16" gap. Didn't want the hull halves sticking together. I remembered to paint the control planes as well. 

If I don't scratch it up while working on the sail and the cylinder, the paint is ready for light fine light sanding for the clear coat. Which will be the last thing I do. Well, it will be before I do in water trimming. Just in case I need to do touch up. 

The tail group getting it's first topside black. 
I taped off the bottom surfaces and place a sheet of paper over the open hull during painting

Well, I had so many problems with the mast Gizmo trying to get masts to raise are different times, that I finally decided to scraped it. I also had thoughts of just not having them or mounting them prominently up. 

Yea, that's not what I wanted. So I finally thought I would give a second mast gizmo a try. All the mast will rise and lower together. As I built a new gizmo, I hit me .......... having all the mast rise and lower together looks to the observer exactly the same. The only difference is the short masts do not stop when they are just below the sail top. They continue down with the taller masts. So when the masts are down there will be holes in the top of the sail where yo can see the mast tops. 

Had I thought the original mast gizmo actions through, I might have caught this and made this change sooner. 

Now what you all really want.   Photos. 


Mid way


I have the Gizmo working on the bench. The control lines in next. In the photos the periscope is not in place. It goes in the brass tube at the front of the Gizmo. Everything works fine so I decided to put some paint on the masts. 

It looks like I can't put off cutting in to the top of the hull under the sail any longer. Need to get control rod through there and the control lines for the Gizmo. Just as well, I need openings to let the air in the hull escape when diving. 

Getting closer to joining the two sail halves together.

I did the sanding.
Made some adjustments to the Mast Gizmo guide rods. 
  (Got super glue on one of them and the brass tube would not slide all the way on. Removed it and made another)
With the repair completed, I sanded and filled the two little spots on top of the sail where the rods got through.
Touch up primer.
Final sanding and then some black paint. Nice ... except some fool touched the exhaust housing trying to stand the sail up to dry. 

I now have more sanding and more priming and more painting to do on the exhaust housing. 

I am beginning to think I should just leave all the dents and dings and scratches and call it, Returning from patrol look". 

Looking at the photo, I see a vertical line below the waterline at the aft end of the exhaust housing. Will inspect Tuesday. 
It feels like I am going to have enough filler and paint on this boat, I cloud have changed it's class. 

This morning I was in the shop redoing the sail. I got a piece of new sand paper. The one I had been using was filled with old primer and paint. Got my sanding block and a rag wet with water. I started in taking my time. Turned out I had enough paint and primer on the sail to sand out the dents and scratches without the need for glazing. Oh joy! 

Went to town and did town stuff. Came home and again went to the shop. Looked over the sail to make sure I didn't miss anything eye catching. Checked the wind out side and found a place where I was shielded from all moving air. 

Shook the life out of the black paint spray can to make sure I didn't get an thin or thick paint splotches. 

The results are acceptable to me. 

I have put off building the cylinder for as long as I can.

I have to make end caps.
I bought a 12" piece of PVC rod some time ago.
Now I need to cut it and then turn it to size.
The PVC rod is 1/6" bigger in diameter than the outside diameter of the cylinder. 

This should be fun.
I'm going to cut a 1" piece from the rod. 
Put a 1/4" hole in the center and use that as a guide to turn the cap. 

More photos as I start the process.

I have cut the disks for the three boats less one end cap as it is a bit different. 
More on that when I get to it. (Gotland will requires special end caps)

The two disks laying down are 1" thick.
The others are 5/8" think.
This may not be the finished thickness but it's where I am starting. 
The clear cylinder is the piece cut off the Skipjack cylinder. 
I didn't need the full 24".
Makes a nice piece to do the cap sizing with.
Don't have to worry about damaging the boat cylinder.

Next project is to make tool that I can clamp on to my drill press table that will be the cutting tool. 
The cutting tool will be stationary and I will use the drill press to move the cap up and down to remove material. 
After each cut I will move the tool in just a touch until I get close to where I need to be.

Then I will use a backstop to add .001" shims to move the cutter in. 
That's tomorrow's project. 
10:45am and the shop has reached 100F. 

Here's what happened so far today.
Got out to the shop early while it was cool.
Found a piece of angle iron that would do what I wanted.
Got out the 4.5" grinder.
I cut the bad end off to make it square.
Then made a band saw cut not all the way through. Then I took the grinder and removed the center piece leaving tabs sticking out.

In this photo you can see the tab sticking out and was ground in to a cutting tool.
The flat bar with the holes in it clamped to the drill press table is used to stabilize the long bolt the pieces are mounted on. There are several different size holes from past projects.

"Poor Man's Lathe"

Here, I have turned the end cap down and did the finish sizing with a block and 220 sand paper. 
I dropped the drill press table and check it again for fit into the short cylinder piece.
I took my time turning down the PVC.

The turned caps sitting on an original disk.

Here are the three caps needed. One end cap and two that fit inside the cylinder completely.

Caps set in the boat's cylinder. 

Now I need to find some 3.25"x1/8" O-rings. 

The other end of the cutting angle iron has a tab that has not been shaped yet. 
I will do that when the O-rings are in hand.
The tab will have a shoulder on each side of the cutting section.
The shoulders will control the depth of the cut. If I need it deeper, I will move the shoulders back as needed. 
This will allow me to just run the cutter in until it stops on the shoulders. 

Cutting the first groove will go slow as I check everything. 
I have a couple of practice caps for this. 

It took me two hours to make the cutting tool and turn 1 end cap and 6 internal caps. 
Each cylinder will use three caps. 
Still have one custom to make once I get there. 

Here's photo of most of what will go inside the cylinder.
Missing are the Auto Leveler, Lost Signal fail safe, a shaft connector for the main motor.

What's there. . . . left to right  ----->
1. Dog Bone universal for propeller shaft outside the cylinder.
2. Main motor Brushless sensored.
3. 35A ESC (main motor)
4. 5 micro servos (below main motor)
5. 30A ESC (ballast motor)
6. 8 channel Rx (below ESC ballast motor)
7. Ballast motor Brushless non sensored.
8. battery pack (below Rx)

Still an issue with finding a suitable water pump.
Well earlier this morning, during a little chat with Matt and Tim, I have decided to take on building my own roller water pump. 
Can I do it. Won't know until I try.
I have been waiting since Feb for three pumps I ordered. 
I can't continue the build without the pump so I am going to dive in. 
There are only two out comes. Good working pump or a bunch of parted assembled in to a paper weight.

I have a question of sorts.
Power switch?
The two ESC each have their own off/on switch and I will need a battery disconnect off/on switch.
With a battery disconnect switch, can I just ignore the switches on the ESC(s)? Just leave them on.

Note: I thought the ballast pump motor was broken when I took it out the box. I have never worked with brushless motors and didn't realize that the case spins around and only the shaft end is stationary when mounted. Surprise, surprise.

Sail Plane linkage and in sail bushings.

Shaft bushing glued in place and shaft. 

Shaft sitting in place. It will not be fixed in place but held there when the sail is screwed on the hull. 

Linkage sitting on sail.

Sail planes installed in upper control arm. Lower arm hanging out bottom of sail. When the sail is placed on the hull the linkage shaft will be put in bushing and the hull will hold it there.
Here's a look at the top of the sail with mast raised.

Boat with draft marks on. 
The lower rear part of the hull has not been buffed out yet. 
The spots on the upper hull aft of the exhaust housing are sunlight coming through ceiling vent. 

Control Rod Seals

I spent some time over the weekend looking all over the net for 1/8" shaft seals. 
Seems like everyone who made them in the past have given up on them.

Also while looking for parts I went through a box that had parts from my first submarine. 1988-9.
I found three old seals. Back then we had to make our own seals.
Basically it's a 1/8" ferrule tubing to 3/8" pipe brass fitting.
I had drilled out the pipe end to 1/8" so a brass rod would move through it smoothly.
You can see the original seal below.
It has the brass rod going through it. 

Old seal assembly from 1988-9 from my first working submarine. 
The other four fitting were bought this morning while in town. 
I found them at NAPA auto parts. Auto Zone has them but call them special Edelebrock fitting and want your first born for them. 
The fittings come with a brass barrel which I gave back the store.
I don't need them.

This photos shows the old seal assembly parts.
Three parts.
The two brass fitting parts and a single o-ring.
Only modification made back then was to drill out the 3/8" pipe side to accept the brass rod. 
Also used as a guide and bearing for the rod. 

This image shows the end of the fittings that needs to be drill. 
It's not much.
Second fitting from right is the old fitting that was drilled out. 

Once you put them in your end cap, you adjust them finger tight and then check for leaks.
You can tighten or loosen as needed.
Once you have it adjusted, you put a single small drop of glue on the nut and body of the fitting. 
Should you need to replace the o-ring or re adjust the pressure on the o-ring, you just cut the glue or twist it loose. 

Now for some technical information.
I dug the seal assembly out yesterday.
It has been in the box of parts since 1991.
The o-ring still has silicone grease on it.
I can find no crack on the o-ring.
The o-ring is still soft with pressure by fingers. 
The rod still slides back and forth easily with no hesitation. 
I can not blow air through the seal past the rod. 

I think the seal could be used today without worrying about it. 

My plan is to modify the new brass fitting by taking off the 3/8" pipe threads.
Drill holes in my end cap just deep enough to silicone glue the assemble in to the cap. 
This will reduce the weigh some and the hole needed will be much smaller. 

I paid $2.40 each for the new fittings at NAPA.
I check when I got home if I could get them cheaper else where.
Well McMaster-Carr has them for $1.70 each. 
Don't know about shipping costs.

I don't mind spending a little more to help local business. 

 End Caps

Bolt to make cutter is 5/16" hardened bolt.
Bolt is hardened bolt though I don't think that is necessary. 
Just happened to be what I grabbed. 
I cut the bolt head off.
I ground a flat side on the straight upper shank.
This is to get a good hold in the small vise I will use when cutting. It will keep it from turning or twisting in the vise.

I ground all sides where the threads were flat.
Next, I ground on the top and bottom of the cutter, down to the thickness of the groove cut I wanted.
I then filed the flats smooth and square with the shank.
Then I ground the end to an angle to help with the he cutting.
The cutter is just slightly smaller than the cut I want but I can adjust the height of the cutter to make the cut wider as needed. 
If the cutter wobbles at all then I hope to have room for this.
Once I make a test cut to see what I actually get, I can adjust the cutter by filing more off if needed. Or change the angle of the sides get a more square cut.

O-ring cutter in small vise.
First marking cut to check location.

Cutting to depth.
I would make a small cut and then remove the cap from the drill press and put an O-ring on the cap. I would do this several times to check fit in to cylinder piece. I know, I should just use calipers BUT each cap disk is a little different is size due to cutting free hand. So there is no standard dimension to go from. It only took 4 or 5 times to get the cut right. When I was close, I would use wet/dry sand paper wrapped around a round file to clean up the bottom of the cut and to take a little more material out if I needed to.

Here's the front cap inside the test cylinder with the O-ring on it. You might be able to see the dark wet line of the O-ring all the way around the cylinder contact.

Here is the center cap with it's O-ring in place showing the dark line of contact all the way around. You can also see that this cap has a recess of 3/8" to lighten up the cap and give more cylinder volume.

And there is the rear cap with the O-ring installed. Again I got that dark line of contact all the way around the cylinder.

Total time to put O-ring grooves in three caps.
Make the cutting tool. About 45 minutes.
Cut the three caps and fit O-rings. About 90 minutes.

It was less than the 90 minutes as I was doing laundry at the same time. 


Pumps ..... have been located.
I have them in hand.

Another poor man's solution to a problem.
I have for some time now, looked in to finding shaft connectors. 
1/8" by 1/8".
What I found was fine but at $4.99 each plus 4.75 shipping, I wasn't interested.
None of the hobby shops I get to have them in stock.
I have thought about get some brass rod and trying to make my own.
Even found a big brass bolt in my tool shed that I could use.
But there is always something that stops me.
This time I don't have a tap for the set screws.
To buy one would be as much if not more then the $10 connector.

This morning I was laying out all the electronics on the work bench to see what I have and don't have so I can start building an equipment tray.

While I was moving things out of the way, I saw an old sail plane control horn.
It's made from two wheel collars and two lengths of 1/8" brass rod.
They are soldered together. 
But I thought the solider wouldn't hold up with starting and stopping of a high torque motor.
After months of putting this issue off, the light came on.
Again the solution is so simple, I didn't think about it until now.
The solution will take 5 parts and I don't have to make but one.
Two others need modifying but I can drill a couple of holes.

So I got the parts and did the modifications.
And here it is for everyone to see.

Found and cut a 3/4" length of brass tubing the 1/8" shafts will go in to. (This is my standard control shaft bearing tubing.

I found two 1/8" wheel collars and two set screws.
Count them .... That's 5 parts.

Then I drilled the wheel collars holes to accept the tubing.

Next I drilled two holes in the tubing so the set screws will go through the tubing to the shafts.

Clean up the inside of the wheel collars with a small round file to debur so the tubing will slip through. With some effort. Tight fit. 
Put the set screws in the wheel collars.

Slip the connector assembly on to the motor shaft then tested the other end with a piece of 1/8" brass rod. (I need to get some stainless steel rod for this)
I now have a shaft connector made from spare parts.
It took me 15 minutes.

I thought about soldering the tubing to the wheel collars but then thought I do not want to have to go through balancing the connector. I have two razor blades mounted in a block of wood but why go to all that trouble.

If the set screw goes through the tubing to the shaft the tubing is not going to slip or turn.
 So this is how I made my poor man's shaft connector.


Just something to look at ........ 1/72 Skipjack behind 1/144 George Washington

What we are looking at here is the motor mount bulkhead and the two servos that will operate the Mast Gizmo and a periscope.

The motor with it's poor man's shaft connector 
propeller shaft going through end cap bearing
two servos

It's a start on the equipment for the Skipjack. 

Time to make the seal retainer. 
Some time back, there was a discussion about trying to imbed the seals in to the end cap.
Was it practical?
Well, I decided to give it a try.
I have materials to make another end cap if I have to but I/we) need to know it this will work and how much trouble it is to do.

Here is my end cap with the seal recesses in the end cap. 
I explained how I made the seal recesses cutters and cut the end caps on another web page. [url=]Cutter for seals[/url]

The piece on the right side of the photo is the 3 pieces of 1/16" plastic cemented together the other day.

The piece is already shaped but what I did was cut three pieces of oversized plastic that covered the end cap just below the motor seal. I used the end cap to trace the circle and then free hand the two tabs on the sizes. 
I roughed shaped the pieces with the drill sander disk. Then I used the small Dremel drum. Finally I used several different files to finish up the shaping.

While doing he shaping I thought about the air bubbles that might be trapped by the plastic plate. So, I beveled the bottom edge at 45 degrees to the cap. That should stop any bubbles.

Before I shaped the plastic I drilled an 1/8" hole where the motor shaft will go through.
I place an 1/8" brass rod through the end cap and the plastic piece to hold everything centered.
I then drilled an 1/8" hole using the top hole (rudder control rod) for a second brass rod.
Then I drilled the other needed through holes. 

Here the end cap is in my 3" piece of cylinder tubing with the seal retainer slipped on.
The two side tabs are for long brass tubes with bolts that will hold the front and rear end caps on should there be pressure build up in the cylinder that might displace the end caps. Tim had this problem. I thought I might try to avoid that problem now.

Control Rods

The cylinder is sitting in place using the hull frame and the end cap seal retainer as my guide to measure the control rods Coming out of the end cap are 1/8" brass tubing. On the inside of the cylinder the 1/8" brass tubing has 1/16" brass rod soldiered in to it. The 1/16" brass rods are fitted with nylon clevies that fit tot he servo control horns. The rudder and stern planes have the same 1/16" brass rod with the nylon clevies. A 1/8" brass wheel collar is soldiered to the end of the 1/16" brass rod and slips over the 1/8" tubing for adjusting.

In the photo you can see the two winch drums in place.

Top and Bottom hull safety bolt and lower tab.
   The tab is threaded.

There is a plastic block glued in place behind one flood port.
This block is 3/16" thick and sanded to make the curve fit the hull diameter.
The block is drilled so the bolt goes through with a little bit of room to move when aligning with t he up hull tab.
The bolt is a stainless steel allen bolt. IT was 1" long then I cut it off to what was needed.
The head of the bolt does not stick out beyond the hull.
I will paint it black at some point to hide it.

Started the plumbing from the ballast pump to the ballast balloon and to the rear end cap.
Here are the fittings I made from brass tubing.
The tubing will slip over the tubing and there is a ring that is one size larger that will stop the twisted wire that will hold the silicone tubing in place.

Top one is from pump on right to intake tubing on left. 

I also made a connector that will go from the pump to the balloon. The plastic pieces is so the balloon fits tight and when the tie wire is in place the balloon can't slip off the plastic.
The brass tubing extends past the plastic piece at this point because I don't know the final length just yet.
The plastic piece is not yet glued on to the brass tubing so I can slip it to it's final position.

Ballast balloon Containment Tank

After several days of trying to find a glue that would stick to various plastic bottles so I could use the screw on tops, my efforts ended in failure. No one of the glues or cements or bonders I have even thought about holding two parts together. I didn't even have to put any force on the parts. Just blowing on them caused them to fall apart.

So, today I decided to solve this issue from scratch.
I am going to make a bayonet twist lock.
Three lugs.

Cut a few pieces of sheet plastic and made a few pencil drawings.
Cut the plastic sheet in to squares, then I started turning them in to circles.

The photo below shows the containment tank ends.
The bottom of the tank will be flat so the battery can be slid under the containment tank.
Will also be running power wires under the tank.

The five pieces will become a what I need.
Access in to the Containment Tank to change the ballast balloon when needed. 

I have made the three lug capture ring and mounted on the Containment tank end.
Actually there are two rings. 
In the above photo, the thin ring is put on the cap first then the lug ring, allowing room for the center lug piece to turn and engage the lugs.

The center of the cap has not been removed yet because I am using the small hole in the center to keep everything in alignment as I go.

Here you can see the engagement lug on the brass tube.
Nothing is glues in place yet.
Still more fitting and making of parts before I can do that.

The circle on the left goes on last and will make the water resistant seal , should the balloon break the water should stay in the containment tank.

There are three 1/8" hole at the top edge of both end caps so the tank can vent pressure when the balloon is filled and drained.

Here the center lugs are sitting just above the lower lugs.
And before anyone points it out, Yes, the center lug is on backwards to show how it will fit.
The plastic piece at the top of the stack is where the balloon will be attached and will be on the other side of the lug so it goes inside the containment tank.

It was easier to photograph this way.

I should get everything assembled tomorrow and have a Ballast Balloon water Containment Tank.

Here is the bayonet three lug on the end of the tank.

I have assembled the tank end caps and bottom.

Still need to wrap the .02" clear styrene plastic sheet around the tank frame and trim the excess off. 
Currently letting it sit and cure before I start putting an stress on while covering.
After covering the tank will become rigged.
I will need to cut a notch on each end where the battery will slid under the tank bottom sheet.
There is room for a 2600mh LiPo

Wrapping the clear styrene around the containment tank end caps.

The clear plastic still needs to be trimmed flush with the tank bottom.
The battery sitting in place making sure I have room.
More than enough room for battery and wiring that will go under the containment tank.

Ballast Tank Containment tank slid in to the cylinder.
Battery will sit under the BCT.
I decided to have the water hose from the pump enter at the front.
This way when I open the cylinder at the front, I can disconnect the hose by turning the bayonet lug cap.
Pull the ballast balloon out and then I can each in and pull the BCT out with just one finger.
Also considered putting the BCT hose at the rear but then I would have to make sure the hose from the pump didn't interfere with the out runner pump motor. (Out Runner motor = the outside of the motor turns instead of the inside)
I was surprised when that happened ! ! ! 
I was holding it in my fingers when I tested it.
Also, I would need to open the rear cap to push the BCT out the front or rear.
Too much trouble. 

Assembling and Wiring....
Here the Electronics tray has been wired.
The Speed controller and Fail Safe circuit are not installed yet. 
That's next after lunch.
Then the main power wires need to be connected to the plugs and Off/On switch in the front end cap.

The new 10A speed controller arrived.
I will wire it in and test it.
The 10A was the original for this build but the one I have didn't work.
No reverse and the Fail Safe would activate.
If the 10A does not work again, I will temporally place the 30A in. 
It works.

Just realized.
The size of the 10A Speed Control compared to the 30A speed controller can be seen in the above photo.
The 30A and Fail Safe are in front of the cylinder.
The 10A speed Controller is sitting under the stern of the boat. 3 blue wires and the battery wire plug.
The 10A speed controller is no bigger than the Fail Safe circuit board. 

Should be able to complete the wiring today and tested.
Then I can grease up and install all 5 O-ring and the 1 cup seal in to the rear end cap. 
Water Testing.

Well, I tested the new 10A Speed Controller.
It works.
Soldered every thing in and .... WHAT? .... the 10A speed Controller failed again.
It runs in both directions but it lags the Tx stick control by 2 seconds or more.
The motor runs very slow (it cogs) and then stops after a few seconds.
I though maybe the battery needed charging.
Charged it up to full.
No change in the pump motor.
So, I will be removing the 10A Speed Control and putting the 30A Speed Control in.
Fortunately, I have room for it and I built a platform for the 30A Speed Controller when the first one did not work.
I didn't plan on the new SC showing up in time.
So, first thing this morning, I will remove the 10A and put the 30A in.
Maybe 15 or 20 minutes for the redo.

Changed out the Speed Controller.
Motor failed again.
So, I changed out the motor.
Ah, now it all works.
While I had every thing apart on the bench, I removed the 30A speed Controller and put the 10A SC in.
It works too.
So my ballast tank problems was the motor and not the Speed Controllers.

Disassembled all the ballast system parts.
Did this because during the testing the parts where not on the electronics tray and wiring needs to go through some holes in the tray to get where they need to be. So, I started assembling all the parts again and making sure to slip the shrink tubing over the wires as I went. Got it all back together and... you guessed it. Testing again.

Everything works.
Okay. Time to move on.

Ballast system.
The water path parts.
Got the balloons that go inside the Ballast tank containment tank.

Containment tank and balloons.

Here the piece that holds the balloons to the pump line removed from the containment tank.
This is where the bayonet lugs come in to play.

Putting one balloon inside the other.
This is a safety item recommended by Tim. 
I'm basically copying Tim's build so two balloons it is.

Balloons mounted to the fitting on the bayonet fitting.

By making the bayonet lug cap allows me to get the balloon in to the containment tank.

1/3 turn and the piece is locked in to the containment tank.
This photo is with the balloon filled with air checking for leaks.

Ballast Balloon problems.
During water testing, the ballast balloon filed as it was suppose to.
During emptying, no water was pumped out.
I had to remove the ballast safety tank with ballast balloon inside.

I found the problem. 

This is the ballast safety tank and the ballast balloon with it's tank end fitting. (bayonet lock)
The nylon tie wrap has been removed.

Here is the problem.
During emptying the ballast balloon the neck of the balloon folded over and covered the hole to the pump hose stopping the water from leaving the ballast balloon.

I have made a brass tube extension and a plastic piece to be shaped.
The tube has holes in random spacing.
This tube and plastic piece should keep the balloon stretched out enough to keep it from folding over and with several holes, it should always be able to pump water out. (we will see)

Here, I have started shaping the plastic piece.
Well what would be a day be with out some issue coming up.
Got my Gorilla glue out of the cabinet and it is solid.
Good thing I am going to town tomorrow morning.

Plastic end piece shaped.
Need to smooth the brass tubing joint a little more.
Will drill two more holes and then glue the brass in to the plastic pieces.

Second water tested.
There is a leak again.
First I thought it might be any of the many o-rings.
But with t he ballast balloon full there was positive pressure in the cylinder.
Need to look else where for the leak. 
Opened up cylinder.
Removed end cap and disconnected battery wires and switch.
Removed battery.
Slipped electronics tray out rear of cylinder along with the ballast safety tank with full ballast balloon.
I looked and did not see water around or near seals.
Let it all sit until dry.
No water seen.
Plugged in battery and turned on Tx & Rx. 
Cycled controls and started emptying ballast balloon.
I reversed the motor direction to get the fast for filling and the slow for emptying.
Water was draining out the rear cap brass tube.
Aft a few seconds I could see water at the pump end of the electronics tray.
Closer inspection, I found a leak.
The silicone tubing from the rear end cap to the pump has a pin hole in it.
Under pressure it opens and drips.
Here it is.

Time to make lead ballast bars.
I use a 2" piece of steel channel iron.
I cut wood blocks that fit inside the well tight enough that it requires a couple of traps with a hammer to set the blocks all the way down in the channel.
Here, you can see I have leveled the table.
  The table has been sitting in this location some 30+ years and has built a lot of projects.
Over time the table legs even with 2"x6" blocks under the legs has sunk on once side.
The table has a 2.5" slope over 30" width.
Foreground has lead sinkers and scrape that I will be using.

Ready to start melting the lead in to the mold.

The process has begun.

Three bars completed.
The top one is 1/4" thick.
The Middle one is 3/8" thick.
The one in the mold, I'm not sure but it looks like it's more than 3/8" but not 1/2" thick.
Once I figure the needed weight during trimming, I will cut the bars in pairs.
I will cut them so they fit between the plastic ribs in the hull..
I use a band saw and bee was to cut the lead.

After I get the length correct, I will using a big bench vise, hammer them with a curve to fit the hull shape.
Doesn't need to be perfect because the silicone glue will fill the gaps.
Might even fill enough, I won't need to bend them.

While waiting for the lead ballast bars to cool off enough to handle, I took the time to mask off and painted the inside of the hull(s). Both the top and bottom.
Photo is the top half or the hull.

Isn't that pretty.
Completed assembled Cylinder!

Sail Planes Control Rod Connector
On Left is control rod end that go on push rod from servo.
At center are two magnets. (4 pieces)
On right is the sail planes lower control horn.

Magnets mounted on Control rod end.
These will be mounts solid in a straight line with the control rod.
The magnets that go on the control horn will swivel to self align to the control rod magnets.
The long control rod will be held on top of the cylinder by a small length of velcro strap with a loop in to allow it to move up and down to attach to the control horn magnets without friction.

Sail Planes connecting Rod .... completed and tested .... several times to get the final length.

Water Testing ........ No Leaks found.

Cylinder was on surface. 
Operated all the controls.
Removed from water to inspect thoroughly.
Looked for leaks. 

Back in the water and left for 30 minutes on surface. 
Checking often, just in case.
Operating controls.
Removed from water and found no leaking.
Back in the water and fill ballast balloon half way.
Cylinder lowered in the water as expected.
Removed from water and checked for leaks. 
Still good.
Back in the water to fill ballast balloon more.
At about 3/4 full the horrible sound of the pinion gear slipping on the motor shaft.
Checking to make sure this is what was happening, the pump housing is clear on one side, to check is just a matter of rolling the cylinder over and looking in to the pump housing.
Sure enough, the pinion gear is slipping.
Decided to continue leak test by weighting down the cylinder so it sat on the bottom and completely submerged.
Left there another 30 minutes.
No Leaks.
Home made cylinder and end caps passed the test.

Now I need to open up the cylinder and remove the ballast containment tank with the ballast balloon inside.
Once out of the cylinder, I can drain the ballast balloon.

Then I can open the other end of the cylinder and slide out the electronics tray.
Remove the pump.
Open up the pump housing and check the pinion gear more closely.
The solution I plane to use is to run the motor and using 100 wet and dry sand paper, take the shine of the motor shaft.
Then apply a very small drop of water proof glue.
Press the pinion back on and let it sit.

I can do that and reassemble the pump.
Put the ballast system back in.
And seal it up.
Won't run any of the systems so the glue can dry completely with out me mistakenly operating the pump motor.

With the cylinder sealed up, I can move on to surface trimming to get the needed lead ballast set and foam.
Then to do submerged trim is just a matter of moving the weigh and foam around to be the boat level submerged.

Ballast Pump Issue.

I disassembled the pump. 
Sanded lightly the shaft.
Glues the pinion on the shaft.

Took some time away from the boat to work on my truck. 
Had to fine why the running lights did work.
5 minutes and that problem was solved.

Went to town to get stuff to make lunch to take with tomorrow.

Put pump back on the electronics tray.
Test ran the pump.
Things are good.
Put every thing back in the cylinder and sealed it up.

Put the cylinder in the lower hull.
Hooked all control rods up.
Place the top hull on the lower and buttoned it up.
Oh, I did turn on the Tx and then the Rx to make sure all still worked.

I took my best guess on how much ballast lead was going to be needed.
Missed by one short bar too much.
Removed it.
Moved the other bars back about 1" to correct for surface level.

The boat now sits about 1/4" high and level.
The scribed water line is above the surface.

Now the submerged level.
Well, that's going to have to wait.
The pump will not run once water gets in the feed line.
At that point I remember Tim said he changed to a different type of feed hose.
Of course I knew that because I read it when he posted it.
But I forgot about it.
That was almost a year ago when he tested and came up with is parts list. 
My mistake...I forgot.

There is nothing more I can do about the ballast system tonight for tomorrow's Fun Run.
So, I removed the battery from the boat and put in on the charger.
Put the Tx on the it's charger.

There is still lots to do on this boat before it's finished.
But, I have a perfectly good surface runner at the moment.

That's how it's going to the event.

Oh wait..... one more things. .....

In the water....
Skipjack's first in the water trim test.
The boat was a little heavy and I removed one small ballast block and 
hit right where I want to be.... when I start submerged trimming.
I'll problem add the small ballast block back in and add some foam to trim the submerged level in.

Update. . . . . . . . .

At this point the boat is operational.
I changed the water pump tubing to a larger inside diameter as recommended by Tim and Matt.
This fixed my pump issues.
I am currently back working on t he Mast Gizmo and Periscope Gizmo.

I have made changes to the Mast Gizmo.
It was binding so bad that it would hang up about half way up or when all the way up, it wouldn't come down without extra effort by touching the masts with my fingers.
The changes worked.
I went on to making the parts needed in the hull to guide the lines to the winch.
This photo shows the brass rod line guide for the Mast Gizmo.
At the ends of the lines are disconnects and there is a length of elastic string from one connector to the other via a brass eye at the front of the cylinder mounted to the front end cap.
This keeps tension on the lines so they don't unwrap from the winch spool.

In this photo the two brass eyes at the top guide the lines to the Mast Gizmo.
One is for up and the other is for down.
The bent brass is the periscope push cable guide tube.

The tube is made up of two different diameters.
One slips inside the other.
There is a full up stop ring on the left side.
The periscope bottoms out as the stop for full down.
This photo shows the position of the tubes when the periscope is all the way down.

Sorry this photo is blurry.
It does show the tubes position when the periscope is all the way up.

Masts and Periscope all the way up.

Mast half way up or down.
Your choice.


Mast almost down.

Mast all the way down.

I did get the periscope to go up and down twice.
Then something happened.
The winch did not slip as it was suppose to. 
The up line broke.
Not sure what happened.
Have some ideas.

1. I had the lines crossed. Up was down and down was up.
    Only thing that should have been effected was the Tx control knob direction.
2. One of the connectors may have slipped between the cylinder and one of the frames.

I will have to look in to this issue.
One thing I will do is paint the connectors so I know which pairs mate up.

Again something to look at. george Washington, Akula II, Skipjack.