OK. Finally got some pics together.
Really wish I could start this whole project again, as I would approach it differently. But hey... its something to do.
As you can see.. WAY more complicated than it needs to be (but I build everything like that!)
There are a pair of clear pipes running outside the WTC. The one front the front of the WTC to the rear feeds the ballast balloon (temp green balloon at moment).
The other clear pipe links the front of the WTC (Pump and radio room) to the rear WTC (Engine room). Just to give me some more volume of air.
I will change these pipes to R/C fuel line (and shorten them) later as its much more flexible.
The link pipe from the radio room to the engine room, could in theory, be my vent pipe when I charge my 7.2v battery in the Radio room. If I just remove the pipe, then I have a vent.
Therefore, I will fit a waterproof charging socket somewhere along the main battery feed (large cable running outside the WTC).
The reason the pipes and main battery lead run outside, is it made breaking the WTC in half a lot easier. But that was when I fitted it through the top of the sub.
That turned out to be a pain in the backside, so I have now made the rear of the sub come off instead.
The three servo brass rods (currently folded back above the radio room) control the front planes up/down, fold the front planes and open/close the torpedo doors.
At the rear of the sub are the usual 2 servo rods for rudder and rear planes + 2x prop shafts.
There is a large blank PCB board in the engine room. Ignore the mess of wires everywhere... nothing is connected yet.
This is where my custom PIC chip ADC+APC module will go. I have written the software for my own one. Also, I will put the magnetic on/off switch here.
The circuit includes a battery changeover circuit that will feed the radio gear from the 7.2v battery, if the receiver battery dies. It will also trigger an emergency surface.
The cables hanging out in the midships go to the conning tower for some 'effects' .... snigger. They come much later on!
The whole thing seems to float fine and the ballast system works well.
My only concern is if I have room to get enough buoyancy around the WTC. There is room, but I don't really know how much I will need (but I have done some trials). Plenty of room under the WTC for lead ballast.
Like I said. If I started again (which ain't happening)... it would have no external pipes or wiring. I hate untidy builds.