David. I would hugely appreciate that. Your photos were very helpful. Thank you.
The quality of parts, especially resin castings, are excellent, and I understand that continuous improvement can quickly outpace documentation. The PDF’s I had been pointed to are the Seaview implementation, and almost entirely just of the SD assembly.
This unit is ultra compact. If cutting the servo lugs off is what I should do, then OK. I was unsure.
What would really help me most at this point is a basic generic block wiring diagram showing which leads go to where, I only had wiring connection info with the ADF2 angle driver and snort pump. Are front and rear dive planes on separate servo’s or combined? Do planes work in the same direction or opposed? Motors rudder and planes are on the Tx sticks, but should gas bottle and snort be from sliders or on/off switches?
Is Rx wired from main battery (I assume 6V), or separate battery pack. Is there a recommended battery, weight being critical.
I got the recommended WFLY FT06-A, which was an amazing price for a 6 ch 40Mhz system, but I was not able to obtain the later required Sombra Labs TL-8 receiver as they don’t make a European 40Mhz version. I have just bought a Robbe/Futaba F14 six channel 40Mhz system to replace the WFLY which I hope will be suitable.
Do Caswell stock magnetic couplings? I have been unable so far to find any over here. If not I can make them.
I've provided below some shots that will help guide you as you install the devices on the foundations attached to your motor-bulkhead. Note that almost every item in the after dry-space is semi-permanently attached, in one way or another to the motor-bulkhead; when the motor bulkhead is installed/removed from the cylinder, the entire assembly moves as a unit. The only make up to the cylinder being the two power cables from the battery-switch harness, and the lead from the ballast sub-system servo -- other than those two items, all propulsion and control hardware is mounted to the motor-bulkhead.
The below block diagram illustrates for you how the leads between the various devices connect to one another. Note that the receiver is the nexus point for most of what is going on in the SD; it is through the receiver bus -- fed from the ESC's BEC -- that the required five-volts is distributed to the other devices that make up the system.
Never connect the stern planes and the bow planes on the same linkage. Those two sets of control surfaces do two different things: The bow planes contribute little angular moment to the submarine, but they do push the vehicle up and down -- they are used for depth control. If you're inclined to employ an ADF, that device is placed between the receiver and the bow plane servo.
The stern planes of a submarine contribute mostly a pitching moment to the vehicle (the phenomenon of 'Chinese planes' aside for this discussion), so they are employed to set/maintain/alter the boats pitch angle, the 'bubble'. Just as helicopters require some artificial stabilization and damping about the yaw axis, a submerged submarine needs autonomous control of the pitch angle. You stick the angle-keeping device (in our case, the angle-keeping leg of the consolidated ADF device) between the receiver and the stern plane servo.
Don't mix, mechanically or through the transmitter, the stern planes and bow planes.
Here's the assignment of stick/switch/knob transmitter controls to the functions aboard your model submarine:
ch-1 rudder (right stick, left/right motion)
ch-2 bow planes (right stick, up/down motion)
ch-3 throttle (left stick, up/down motion)
ch-4 gas ballast sub-system (left stick, left/right motion)
ch-5 low pressure blower/snort
ch-6 stern planes
Here's the arrangement of the devices aboard a 2.5 SD. Once thing I would change: I would put the fuse between the battery and the input side of the ESC.
You're biggest challenge is running the 1/16" brass pushrods through the motor bulkhead watertight seals. Here you get some appreciation on how creative you need to get when bending these things to make up to their respective servo bell-cranks without binding, or getting in the way of the centrally located receiver
Just some of the tools I use when bending servo pushrods to shape.
Note that the central area over the cast resin servo foundation is open, ready to accept the systems receiver.
The Kli-Con magnetic couplers -- that interface between the SD pushrods, and the control surface pushrods -- shown here. Yes, they are stocked by Caswell Inc. Note the Dumas couplers (3/16" bore) attached to the two motor output shafts. The two 3/32" tubes atop receive external hoses that lead to the ballast tank and the induction intake up in the sail -- a portion of the LPB/snort ballast sub-system.
While tweaking the bends in the pushrods to achieve minimum binding I made good use of a 'servo-setter' device. Or, you can hook up the receiver and battery, and twiddle the sticks from the transmitter as you work to reduce the drag between pushrods and watertight seal gland.
I prefer to attach the servos with RTV adhesive/sealant. This holds them fast within the cast resin foundation, put will part if you need to yank the servos out of there.
Just some of the devices that attache to the motor-bulkhead foundations. Receiver, ADF (angle-keeper and fail-safe circuits on one board), and ESC. Not pictured is the LPB pump-motor and its attached MPC (motor pump controller), and Lipo-Guard (commands a blow before the Lithium-polymer batter voltage drops below the critical (destructive) level.
Bottom aluminum sheet foundation. This is where the LPB and its attached MPC are mounted with servo tape.
An outfitted 2.5 SD. The ADF is servo-taped to the side of a servo. The Lipo-Guard is so mounted on the other side. Note that the receiver fits between the servos, atop the cast resin servo foundation. The ESC attaches to the forward face of the device bulkhead.