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Hello fellow members,
I have completed the hull of my OTW 1/32 U-Boat, and I have been working on a design for the WTC and ballast system. My hull is designed such that I can place a 3.5 OD x 36 inch WTC into the hull just by removing the tower section (8 brass machined screws). However, I would like to limit the WTC length to as close to 32 inches as possible.
I have designed a dive system that uses an SES-II (to receive the dive/blow commands) and my own TTL logic circuit to activate two Solid State relays with 2 open contacts each. The relays will determine the water pump motor flow direction, as well as pulling a valve solenoid. This is fairly simple stuff.
I figured the ballast tank size to be 20 inches long, 19 inches internal free flood space. The pump motor is similar to the one used by OTW in there WTC which can pump up to 2.1 bars (30.5 PSI). If my math is correct, then my ballast tank has an internal capacity of 155.8 cubic inches (a little less because of 3 internal baffles). At 60 percent capacity, the intermal pressure should be 2.5 PSI, and the ballast weight of 2.46 pounds. At 70 percent capacity, the internal pressure should be 3.3 PSI, and the ballast weight of 4 pounds.
I plan on using a pressure switch to kill the pump circiut when the preset capacity is reached. In addition, when the tank is being blown, there is a water sensor that will stop the blow when there is no water at the exit drain. With this design, I can use a three position switch to control the TTL ballast system (dive - open - blow) at the transmitter. The pressure switch and the water sensor provides feedback to the TTL dive system.
Now, on to my inexperience....
Do I have enough remaining space for everything else (Receiver, SES-II, APC-4, ADC-1, 3 servos, Voltage circuit, pump motor, solenoid valve, Dive circuit & 2 SS relays). I plan on placing the dual brushless drive motors and power amp at the drive shaft level in separate enclosures.
I would appreciate any help and comments... Like I said, I may be all wet, but I think it's better to ask advice, then to sell the farm, and then be up the creek without a paddle. I did that once and purchased a Dual Engel Piston dive system and discovered that it won't fit! I was very lucky and sold them and broke even (never again).
Regards,
Don_
Edited By Don Prince on 1132525491
I have completed the hull of my OTW 1/32 U-Boat, and I have been working on a design for the WTC and ballast system. My hull is designed such that I can place a 3.5 OD x 36 inch WTC into the hull just by removing the tower section (8 brass machined screws). However, I would like to limit the WTC length to as close to 32 inches as possible.
I have designed a dive system that uses an SES-II (to receive the dive/blow commands) and my own TTL logic circuit to activate two Solid State relays with 2 open contacts each. The relays will determine the water pump motor flow direction, as well as pulling a valve solenoid. This is fairly simple stuff.
I figured the ballast tank size to be 20 inches long, 19 inches internal free flood space. The pump motor is similar to the one used by OTW in there WTC which can pump up to 2.1 bars (30.5 PSI). If my math is correct, then my ballast tank has an internal capacity of 155.8 cubic inches (a little less because of 3 internal baffles). At 60 percent capacity, the intermal pressure should be 2.5 PSI, and the ballast weight of 2.46 pounds. At 70 percent capacity, the internal pressure should be 3.3 PSI, and the ballast weight of 4 pounds.
I plan on using a pressure switch to kill the pump circiut when the preset capacity is reached. In addition, when the tank is being blown, there is a water sensor that will stop the blow when there is no water at the exit drain. With this design, I can use a three position switch to control the TTL ballast system (dive - open - blow) at the transmitter. The pressure switch and the water sensor provides feedback to the TTL dive system.
Now, on to my inexperience....
Do I have enough remaining space for everything else (Receiver, SES-II, APC-4, ADC-1, 3 servos, Voltage circuit, pump motor, solenoid valve, Dive circuit & 2 SS relays). I plan on placing the dual brushless drive motors and power amp at the drive shaft level in separate enclosures.
I would appreciate any help and comments... Like I said, I may be all wet, but I think it's better to ask advice, then to sell the farm, and then be up the creek without a paddle. I did that once and purchased a Dual Engel Piston dive system and discovered that it won't fit! I was very lucky and sold them and broke even (never again).
Regards,
Don_
Edited By Don Prince on 1132525491
Of course, these figures reflect the absolute pressure in the tank, meaning that when the tank is empty of water, there is already about 1 bar in the tank (actually 1 bar = .9869 atmospheres, but we should be close enough for discussion purposes). These means you need to subtract 1 bar from your final number to see what a guage would read if you measure the tank pressure. Follow?
And using a pair of chips and FETs I can plug directly into my receiver, bypassing the need for the SES II entirely.
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