Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

G36C - Shims etc.

Options
  • 22-09-2008 10:51am
    #1
    MacAonghusa
    Registered Users Posts: 954 ✭✭✭


    I just upgraded my JG G36C at the w'end. I added metal bushings, spring guide, piston & shims but have some problems:

    Question 1:     how do you know how much shims to use?
    Following an online vid (thx Tig) I just added enough so that the gears would turn by hand easily and nothing felt to loose/tight. After I had assembled it I found 3 shims which had fallen out during disassembly. So I now have 1 shim in where there previously seemed to be 4. Anyone advice on what i should have in there? Could it be that you don't need as many shims with metal bushings (instead of the PC ones)?

    Question 2: My FPS is now at around 290 :(
    What could the problem be? Not enough lube on the gears? Too tight busings? Air leak? Any other reason?


Comments

  • Options
    #2
    Tigger
    Closed Accounts Posts: 16,705 ✭✭✭✭Tigger


    MacAonghusa wrote: »
    I just upgraded my JG G36C at the w'end. I added metal bushings, spring guide, piston & shims but have some problems:

    Question 1:     how do you know how much shims to use?
    Following an online vid (thx Tig) I just added enough so that the gears would turn by hand easily and nothing felt to loose/tight. After I had assembled it I found 3 shims which had fallen out during disassembly. So I now have 1 shim in where there previously seemed to be 4. Anyone advice on what i should have in there? Could it be that you don't need as many shims with metal

    bushings (instead of the PC ones)?

    are you using bearing bushings?
    did tey click home fully

    yes you will need a different number of shims
    mabey more mabey less
    fps isn't affected by greas on gears or by tight box (oeer) but by the spring the cylinder the piston the hop seal etc did you grease the o ring on the piston head
    did you change the spring or the hop
    a common issue on g36s's is getting a wire caught between the gearboz nozzel and the hop unit
    stops tem mating propperly




    Question 2: My FPS is now at around 290 :(
    What could the problem be? Not enough lube on the gears? Too tight busings? Air leak? Any other reason?

    btw there was nothing wrong with the old piston


  • Options
    #3
    MacAonghusa
    Registered Users Posts: 954 ✭✭✭MacAonghusa


    Tigger wrote: »
    are you using bearing bushings?
    No, just ordinary ones, they seems to click into place fine.
    Tigger wrote: »
    yes you will need a different number of shims
    mabey more mabey less

    The only one I have now is behind the sector gear. Gears seem fine when moved by hand.
    Tigger wrote: »
    fps isn't affected by greas on gears or by tight box (oeer) but by the spring the cylinder the piston the hop seal etc did you grease the o ring on the piston head

    :D
    Changed the hop previously.
    Greased the o-ring, think I put cylinder grease on it. Had to modify the piston slightly (put a small hole in it) to get the head to mate properly.
    Spring is the same.
    Tigger wrote: »
    a common issue on g36s's is getting a wire caught between the gearboz nozzel and the hop unit
    stops tem mating propperly

    I moved the hop fwd when putting back in the mech box. Will check again there is nothing interfering.
    Tigger wrote: »
    btw there was nothing wrong with the old piston

    Yeah, but I was hoping i'd get a few extra fps cos it was shooting low enough.


  • Options
    #4
    kevteljeur
    Registered Users Posts: 1,287 ✭✭✭kevteljeur


    Maybe it's a case of taking it apart and doing it again, and seeing if maybe you need those shims after all. The output drop could be a number of things and I'm far from qualified to list them but I understand that the o-ring is greased with silicone grease, while other moving parts with LM/Moly grease (which isn't nearly as sticky). If you use silicone grease on the piston guides, you'll slow it down. And just too much grease could slow it down, I recall Motosam describing lowering his power output by smothering his piston guides with grease. Not good.

    Make sure the spring is seated correctly within the piston and if worst comes to worst, you could add spacers to the base of the spring to compress it more. Adding less than 1mm in a G36C significantly increases apparent spring power.

    (Yes, I struggled with some of these things when I took my G36C mechbox apart to fiddle with it - still, a great learning experience!)


  • Options
    #5
    MacAonghusa
    Registered Users Posts: 954 ✭✭✭MacAonghusa


    kevteljeur wrote: »
    Maybe it's a case of taking it apart and doing it again, and seeing if maybe you need those shims after all. The output drop could be a number of things and I'm far from qualified to list them but I understand that the o-ring is greased with silicone grease, while other moving parts with LM/Moly grease (which isn't nearly as sticky). If you use silicone grease on the piston guides, you'll slow it down. And just too much grease could slow it down, I recall Motosam describing lowering his power output by smothering his piston guides with grease. Not good.

    Off the top of my head I think i used cylinder grease on the o-ring which is lighter than gear grease but i'll probably strip it again and check all these things.
    I put gear grease on the piston guides ... might need to go at that again.
    kevteljeur wrote: »
    Make sure the spring is seated correctly within the piston
    It just sits into place on the JG, there's nothing to locate or anything.

    The grease i'm using is the G&P Grease set from AirsoftEire.

    kevteljeur wrote: »
    still, a great learning experience!)

    It is. Though potentially an expensive one :)


  • Options
    #6
    theburi
    Registered Users Posts: 163 ✭✭theburi


    don't worry about power output. It can be solved by getting higher spring.
    with my JG36C I had to get m90 spring to get it 0.95J.
    Aparently JG piston forms good seal. So what may be the case is that you've got new cyclinder and it is not that good in forming air seal.
    Make sure that power measure is consistent and than upgrate a spring.

    PS Right Lubricant (O-ring) will make a difference.
    PS. different make M100 springs will result in different power output.


  • Advertisement
  • Options
    #7
    MacAonghusa
    Registered Users Posts: 954 ✭✭✭MacAonghusa


    theburi wrote: »
    don't worry about power output. It can be solved by getting higher spring.
    with my JG36C I had to get m90 spring to get it 0.95J.
    Aparently JG piston forms good seal. So what may be the case is that you've got new cyclinder and it is not that good in forming air seal.
    Make sure that power measure is consistent and than upgrate a spring.

    PS Right Lubricant (O-ring) will make a difference.
    PS. different make M100 springs will result in different power output.

    The cylinder & piston head are the same so there shouldn't be a problem there.
    I did notice some inconsistency in the output so i'll take a LOT more shots after I disassy/reassy here.


Advertisement