Upgrade and Repair Tips

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Upgrade and Repair Tips

Post by Moondog »

Gearbox Upgrade and Repair Tips
by Moondog

Taking apart your AEG and opening up your gearbox is a very daunting for those who've never done it. You're afraid you'll screw up your AEG or break something. But at some point your AEG may need repair or you want to upgrade the spring or you just want to relube and maintain it.
You'll find step-by-step video guides in the links below.

Tip #1 Don't Do It
Dont' upgrade your gearbox. Almost all performance upgrades you do to your gearbox will decrease it's reliability and lead you to a cascading series of further tweeks and repairs. There I said it. Many of you will desregard this and read further. Good luck and don't say I didn't warn you.

Read Up
Take a few hours or days to read up on your AEG. You will also find videos on YouTube by various folks working on their AEGs. There are various sites (listed below). Be sure to learn is how to re-assemble your AEG. It's not fixed if you can't put it back together.

Get the right tools for the job. You'll need a good set of screw drivers (smaller jewler type) and a hex/allen set. A good set of locking pliers, needle nose pliers, wire cutters and clamps are helpful. Also have a Dremil or metal file handy just in case you need to make a 'modificaiton'. If you need to rewire, you may also need a soldering iron.

You should also have a secure place to hold the various screws, springs and small parts that you will be taking off your AEG. It's very easy to lose track of some small but vital part on a work table or a floor. You can use a motor to magnetically pick up any metal parts that may have gotten lost on the floor or carpet.

Be sure you research what parts you will need to make a repair, replacement or upgrade. Nothing is more frustrating than getting your gearbox open and then finding out a part doesn't fit right or is the wrong model. It never hurts to buy some spare shims and bushings. Pick up a variety set of O-rings from a hardware or plumbing store (sizes 12-16 will do).

You should buy 100% silicone spray lube and silicone grease. Be sure it's fit for airsoft parts and safe for silicone and rubber. Never use WD-40 or Liquid Wrench. White Lithium grease is often used for airsoft gears because it's hi-temperature lube but I don't like it becasue if it degrades the o-ring and hop-up bucking and tends to dry up after a few months. Instead I use bicycle Teflon impregnated silicone grease.

Silicone Spray Lube
http://store.matrixbb.com/servlet/-strs ... HFC/Detail

Guarder Teflon Grease
http://store.matrixbb.com/servlet/-strs ... ase/Detail

Tri-Flo Teflon Grease
http://www.performancebike.com/shop/pro ... ry_ID=4213

Finish Line Teflon Grease
http://www.amazon.com/Finish-Line-Teflo ... nturesinA/

Take Your Time
Be patient. The first time I opened up my gearbox to just change the spring, it took me a good half day. There's a lot of little parts so take notes as to what they are and where they go. Make drawings or take photos of each part before you take it out so you know where it goes when you reassemble it. Some parts like the trigger and anti-reversal latch are tricky to keep in place while you put things back together. You'll get the hang of it eventually.

Like a car, you really should perform scheduled check-ups and maintanace if you want to keep it running for years. You'll want to clean and relube all the moving parts. You'll want to clean out carbon gunk from the electrical contacts. And you'll want to inspect all the parts for wear and tear and replace as needed before they fail. As a rule of thumb get it checked every 25,000 rds or so.


Great website that offers step-by-step videos on various AEG's and gearboxes along with technical guides.

http://www.airsoftretreat.com/reviews/s ... =67&cat=49
A good general guide to the Version 2 gearbox (which is also mostly applicable for the Version 3) Also posted on Airsplat

Airsplat offers online versions of many popular AEG owners manuals. Some info on dismantling AEGs.

All Chines Made (ACM). A message board devoted to Clones and their modifications. Based in the Philippines, these guys realy know how to tweek. Be advised some of the posts are in Filipino (Tagalog). But everybody in the Phlippines speaks english so if you post a request to repeat a post in in English (nicely) they will usually comply.

Daedalus Development Group. An airsmith with guides on M4s and G36 gearboxes projects and walk throughs.

An airsoft mad scientist who like to push the limits of his various AEGs in ways few would want to replicate.

http://www.airsoftmechanics.com/home/co ... ory/13/30/
Air Tech discussions on various upgrade modifications

Animation of How A Gearbox Works
Created by Bolduerbum
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