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Tuning FX Impact M3 valve adjuster system upgradation

mubhaur

Member
Nov 8, 2015
1,438
29
Karachi, Pakistan
    Hi,

    I have converted a few M3 valve adjuster system into mk2 valve adjuster system in order to avoid the ugly sound that is created when the front part of valve rod hits the piston pin in the M3 valve adjuster behind which there are two rubber balls.

    But my today's experiments made me believed that as far as design of M3 valve system is concerned, it is much superior to Mk2 system.

    In M3 system FX has combined the benefits of mk1 and mk2.

    In mk1 the valve spring was inside the plenum and only valve travel could be controlled through valve adjuster. But in mk2 the valve spring was between the valve adjuster and the front part of valve pin. No rubber ball was there and as you close the valve, the valve spring gradually goes into the process of coil binding.

    In slug power kit, there was a rubber ball inside the lighter valve spring but that was only for very high power.

    In M3 system, the front part of valve rod strikes the adjuster piston pin before the spring is coil bound fully. That means that the spring might not get fully closed and before that point the front part of valve rod will hit the adjuster pin and as the adjuster piston pin has rubber balls behind it, it absorbs the hit and let us tune the gun in a good manner.

    Now the deal breaker is only the metal to metal contact noise.

    Now I plan to bring the M3 valve adjuster system to its original shape with a modification and that is to reduce the pin length of adjuster piston by 4.5mm and insert a rubber ball of 4.5mm inside the spring. 

    This will make the function of M3 valve adjuster as it should be and there will be no ugly sound of metal to metal contact.

    I hope it will produce better results and consistency. 

    I shall share the results after doing it.

    Bhaur
     
    I've already done something similar. A bunch of folks take a ball out.

    I did a little 3d printed collar (3mm) to keep the stop from moving fore/aft, and left the small ball in the knob. When I screw the end bolt back in, it just touches the small ball. I put the big ball in front of the valve stop similar to the mk2 spk.

    Does quiet the smack down and does seem to shoot fairly consistently. I'm on a 38.9gr .25 NSA tune at 980. Valve around maybe just past where the '5th' line would be. 

    20220226_131129.1645902855.jpg

     
    Hi,

    I have converted a few M3 valve adjuster system into mk2 valve adjuster system in order to avoid the ugly sound that is created when the front part of valve rod hits the piston pin in the M3 valve adjuster behind which there are two rubber balls.

    But my today's experiments made me believed that as far as design of M3 valve system is concerned, it is much superior to Mk2 system.

    In M3 system FX has combined the benefits of mk1 and mk2.

    In mk1 the valve spring was inside the plenum and only valve travel could be controlled through valve adjuster. But in mk2 the valve spring was between the valve adjuster and the front part of valve pin. No rubber ball was there and as you close the valve, the valve spring gradually goes into the process 

    Bhaur

    My early MK2 came with spring in the plenum and rubber ball. 

    Edit* Both my Mk2s are like this (pre power plenum)
     
    Was going to ask can't you just put a rubber ball into place I ordered some from Bengal and Kirkwood spares I believe I got 2 larger ones and 2 smaller ones I used the valve adjuster to knock off 10- 15 after backing off the hammer spring in mk2 it made my gun seem a tad quieter after doing this running about 905 avg with 34 mk2 pellets in 700 mm I may try installing a small ball and adjust it accordingly to keep my tune in the same area rather it hits the ball then go into spring bind 


     

    mubhaur

    Member
    Nov 8, 2015
    1,438
    29
    Karachi, Pakistan
      I've already done something similar. A bunch of folks take a ball out.

      I did a little 3d printed collar (3mm) to keep the stop from moving fore/aft, and left the small ball in the knob. When I screw the end bolt back in, it just touches the small ball. I put the big ball in front of the valve stop similar to the mk2 spk.

      Does quiet the smack down and does seem to shoot fairly consistently. I'm on a 38.9gr .25 NSA tune at 980. Valve around maybe just past where the '5th' line would be. 

      20220226_131129.1645902855.jpg

      Yes another way to skin a cat.

      I hope you get good consistency, better control through valve adjuster and no "tung" ugly noise.

      Bhaur
       
      Can someone elaborate on the following difference:

      - reducing v0 by 30FPS using HST,

      - reducing v0 by 30FPS using valve return know.

      How can it influence accuracy?

      Good question but it seems to make a difference I don't know why or how maybe it shuts the valve faster causing less turbulence again I'm just guessing hopefully some one can tell us why and or how 
       

      mubhaur

      Member
      Nov 8, 2015
      1,438
      29
      Karachi, Pakistan
        Can someone elaborate on the following difference:

        - reducing v0 by 30FPS using HST,

        - reducing v0 by 30FPS using valve return know.

        How can it influence accuracy?

        There are a lot of combinations of reg, hst and valve adjuster to achieve the same fps.

        To me with various projectiles in order to achieve best tune for best accuracy, I have to test all possible combinations.

        For decreasing 30 fps it is possible that hst may increase or degrade accuracy. Similar is the case with valve adjuster. 

        Sometimes a bit of adjustment with hst and a bit with valve.

        So it's all subjective to me and depends that what kind of airflow favours a certain projectile.

        To me its always try and test every combination till achieve the best one.

        Bhaur
         

        bigHUN

        Member
        Jan 16, 2020
        1,820
        39
        Canada
          Can someone elaborate on the following difference:

          - reducing v0 by 30FPS using HST,

          - reducing v0 by 30FPS using valve return know.

          How can it influence accuracy?

          The difference is actually a {hammer spring recovery between max and min as morphing} versus {stopping the C1 at certain distance}.

          With hammer spring adjustment (only) the C1 can travel +/- let say 0.1 or 0.2 or 0.5 (depend of certain specific factors) and that results a more or less air volume and pressure...

          but with valve spring adjustment you can lock=stop the C1 at zero meaning trying to give a same air volume and pressure.

          C1 travel actually translates to valve poppet - dwell time.

          Edit:

          sorry I just realized you talking about M3 (and me sampled the MK2), but this shall apply there as well.
           

          douger

          Member
          Apr 1, 2016
          4,291
          109
          55
          montgomery illinois
            iv played with the m3 also I shortened the metal piston by 1/4 of its lenght that the c-1 hits and seems way better adjustments, also you dont have to go out to say line 5-6 ? better control on the valve with 1 rubber ball also not so stiff. but everyone shooting different powers im just slinging 18 gr at 900-920 use rubber ball i played with alsi=o instead of the pin thing
             
            Last edited:

            Vetmx

            Member
            Dec 4, 2017
            3,158
            117
            Pa, United States
              I guess you could make the piston in the knob out of delrin. It would be more forgiving than the metal piston. I personally don’t have any issues with the stock setup. I only use the stock springs in my M3’s. I also take most of the stress off the system by reducing my hammer strike with my wheel down to where I can control my dwell with spring only. Very little stress on the rubber balls because they are maybe only getting lightly tapped by the C1. The internet full blast Impact tunes or ballpoint pen springs that come in power kits will wreak havoc on those poor little rubber balls.
               
              I’m clearly missing the why in this thread. Can someone explain the basics to me. Is this just about the tinking sound and slightly more efficient tune or is this really an issue of destruction of the impact internals? If so how many shots are we talking about before I need to worry about it. I’m obviously not a major tinkering shooter but I read these tune threads looking for essential tunes