Modifying the tappet plate for better air seal

[Skladfin]

well, just to summarize, here are the main ideas of this mod:

-Better airseal
-Easily doable(sanding 0.5mm off plastic isnt hard)
-Free
-No theoritical damage could happen to any other mechbox parts
-If tappet plate goes boom, easily replaceable($10 avg).
-No need to custom machine anything.
-Here is a quote from an Arnies member:

of course, but then you may in some cases get a nozzle that doesn't get retracted far enough by the sector gear, thereby preventing BBs from feeding past the front of the nozzle. The OP's method doesn't cause the nozzle to sit further forward when fully retracted by the sector gear.

Not to mention the challenge of finding the correctly just-a-little-longer nozzle.

Shaving material off the gearbox is harder, non-reverseable, and expensive/hard to replace if any problem occurs.

If someone wants to test the mod out for me that'd be great. Currently Im out of AEGs.

[Azathoth]

I have 3 gearbox shells coming to me. when i'll take a look at doing this for a project build.

[Skladfin]

so apparently someone over at arnies did try this and it worked! given him over 150FPS boost(Note, he had horrid airseal to begin with).

Done it to my M14, as I was getting loads of [lost air] up to 150fps in 1 case sanded 1mm off the front of the tappet plate re installed it, tested it and gained all the fps back plus a little extra.

On closer inspection and comparison of the hop rubbers on my barrel out of my SOC16 against the M14 revealed the sealing lip was a nats doodah shorter on 1 than the other, 1 is a Guarder black, the other origin unknown (believed TM).

nice, new mod.

[Con Murder]

Goona save this link, airseal problems have been like a looming nightmare for me! Never had a problem yet but always worried that with so many components not originating from the same creator as the original the ugly loss was goona show.

Nice simple and cheap, me likes

[coach]

cool. wanna make me a few? I am pretty sure I have a couple air leak issues. lol

I should chrony with .2's first though. :|

[G26]

Shaving tappet plate is the way to go. It isn't new, it's been in practice for quite a while. On how much to shave, well it depends on individual setups. Have to go by trial and error (measure twice, shave once).

A very simple method to see if this will help you gain FPS, is to chamber a few rounds when the AEG is upsidedown. Then shoot on semi. If the BBs jumps out, congrats, you just found your airleak source.

But merely shaving the tappet plate isn't enough. At times (mostly ACM GB), it's the part where it engages the sector chip that is preventing it fully return (max seal). So experiment with both ends so that the ASN will protude more into the hopup chamber giving a much better seal.

Using a longer ASN and shaving the hopup chamber where it meets with the GB will not work and it will only create misfeeds.

A good candidate for this mod is Guarder's tappet plate. They're more durable to begin with.

[Skladfin]

I just tried this personally on a client's gun

gained back 45 ish FPS.

The trick is to do the flashlight-under-hop-up-unit trick to keep checking whether the nozzle fully meets the hop up rubber or not. I think someone on here had a picture explaining how to do this neat little trick.

[Skruface]

Has anyone tried crater-cutting the rear of the nozzle and adding an o-ring?

http://filakairsoft.30.forumer.com/i...?showtopic=908

[yuhaoyang]

Nope... I would assume you need a lathe. I don't think hand held devices would be precise enough.

[XtenZ]

Skladfin,

I'd be willing for you to try this on my SCAR, paying for the service of course. It needs a lil GunDoc love anyways. I guess this is assuming there is a replacment tappet available in case it does break.

Let me know sir.

[Skladfin]

Originally Posted by XtenZ

Skladfin,

I'd be willing for you to try this on my SCAR, paying for the service of course. It needs a lil GunDoc love anyways. I guess this is assuming there is a replacment tappet available in case it does break.

Let me know sir.

for sure, PMed

[locprecision]

Hi guys, this is my first post here at ASC. I've read this trick being done several months ago on ACM games. It does work! Using a pair of dial verniers, I checked the tappet plate thickness first which was .105". I then carefully sanded the front end taking off .020". I used the dial verniers to make sure that I was sanding the end square. On a jg G36c, I gained about 30fps.. The important thing is not to take to much off and getting it square. This particular tappet plate has cycled well over 10,000 rds. and still going strong.

[Schlyder]

I think my fps is a little lower than it should be, on one gun for sure. I suspect it is an air seal issue. I did the upside down test, and I had jumpers, so if that is a sign of an air leak, then my seal issue is confirmed. I will try this mod next time I have to open up that mechbox. Thanks for the info lads.

[incrediboy729]

I very well might try this on my 500+fps CA m4. I'll let you know what happens if i try
I'm curious to see how much this would help on a high FPS setup

[Skladfin]

Sorry guys, but i think there's a little bit of misunderstanding here. You won't gain any more FPS if the Airseal nozzle is already making contact with the Hop up rubber.

Also, the "jumper BB" method of checking for air leak is inaccurate. BBs can jump because the nozzle is moving at a high speed and hitting the BBs in the feed tube. This happens in guns with perfect seal as well.

The only accurate way to check for an airleak is by flashing a light from the feed tube while you have the hop up unit mating perfectly with the gearbox(The Air nozzle has to be at its FURTHEST position). Look down the barrel and see if you see any ring of light(or part of a ring). If there is, the nozzle is not reaching the rubber. If you see no light, there is no need for you to mill the tappet plate.

I hope this can clear up some confusion.