Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Submarines => Topic started by: sub john on January 08, 2021, 10:30:25 pm

Post by: sub john on January 08, 2021, 10:30:25 pm
HI Guys
        I hope you have all been busy doing your projects during this lock down.
        A good friend of mine gave me one of the otw upholder model submarine, it had even got the tube with it and the 40mhz radio but my friend got so far through it and lost interest in building it, but as i have started to build it the first problem i came into when you filled the centeral ballast tank as it came to about half full the water pump would slow down to the point where it could not put any more water into the tank because of the pressure build up, even as though the tank had got a small pin hole at the top of the tank to let the air into the rest of the tube and the water sensor sits just below it to stop it filling so water does'nt go in to the rest of the tube. But no matter what i did the tank would not fill more than half full it would be interesting to know if any one else has had the same problem. even i stript the water pump down and rebuilt it and the water valve it still did the same, had a problem with the control board for the pump it decided to let the magic smoke out enough to say the board blow up, but the tube leaked and water got into the board ended up stripping it all down again and repaired and rebuilt the circuit board. The other problem i had was the cut out voltage on the board was the wrong voltage for the batterys i was going to use moded that and it now works for what i need it to do.

      I  Have done alot of modes on the tube inside one is when the sub dives the water sensors that was in the top of the ballest tank  now has a small seperate tank with the water sensors in that there is one way valves so what happens is the tank fills so much with water then switches off the pump, the pressure build up inside the main tube is vented out through a snorkle with sits inside the conning tower so the air pressure goes back to normal pressure one bar, the snorkle is fitted with electro valve and all so works as a mushroom valve the mushroom valve works in such a way even if the tube heats up it lets air out to keep it at one bar pressure. When you blow the main ballest tank the first thing it does any water that has built up in the small seperate tank it sucks that water back into the ballast tank to pump it out as the pump starts to suck the water out of the main ballast tank the main tube in depressurized but as soon as the snorkle clears the surface of the water in the conning tower the snorkle opens and puts the pressure inside the tube to one bar normal air pressure There is another small over flow tank that is connected to the snorkle so if any droplets of water comes in the next time you dive it is blown out thrugh the snorkle
 I don't have any more problems with the tank only half filling now and the tank now fills alot faster, the beauty about having a sub as small as this you can try the tube in the bath which make life easy  not like trying to put a 12ft gato in the bath     even the engal gato won't fit hope some body finds this interesting

                                         All the best Sub John      ps i did'nt think i would build another sub again but it just goes to show
Post by: salmon on January 09, 2021, 05:02:14 pm
Personally, I am glad to see you building another sub. Mainly, I think you need time by the pond. Moving the Gato was never a one man operation. This will be. Plus, I like the fact that your creativity is engaged on this. Look forward to more posts (with pictures!).
Post by: Subculture on January 10, 2021, 01:37:29 pm
Have to smile when someone describes an OTW Upholder as a small boat.
Post by: sub john on January 11, 2021, 08:53:14 pm
HI Tom
        Thanks for reply, to be honest i have not long finished building a mosquito model plane three people have been asking me to sell it to them. But going back to the upholder i won't to do some more work on the hull and conning tower but it is to colled to be out in the garage don't won't to be using super glue in the house where the reptiles are, it would not do them any good. Hope you had a good Christmas ours was quite did'nt see the family
                                                      All the best John
Post by: sub john on January 11, 2021, 09:02:48 pm
HI Subculture
                You said it makes you smile when somebody says a upholder is small but to me it is small i can pick it up with one hand and if you put it at the side of the big Gato it looks as if a bit has droppted off the big sub on the floor, and even the engal Gato i look at that has small but this is smaller, these smaller model submarines look like airfix kits to me but thats what you get when you have a big sub 12ft long, to give you some idea somebody asked if they could come round to see the sub he asked how heavy is it and i said to him just try to pick the front up and he could'nt lift it, he was very supprized just how heavy it was. But it did make me laugh
                                 All the best John
Post by: sub john on September 03, 2021, 11:41:29 pm
HI Guys
         Thought i would do a up date on this a few weeks ago i finished building the upholder and the updated diving system, works really well the snorkel system that i did for it even compansates for pressure changes at different depths i must say i have never been keen on the tube system but after seeing this work i am suprised how easy it is to get ready to go sailing. On the bench a few weeks ago started to build trim tank system with just one tank can be front or back of the sub self leveling useing giro and solid state electronics water is took into the trim tank from the water out side the sub. Just say you fired a torpedo out of the front of the sub because the torpedo would be slightly boyant as it left the sub the front of the sub would tilt down but with the trim tank system it would compansate  for it very quick, but the giro to control this has to be very sensertive it can move large amounts of water of very small amount

                             Sub John
Post by: Martin [Admin] on September 04, 2021, 12:09:45 am
I had a Darnell Upholder ....   :-),48368.msg491019.html#msg491019