Custom Version 7 Steel Spur Gear

In the quest for more FPS out of the Version 7 gearbox/mechbox, I took the challenge and got a functioning
sniper set-up out of my former stocker Tokyo Marui M14.

One of the problems that face Tokyo Marui M14 AEG owners when upgrading (to stronger springs) are the getting the proper gearsets for the version 7 gearbox.

The V.7 gearbox uses standard Sector and Bevel gear but it uses a "smaller" spur gear. GNP did produce the
so called "Super Torque Up" steel spur gear but upon close inspection it still has the "stock" number of teeth
but it's made of steel which is a stronger material compared to the stock spur gear (which is casted form a
weak alloy).

 

  Though the GNP spur gear is enough to do the job to pull heavier springs (did i hear SP150?)... I wasn't satisfied because it is a bit thin compared to the Systema STU gears that it's suppose to mesh with.What i did was.... got a spur gear machine fabricated (out of tool steel) having the specs of the GNP spur gear, but having the thickness of a Systema one... When i got it spinning smoothly with the Sector and Bevel gear...

What i did was get it "tempered" to make the material harder.... Still not sure how long will this fabricated steel spur gear would last since i was only able to field the rifle once since the installation... Anyway will just put updates on it's performance or it's lifespan....

Update January 29, 2007

       The Rifle is used on a regular basis (weekend skirmishes) and so far the performance is still impressive. The fabricated spur gear is still cranking the SP150 spring without a problem and the whole mechbox/gearbox still sounds a lot like a stock unit (will do a more detailed article about the whole internal set-up of the Tokyo Marui M14 when i find the time). And I still yet to get my hands on a chronometer so that I could put some actual FPS readings with this set-up. So until I get all those work done, this will have to do for now.

 Update May 15, 2007

      Opened up the gearbox/mechbox of the project gun (Tokyo Marui M14 Rifle Airsoft Gun)  for some relubrication and to check the internals for wear and tear. The bore and piston head o-ring needs some regreasing with silicon base grease. Upon close inspection i noticed some wear on the fabricated spur gear's axle and with the axle worn-out, play occured on the hole of the metal bushing causing it to wear out of shape. I didn't have time to fix it properly( as it will include some precision drilling on the center of the spur gear and fitting in a new axle from a donor spur gear)  as i still have an airsoft game the following day. So what i did was do a temporary fix, replaced the worn-out metal bushing with a new one (which will be surely be damaged until the proper fix is done) relubed the gear sets and reshimmed them and hope that they will hold out till i get the time to give them a proper fix. Anyway the spring have shortened a bit due to heavy usage. Will update once i redo the fix.