vdt prob

Discussion in 'North Atlantic Treaty Combat Fleet' started by JasonC, Jul 5, 2008.

  1. JasonC

    JasonC Active Member

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    ok did testing on vdt today pump is below 1gpm so saft there but the is running at 24 and has to slow down to 36 so i know drag props will not work so what size prop am i needing i got 1.25" 4 blade 40 pitch so what yall think i need?
     
  2. bb26

    bb26 Well-Known Member

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    I would try going to 3/4 inch props and maybe some drag props
     
  3. djranier

    djranier Well-Known Member

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    What gearbox are you using? The BC GB500 by chance. It comes with a 14 tooth pinion, but BC sells a 12 tooth that will slow you down by a additional 2 to 3 seconds. and I think you can find 11 or 10 tooth on line also.

    The smaller prop, with 25 pitch will also help, then you will have to use drag disks on the outer shafts to help even more. It will take you numerious trials to get it right.
     
  4. Powder Monkey

    Powder Monkey Active Member

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    i'd try gearing if it is an option than go from there
     
  5. crzyhawk

    crzyhawk Well-Known Member

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    On my treaty Invincible, I'm using 550s on direct drive with like 1.25 inch props with nearly no pitch and it works pretty good.
     
  6. JasonC

    JasonC Active Member

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    ya sorry im running her at 6v and driect drive
     
  7. Bob Pottle

    Bob Pottle Well-Known Member

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    Jason,
    Are you using threaded or plain prop shafts? Tom has an issue with non-threaded shafts on Nagato so he's going to remove them and we'll cut them for 4 mm threads. Then he can try several different size Rivabo props in my stock (including 3 and 4 blades) until he gets the speed close. He'll fine tune it with drag discs on the outer prop shafts if necessary.

    If you can't switch props easily try setting the speed with drag discs on the two outer (dummy) prop shafts.

    Will mail the 1/16" hose to you this week before I leave for vacation. Forgot to last week. Sorry!

    Bob
     
  8. JasonC

    JasonC Active Member

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    ok, took vtd and new jersey to the pond this evening. i put 1.5" drag disc on vdt. the speed is now 36 just where i wanted he sound a bit like a vacuum but it will work 4 now. new jersey is running at 32 seconds witch is slow but i think i had was near dead battery.
     
  9. Bob Pottle

    Bob Pottle Well-Known Member

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    Sounds good Jason. Tom is putting smaller props on the Nagato and if it's still too fast (should be 33 seconds/100') he'll add drag discs on the dummy shafts.

    We may do a test on his pump and my four Wednesday evening. Speed tests of the Minotaur, Black Prince, Gorgon and Prince Robert will be done in late July when I get back from vacation.

    Bob
     
  10. HMCS

    HMCS Active Member

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    Hi all,

    Question for you, how does one go about testing pump flow? Is it as simple as measuring the amount of water over a minute period or something more then that?
     
  11. JasonC

    JasonC Active Member

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    i put a gallon of water in my boat and timed it
     
  12. crzyhawk

    crzyhawk Well-Known Member

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    when we tested pumps last year what we did was pull the pumps out of the boats and hold them in a pot full of water with a gallon of water in it. If it pumped all the water out in faster then a minute we were too fast. Otherwise, we were too slow. We had a container that we measured out an extra quart of water that we added to the pot as it was being pumped out for testing battleship pumps.

    Just pouring the water in your boat works too though!
     
  13. HMCS

    HMCS Active Member

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    Perfect.

    I figured that was all there was to it. But I always like to ask (even if it makes me sound dumb)just to make sure I have everything straight.

    Question for ya Mike.... 3 unit cruiser, Treaty rules, how would you place your cannon? I'm thinking triple sterns(1,1,1/2)good damage ability, but with only scoring sinks may lead to a lot of aboves which don't count for much, Dual sterns and 1/2 unit bow gun, still gives you a sting in the stern but adds a bow gun,which if angled 15 degrees may result in a few On/Below, 1 unit stern gun, 1 unit 15 degree bow gun B turret port,1/2 unit 15 degree bow gun A turret starboard, a bit unusual but my thinking would be with the speed advantage you may be able to use the bow guns to good effect ,scoring some On/Below and contributing to victory by being able to help sink an enemy ship.
     
  14. Bob Pottle

    Bob Pottle Well-Known Member

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    Jason and Scott,
    When testing the pumps remember to use American vs our larger Imperial gallons! An American gallon is 128 oz. vs 160 oz. for our gallon.

    Tom and I used the pan, pump and measured amount of water method. We were able to calculate ounces pumped per second and the exact pump capacity per minute.

    Bob
     
  15. slow_and_ugly

    slow_and_ugly Active Member

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    Hi Jason
    I have been famailiarizing myself with the rules and unless it's been changed there is rule that states that the drag props can't have a larger diameter than the drive props.
     
  16. HMCS

    HMCS Active Member

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    Rob that is correct about the drag disks. There is even a sentence in the rules that states drag disk can only make a 2 second variance in speed as well. Something else I noticed as well was that in the Units section it says that rebuild/reconstruction does not alter the ship's units, however in the Speed section it says that you have to match your speed to guise built, I'm thinking the only ship really effected by this now might be Nagato? Just off the top of my head was it not like 26.5 kts WW1 and 24-25 knots after rebuild?
     
  17. crzyhawk

    crzyhawk Well-Known Member

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    That's a good question HMCS. I've got a few cruisers I am working on and am planning on trying out a few different things. I think a part of it is going to be based on the characteristics of the ships. For example, the Tone I want to build is 35 knots and there aren't many allied ships that can keep up, so I don't think they'll be tempted to follow her. So, I will set her up aggressively with two bow guns angled out 15 degrees either side, which will allow me to attack from either side. Speed will be her defense.

    The Salt Lake City on the other hand is only 32 knots, and is more likely to get chased, thus I plan on dual sterns and a half unit bow gun to keep people honest.

    The Helena at 33 knots I'll probably go with a 75 rounder off either the bow or stern and a 50 rounder pointed the other way since she's faster then most capital ships but slower then many Axis cruisers.

    Which cruiser are you looking at setting up?
     
  18. JasonC

    JasonC Active Member

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    ok im safe on the size of the drag props as my vdt has 1.5" props(made a mistack on my first post). but on the 2 second part means that i need to get new props cause with the props he has the vdt runs at 26 sec and with the draggers on he runs at 36 so thts a 10 sec difference. that means that ill have to get smaller props(damm dont know if i can order em in time)
     
  19. HMCS

    HMCS Active Member

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    The cruiser would be a Cleveland, USS Little Rock.
    Right now she's a virgun BC hull and all the parts minus batteries.Just thinking I need to figure out where the guns are going to go as it will effect equipment placement
    I was half thinking of two bow guns(50rd and 25rd) 15 degrees to each side and a stern gun(50rd). That way I can have offensive weapons to attack but still have a stern gun for defence.
     
  20. HMCS

    HMCS Active Member

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    Jason I'm sure nobody will mind for the first battle. I for one don't care. VDT is going to turn good regardless.