In this Mechbox Monday, we look at the basic toolkit and items you should have on hand before attempting to upgrade, repair or modify your airsoft gun.

This guide is primarily focused on the basic toolkit needed for beginning work on your AEG. Some specialized tools may be required for pistols and other airsoft guns.

Tools:

Most of you should be able to find the basic tools in your home, dorm, garage, shop or borrow them from a friend. Below is a list of the tools we recommend before starting any airsoft (AEG) work:

1. Screwdrivers (assorted slotted and phillips)
2. Allen/hex wrenches (metric)
3. Hook and pick tools
4. Needle-nose pliers (snipe-nose pliers)

Screwdrivers are fairly obvious, but these will help in disassembling the body and the internal components of the mechbox.

Allen or hex wrenches are essential for disassembling some AEGs and for adjusting motors. (Be sure the kit you buy has a 1.5mm Allen wrench).

Torx drivers are more specific to the Tokyo Marui (TM) mechbox, be sure to have a T10 torx driver if you’re opening TM mechboxes.

Hook and pick tools are really great to have for all kinds of situations. We regularly use the picks for releasing the anti-reversal latch, removing small parts, etc.

Needle-nose pliers are great for holding small parts in place or reattaching springs.

Miscellaneous:

Every job may require something specialized, but the general airsoft toolkit should also include the following:

1. Silicon lube (various weights)
2. Lube gel
3. White lithium grease
4. Multi-tool/knife

Silicon lubricants can be purchased locally at many hobby shops or online from most airsoft retailers. Make sure that you get 100% silicon, other oils can have adverse reactions with certain rubber components in airsoft guns. Silicon lubricants come in different weights (viscosities) for many uses including cleaning barrels, lubricating pistol slides and general magazine maintenance.

Lube gel is a great substance for lubricating the inner wall of the cylinder, tappet plate rails, air nozzle and the seals of the piston head. We also use lube gel to hold parts in place (like the head of a small screw). Superlube and Radio Shack lube gel are great alternatives to the Systema cylinder grease.

White lithium grease is a great lube for AEG gears, bushings and shims. You can find lithium grease in spray or tube, I recommend the tube form as it’s much easier to apply (spray lithium is really too thin and messy to be effective). Systema and others sell airsoft specific gear greases, we can’t find any obvious reason to pay more for them.

Multi-tools come in very handy and sometimes have just the right blade or other tool you’ll need when your mechbox is wide open and realize you don’t have the right size tip on your screwdrivers. Many times we have resorted to the Leatherman or Gerber multi-tool to get us out of tight spot during open-mechbox surgery. You’ll be glad you bought one anyway, if you haven’t already.

In closing:

There are plenty more tips that didn’t make it into this “essentials” list. Some other great things to have around are storage bins, even old jars or bowls to sort your parts as they are removed. Anything you can do to keep yourself organized will seriously contribute to a less stressful repair and reduce the chances of losing small parts. Stay tuned for more in-depth articles in the future including a list of spare parts we recommend you keep on hand.

Image used in header by: Schiller Garcia

Modifying an AEG can provide some much needed performance improvements, but what does this do for the life of your airsoft gun?

I’ve been told that just by opening a mechbox the chance that something goes wrong goes up exponentially. Why is this? Can I do anything to change that?

 

The short answer is, not necessarily. 

In fact, many times with the cheaper Chinese AEGs I have seen significant improvements to reliability after opening and upgrading the mechbox. Obviously, not all upgrades go as smoothly as expected and there is always a chance you’ll have to open it five more times to get it right. That does happen, even for someone that has performed the exact same upgrade hundreds of times before without a single problem.

Keep it simple. More is less, most of the time.

Some people have a tendency to want to replace everything inside the mechbox believing it will magically create the perfect weapon. In most cases, the more you add, the more likely you are to create new points of failure. The large number of manufacturers today who produce airsoft mechbox components also adds to the complexity of choosing parts that work well together. So, especially for people new to upgrading, I highly recommend starting with the basics (spring and bushings). More does not always equal better.

 

What, if anything, do I have to upgrade in my mechbox to support an M120 spring?

 

In my opinion, the following is required: 

1. Metal bushings.
2. Reinforced (higher quality) gears.

The most likely failure point with a stronger spring will be the gears or the piston. A wobbly gear (due to a loose bearing) can lead to stripping of the gears. The safe bet is to add the bearings and a set of new gears. Not all gears are created equal. Ideally, buy gears and bushings from a reputable manufacturer such as Systema, Guarder or Prometheus.

For improved performance: 

1. Ball bearing spring guide.
2. New piston and ball bearing piston head.
3. Consider a more powerful battery.

The ball bearing guide and head will allow the spring to rotate smoothly as it compresses and decompresses. A smooth rotation will reduce binding and twisting, giving the mechbox a slightly better ROF (rate of fire) and better durability. You might get a little more life out of the mechbox by adding a new piston. The fresh grooves on the piston will to mesh up with your new gears, again reducing the chance of premature failure after an upgrade. For most AEGs, the M120 will definitely slow the ROF and decrease overall battery life, so a slight increase in battery mAh or voltage may be necessary.

The key is to realize that everything is connected, so what starts out as a “simple” 400FPS (feet per second) upgrade can quickly become an expensive chore of adding more parts than originally planned. As stated in the first question, simple is usually better and more reliable. Something to consider before planning your upgrade.

Note: The M120 is usually fine for most mechbox designs, however the V2 box has some weak spots. Don’t be surprised if a fracture develops at the front of a V2 mechbox. There are some ways to prevent that, but I’ll save that for a future article.

This week’s question involves thread diameter and fitting a silencer to your airsoft gun. So, which way am I supposed to turn this thing anyway?

What size are the flash hider threads on Tokyo Maruis? I’m looking to make my own mock silencer, but I don’t know what size tapping bit I need to buy.

 

 

Most AEGs have a 14mm x 1mm (fine pitch) thread with either a clockwise or anti-clockwise rotation or pitch to the threads. So, it will either screw on using a righty tighty, lefty loosy method (which is clockwise/positive) or it screws to the left to tighten (anti-clockwise/negative). 

Each manufacturer has its own idea about whether to use clockwise or anti-clockwise, but I feel we can safely say that MOST AEGs use an anti-clockwise or negative 14mm thread. Tokyo Marui definitely uses the negative, anti-clockwise thread on its AEGs. In contrast, some guns have non-standard thread sizes like the TM SOCOM Mk23 pistol which uses a 16mm positive thread.

 

Just an FYI for those of you in the USA.

Technically speaking some imitation suppressors are subject to “legal issues” with regards to USA BATFE rules. I have ever experienced any issues with the use of an airsoft suppressor, but if you’re doing something stupid with an airsoft gun and it has a suppressor on it… you could be looking at some additional legal problems. This applies to homemade “silencers” as well.

There are many factors to take into consideration when comparing the final FPS (feet per second) results of airsoft upgrade springs.  Every component inside a mechbox will contribute to the final performance of any spring upgrade.

It’s virtually impossible to test every variation of spring, piston, nozzle, cylinder and barrel configuration for all the makes, models and types of AEGs on the market today. With that preface in mind, the following chart is designed to illustrate “approximate” target FPS of a few popular spring manufacturers.

Above
Chart illustrates target FPS and corresponding springs that will come close to or under the target FPS depending on the specific AEG.

Notes
Always consider upgrading your gears, bushings and mechbox case when adding higher performance springs to your AEG.  When upgrading to 450FPS or more it is advisable to add higher quality gears, torque motor/gears and reinforced mechbox cases. The added strain on the motor may also reduce the performance of the battery. So, before upgrading a M4 with a mini battery to 450FPS – it would be wise to look at large battery conversion/options.

Future tests
Our longer term goal is to build a library of very specific upgrades with detailed parts lists to test real world performance results.  For example, we’ll open a new G36C in stock configuration and get an average FPS and relative ROF (rate of fire) measurement.  We’ll then upgrade the spring and bushings, retest the average FPS/ROF and publish the results.  We believe this catalog of specific upgrades will be infinitely more useful than a generic guesstimate spring comparison chart…it’s just going to take a while to develop!

The old charts
In response to some questions about the new chart, I’ve made the previous version available as a PDF download. -6mm

Download the old airsoft spring comparison chart. (308kb/PDF)

For those new to airsoft, the mechbox is often a source of mystery. Mechbox is airsoft slang for “mechanical box” or the gearbox case that houses the gears, springs, piston and cylinder which powers an AEG. The mechbox or airsoft gearbox is essentially a small electric-powered air compressor. This article will give you an inside look at the mechbox and how everything works.

Mechbox animation

We’ve created a version 2 gearbox and animated it to demonstrate how the internal components work together to create the power inside an airsoft electric gun.