DKM Tirpitz Refit

Discussion in 'Warship Builds' started by JustinScott, Mar 23, 2008.

  1. JustinScott

    JustinScott Well-Known Member

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    Right. I understand that. What I don't understand is when both solenoids open at the same time, shouldn't the same effect happen?

    What I mean is the pressure should bleed through the open valves and reduce pressure on the second cannon anyway.

    I get that people say it works, but why? My only guess is that the valves act as a air flow restrictor which slows the pressure drop. In that case, the" one way valve" make sense too; as they would also add resistance.
     
  2. Beaver

    Beaver 2020 Rookie of the Year Admiral (Supporter)

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    With two solenoids you also run two supply hoses from the regulator. That means that any pressure drop from one solenoid would run back through the regulator before it could affect the other cannon. The regulator will eat the pressure drop. Also putting in check valve with prevent gas robbing as well. Put them inline as close to the regulator as you can.
     
  3. GregMcFadden

    GregMcFadden Facilitator RCWC Staff

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    Those cannons need one solenoid per barrel. You also need to check piston height setting and replace the o rings in pairs
     
  4. jadfer

    jadfer Well-Known Member

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    Hey Justin!

    Question are you using 1 solenoid to run two guns? If so then Beaver is right, run 2 solenoids.. 1 per gun.

    If you are getting a delay firing then it might be a supply issue. It is most likely related to voltage or PSI.

    Are you running a dual air system? 150PSI for guns and 100 psi for triggers?

    I noticed they are 12V solenoids.. they usually need at least 9.9v of power to be fast enough... what voltage are you supplying?

    If you are pushing 150PSI through the solenoid (rated at 100psi as a guess .. the page didn't show a max pressure)... then it will be harder to push the piston down ... without the proper voltage.

    I had similar issues with Kips in the past when the polyurethane seals went bad... 6v was not enough to get the valves to open normally.. changing the piston to Viton had less adhesion to the bottom of the valve and allowed it to operate as intended.

    Check the voltage / psi.. that may be the culprit. I use parker 1/4 hose and 1/16 from solenoid to guns and NEVER needed a check valve or accumulator tank with dual sterns or any single gun, however I use a palmer regulator with two feeds so the duals guns would each be on a separate feed from the regulator. SHHHHHH don't tell anyone.. most people think palmer regulators don't work.. lets keep it that way.. :)
     
    Last edited: May 26, 2017
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  5. buttsakauf

    buttsakauf Well-Known Member

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    Palmer's?! No one uses those. Cough cough...
     

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    Last edited: May 26, 2017
  6. jadfer

    jadfer Well-Known Member

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    SHHHHHHHH
     
  7. JustinScott

    JustinScott Well-Known Member

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    Thank guys.

    I'm running a 12V battery, with 12V solid state electronic fire control boards, running the electronic valves at 12V.
     
  8. jadfer

    jadfer Well-Known Member

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    Try reducing the pressure and see how that affects it.
     
  9. JustinScott

    JustinScott Well-Known Member

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    From the battle a few weeks ago, the Tirpitz's motor destroyed its gearbox twice. Here is a picture of the damaged gears.

    Off to Amazon...
     

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  10. Kevin P.

    Kevin P. Well-Known Member

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    32 pitch is where it's at. I get pinions on amazon and the larger gear from stock drive products, pricey but should outlast the life of several ships

    http://www.sdp-si.com/
     
  11. thegeek

    thegeek Well-Known Member

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    Ebay for me. 5 mm is very near 3/16 so you can get away with metric (the better system).
    I use 3/16 music wire for shafts.
    Easy to silver solder or braise.
     
  12. JustinScott

    JustinScott Well-Known Member

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    Unfortunately my motor has a 4mm shaft. So I bought a 1/8" (3.175mm) pinion with the plan of drilling it.

    But yes I've gone to 32pitch hardened steel.
     
  13. JustinScott

    JustinScott Well-Known Member

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    Ok. Opened up the radio today. Found that I had rewired it at some point in the past! I barely remember some of it, maybe 15 years ago. My god has it been that long?

    The elevator channel has been rewired and so have the gear/aux.
     

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  14. JustinScott

    JustinScott Well-Known Member

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    The first thing I have wanted to do is take rarena's suggestion of giving the throttle at 'center'. This I did by pulling apart the joysticks and using the spring mechanism from the aileron.
     

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  15. JustinScott

    JustinScott Well-Known Member

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    Next step, repair the gear & aux channel by re-wiring them back to their switches.
     

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  16. JustinScott

    JustinScott Well-Known Member

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    Now time for the gun triggers. First I needed single throw push buttons; which are surprisingly hard to find now that Radio Shack is out of business.

    Then I needed a plastic structure to hold the triggers in the radio. After a trip to Home Depot, I settled on the carving up a lid from a clearance storage tote.
     

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  17. JustinScott

    JustinScott Well-Known Member

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    Next I pulled out my oscope and measured how the joysticks worked. 5V full throw across a 3kOhm potentiometer with 2.5V being center servo.

    I settled on two 1.5k ohm resistors going across each of my pushbuttons. This setup gives my stock center position (and current) but not full throw. This is OK with me, I can compensate on the firing board. At least I'm not getting any servo jitter or glitches.
     

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  18. JustinScott

    JustinScott Well-Known Member

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