AEG part correspondance and Tech Info

[tZ]

I wrote these up... its part of a series if anyone could tell me of any missperfections in the data that would be deleightfull. ;D


AEG Part Correspondence

By: Todd Zmijewski

Disclaimer: The issues discussed and addressed below are done so on a theoretical basis. I take no responsibility for the misunderstanding of this guide and its negative affect on your AEG.

General: This guide will discuss in depth AEG (automatic electric gun) gearbox part correspondence. The gearbox types being addressed are version one to six.

• Recent innovations have prompted the production of a new bread of automatic electric gun. The information presented in this guide does not correspond to these guns (i.e. Systema PTW series, etc).

• The information presented below corresponds to most Tokyo Marui, Classic Army and ICS AEG internals. All manufactures listed are listed on a reference and example basis only.

• One should link the appropriateness of their AEG gearbox version with the information above before proceeding.

Audience Focus

The target audience of this guide is the beginning to intermediate viewer. The viewer should have basic articulation knowledge and be familiar with AEG gearbox vocabulary (piston, piston head, spring, etc).

Information Addressed

General information regarding individual part make up in an AEG gearbox will be expanded upon in terms of type, material and other qualities appropriate per discussion. Understanding the aesthetic qualities in coherence with the physical components of each part is the main focus.

Goal

Understanding the interaction and working of the individual parts in a gearbox as a whole. The ability to articulate proper means of replacement per circumstance or upgrade is the overall goal (what type of part, what parts, etc).

Bushings/Bearings

Bushings/Bearings: The parts (6) that hold the gears in place inside an Automatic Electric Gun gearbox.

Stock bushings vary amongst manufacture. However, generally there are two types of bushings.

Nylon(plastic)
Metal

Brand(s) w/ Plastic Stock Bushings

ICS
Tokyo Marui

Brand(s) w/ Metal Stock Bushing/bearings

Classic Army
G & G
G & P
Airsoft Elite
Systema

Above all else, the bushings in an AEG must be metal before considering any other upgrade option (spring, cylinder, etc).

Reasoning

In contrast to metal nylon is mush more susceptible to wear and flex. On the whole, guns with metal bushings will be more durable, reliable, gears will rotate smoother, and the over all lifespan of the gun will be drastically increased.

However, a gun remaining stock can still run for a significant amount of time before the nylon bushings must be replaced, but it is recommended they be replaced.

Once a velocity boost is considered the nylon bushings must be replaced with metal ones.

(i.e. Since, Classic Army Automatic Electric guns come stock with metal bushings there would be no need to replace them. In contrast to Tokyo Marui were the nylon bushings would need to be replaced with metal ones before considering any other enhancement option(s).)

Bushing vs. Bearing

One must determine whether bearings or bushings are a better upgrade option when replacing stock nylon ones.

Definition

Bushing: A fixed removable cylindrical metal lining used to constrain, guide and reduce friction

Bearing: A device that supports guides and reduces the friction of motion between fixed moving machine parts.

Contrast

A bushing is a non moving guide that contains a fixed hole. Similarly, a bearing is bushing that contains a movable ball bearing inside. This ball bearing moves in conjunction with the axle it supports and guides (i.e. gear axle). The movement of the support in conjunction with the axle on a bearing lowers friction better maintaining a higher rate of fire then a bushing.

Bearings should not be used with any gun velocity over 350 fps. Bushings are free to be used in conjunction with any spring velocity.

Diameter

Most Tokyo Marui, ICS and Airsoft Elite automatic electric guns have 6mm bushing holes in the gearbox. However, some manufactures such as; classic army produce AEGs with 7mm or 8mm bushing holes in the gearbox. Before purchasing bearings or bushings one must research which diameter is appropriate for their gearbox.

6mm, 7mm and 8mm bushings can not be used in conjunction with the same gearbox (i.e. a 6mm bushing can not be used where a 7mm bushing would be used and vice versa).

The only way to increase or decrease the bearing allowance on a gear box is to purchase a new gearbox shell which allows the diameter wanted.

Further elaboration about bushing diameter will be discussed later on in conjunction with gearbox shells. At this time the only relevant information is to understand the after mentioned differences which delegate basic usage in a gearbox.

Bearing Manufacturers

Area 1000
Systema
Prometheus

[tZ]

Spring

Spring: Allows for the horizontal compression of the piston determining the potential velocity of an automatic electric gun.

Upgrading the spring in an Automatic Electric Gun is one of most common/popular AEG enhancements.

The advantages of a spring upgrade are the ability of being able to control velocity and range. (i.e. increase or decrease velocity/range over the stock manufactures velocity for the desired weaponry).

Velocity Measurement

There are two ways to measure the potential velocity of a spring in comparison to a standard stock spring.

Percentage System
Meter Per Second System

• Most after market percentage system spring manufactures base the percentage measurement from the standard Tokyo Marui AEG muzzle velocity with a 0.20 gram bb (90 m/s or 100%).

• The meter system is a more accurate measurement in terms consistency between gun manufactures (i.e. Classic Army guns typical muzzle velocity exceed 90 m/s. There for, the percentage system does not stand consistent with all stock guns). However, the meter system stands consistent with all springs and is not based off of any stock manufactured spring. It is a system based on meters per second not calculated from a pre derived measurement and based of it like the percentage system.

• Clearing up a common misinterpretation a spring rated 120 % is not read as 120 m/s. It is read as 120 % which calculates to be around 100 m/s.

• However, feet per second (fps) are the common relative measurements used when acquiring spring velocities. the Foot is used in place of the meter to give one a smaller measurement they can relate to (i.e. light years just stands alone as light years. However, to actually understand how far that is a mile measurement can be derived). It’s basically a smaller way of expressing a large number to better understand how large, fast, etc. something is.

• A spring rated 100% does not mean 100 fps and spring rated 120 m/s does not mean 120 fps. The percentage, meter and feet system are all relative measurements that stand alone. However, each can be derived from one another with the proper mathematical calculation in order to due so. (i.e. 2 inches does not mean 2 feet. 2 feet is 24 inches and 2 inches is 1/6 of a foot).

• Theoretical and actual velocity readings will vary. However, the theoretical reading is the best way to acquire a relative idea of potential velocity.

Manufacturers

There are a number of manufactures to choose from when deciding upon a new spring.

Manufactures (corresponding measurement system)

Prometheus (m/s)
Guarder (m/s)
Systema (m/s)
PDI (percentage)
Hurricane (m/s)
Deep Fire (m/s)
21 CA (fps)

• The brand is dependent on desired velocity alone. No pre-determined manufacture produces a best suited/higher quality spring over another on a theoretical or material basis. Higher quality springs only exist via better experience with one brand over another, word of mouth and ultimately opinion. Choose the brand and spring that best suite your automatic electric gun(s) needs.

• Generally uniformity between parts is the best suited way to approach upgrades (i.e. To the best of your ability keep all the parts of the same manufacture).

Precaution

For the most part, the spring velocity will determine further part upgrades needed for best reliability, durability, performance and lifespan of an AEG in conjunction to the spring in use. Generally speaking an AEG with a higher velocity will need increased upgrades over a lower velocity AEG in order to run smoothly.

• Above all else, the bushings must be metal before proceeding to upgrade ANYTHING (i.e. the velocity – spring, gears, etc).

[tZ]

Piston

Piston: Part inside an automatic electric gun gearbox which allows for the horizontal movement of the piston head.

Plastic

Most stock automatic electric guns are manufactured with a standard plastic piston (i.e. Tokyo Marui, ICS, etc). A plastic piston will suffice for a long period of time in a stock automatic electric gun. However, it is suggested the piston be upgraded once a velocity of near four hundred feet per second is established.


• A piston upgrade is NOT a parallel amount of importance unless establishing after mentioned velocity limits or using a tighter diameter barrel


• A piston upgrade is needed once reaching the after mentioned velocity limits because, the added stress of the spring increases stress on the gearbox. A plastic piston lacks the loss of weight many aftermarket pistons have in order to counteract this stress gain for an efficient running replica.


• Also, after market pistons provide the durability needed in conjunction with high velocities. Plastic does not have this durability and is increasingly susceptible to breakage when running higher velocities.


Types

Regardless of material the first issue of concern is the type of piston needed in conjunction with an automatic electric gun.

There are only two types of automatic electric gun pistons.

Standard
Helical (half toothed)

• Most manufactures gearboxes are designed to run with a standard piston (i.e. Tokyo Marui, Class Army, ICS, Airsoft Elite, etc).
• All standard pistons are made to be interchangeable with one another except helical pistons.

Further Elaboration of helical piston use over standard will be discussed more in-depth in the gear section. The only relevant information concerning the two at this time is the need in understanding a helical piston is different then a standard piston and each can NOT be used in conjunction with one another (i.e. a standard piston can not be used as a helical and vice versa).

Material

The piston will be subdued to increased stress dependent on the velocity of a spring and tightness of a barrel. There for, to counter act the added stress on the piston a number of piston upgrades are available.

A piston upgrade is a piston which exhibits a durability gain and weight loss over the plastic piston found in many stock automatic electric guns.


Polycarbonate

Manufactures (polycarbonate)

Area 1000
Classic Army
Guarder
Prometheus
Systema

Polycarbonate pistons are said to exhibit three times the strength over a plastic counter part. In addition they are approximately fifty percent lighter then a plastic piston. The decreased weight of the piston allows for the most efficient rate of fire to be established. Also there will be less stress on the cylinder head and gearbox shell decreasing chances of mechanical failure over a heavier piston such as; plastic or Aluminum. In the end, a polycarbonate piston increases durability, performance and lifespan of an AEG over a plastic piston.


• Some manufactures produce automatic electric guns that come standard with polycarbonate pistons (i.e. Classic Army, etc).
•

Aluminum

After Market Manufactures (Aluminum)

Hurricane
Systema

Aluminum Pistons are heavier then polycarbonate pistons, but the teeth and over all durability is increased in comparison to both plastic and polycarbonate.

• The increased weight of an Aluminum piston will increase the impact on the cylinder head and ultimately the gearbox shell. Caution should be taken when installing an Aluminum piston over a polycarbonate.


• An Aluminum piston tends to increase the stress on the shell of a gearbox making it more susceptible to mechanical failure over that of a polycarbonate.


• Some manufactures such as hurricane have counteracted the added weight gain of Aluminum. This has been done via cutting vents into the side of their aluminum piston to reduce the weight.


• An Aluminum piston with vents cut into it sustains the durability of any standard aluminum piston, but decreases the weight of it.


• Polycarbonate pistons still remain lighter then that of any Aluminum piston with vents cut into it.

Titanium

Manufacturer

Deep Fire

A relatively new innovation to the aftermarket piston market is polycarbonate pistons with full titanium coated teeth. Most polycarbonate pistons offer the first few teeth as a titanium insert but, the fully titanium toothed piston offers all the teeth as titanium. In the end, these pistons offer the same advantages of all polycarbonate pistons but, have the increased durability of the teeth in comparison to regular polycarbonate, aluminum and plastic.

Special Case

As mentioned above most pistons are interchangeable, except for helical. However, pistons exist in the rare that are made specifically for one weapon, gearbox version, brand and/or other special circumstance. One should make them self aware of these occurrences when considering the purchase of a new piston (i.e. Tokyo Marui PSG-1 piston, etc).

High speed

Manufacture

Angel

A high speed piston lacks a few back teeth in order to cycle the spring quicker then that of a standard piston. These pistons are rare, hard to come by and should only be used in conjunction with lower spring velocities (i.e. 250 fps – 350 fps).

[tZ]

Piston Head

Piston head: allows for the outward transition of air from the cylinder to air nozzle.


General

The stock piston head should be upgraded around the same time as the piston.


• However, most Tokyo Marui AEGs require a new piston be bought when upgrading the spring. The spring on Tokyo Marui replicas have an elongated front which helps to better hold the spring to the piston. The stock piston head screws into an elongated part which only works in conjunction with this stock Tokyo Marui spring. There for, once you upgrade the spring you must purchase a new piston on these replicas.


• The piston head can be upgraded with out the need to upgrade the piston.


The special case concerning Tokyo Marui listed above may apply to other manufactures as well (i.e. Classic Army, ICS, etc). One should research the coherence of their stock piston with that of a new spring before purchase.

Materials

Polycarbonate (POM)
Aluminum
Plastic

• Most manufacturer stock automatic electric guns come standard with a plastic or nylon piston head. However, some manufacturers supply a polycarbonate piston head on their stock AEG.


• All piston heads are interchangeable


• Upgraded piston heads come in either polycarbonate or aluminum form. The aluminum versions are heavier. More force on the gearbox shell is created increasing the potential of possible cracking of the gearbox near the nozzle in contrast to polycarbonate pistons. However, polycarbonate pistons are known on occasion to shatter and Aluminum pistons are not known to shatter (break).


Silent piston head

Manufacture

Systema

This piston features a plastic head with a rubber bumper on it to cushion the impact on the cylinder head. This serves to quiet the AEG slightly. These pistons are susceptible to same disadvantages as polycarbonate heads; possibility of shattering with the added advantage of silencing the AEG slightly over Polycarbonate or Aluminum.

Upgrade

Upgraded piston heads aside from material contain holes cut into the front face of the head. The advantages of this modification to the piston head are listed below.


• When the piston is traveling forward the air goes through these holes and forces the o-ring on the piston head outwards to create a more successful seal in the cylinder. Decreasing chances of air leakage in the cylinder.


• When the piston is being retracted for the next shot the, the o-ring collapses down into the channel it resides more compact and quickly because of the vacuum created via the holes.


• The spring cycles with decreased friction allowing for smoother movement of the piston head, piston and spring.



Bearings

Another option to consider is a piston head with bearing(s). Most stock pistons do not come with bearings. However, many upgraded piston heads are supplied with these. The bearing(s) helps in allowing the spring to spin freely when compressing, thereby removing a bit of extraneous force from the system.

[tZ]

Spring Guide

Spring Guide: The part of an AEG gearbox that holds the spring in place.

An upgraded spring guide is one of the first upgrades to consider after the purchase of metal bushings/bearings and a spring.

Types

The type of spring guide which is appropriate in conjunction with any AEG is determined via the gearbox version. Spring guides are not interchangeable between different version gearboxes (i.e. purchase the version spring guide that corresponds to the gearbox version it will be used in).

Material

Brass
ABS plastic
Polycarbonate

Most stock spring guides are made from a cheap plastic material. Once velocities above 350 fps are reached the stock spring guide should be replaced immediately. Depending on your pocket book all after market spring guide materials generally perform the same task well. However, some spring guides are in theory more durable then others (i.e. polycarbonate over brass, etc) there for, one should choose a new spring guide based on their gearbox version, pocket book and estimated appropriate durability per circumstance.

For the most part all after market spring guides share the same durability and strength with some exception as mentioned above.

Bearings

Similarly to piston heads spring guides can be purchased with included bearings. Bearing(s) allow the spring to spin freely when compressing, thus removing unnecessary stress within the system. In addition, the bearing serves to slightly compress the spring a bit more allowing for an approximate (5-10 fps) muzzle velocity gain.

[tZ]

Cylinder

Cylinder: part of the AEG gearbox that holds the air used to propel the ammunition.

General Types

NB (non bore up)
BU (bore-up)

Non bore up cylinders in terms of inner volume are the same as most stock cylinders. The inner diameter stays consistent.

Bore-up cylinders have slightly larger inner volumes then non bore up cylinders. The diameter of these cylinders do not stay consistent from one end to the other. One ends diameter is slightly larger/smaller then the other.



• Bore up cylinders should only be used with very long inner barrels (m16 +)


• In addition, they shouldn’t be used in conjunction with any spring rated below 140 m/s.



Material

Nickel plated
Teflon coated

Most stock cylinders are nickel plated opposed to Teflon coated. It is suggested that all Teflon coated cylinders be used in conjunction with a high speed set up. However, both materials can be used safely in non high speed set ups.

Further elaboration on high speed set ups will be addressed in the gear section.

The major advantage of Teflon over nickel is it is smoother and decreases friction between the piston head rubber and the wall of the cylinder. This allows for the smoother cycle of the gearbox internals to be established.

The cylinder is not of any absolute amount of importance to upgrade. For the most part a cylinder upgrade is left to the discursion of the replica owner; taking into account the exceptions listed below.


Exceptions (as mentioned above)


High speed gear set up

Spring velocity of 140 m/s or above

Very long inner barrel

If one finds the need to upgrade their stock cylinder then the after mentioned data should be taken into account when purchasing and the information below should be reviewed. The information listed below is not mutually exclusive with the information listed above.



Hole Location vs. Barrel Length



Unlike other parts in the gearbox the cylinder is not necessarily interchangeable amongst all automatic electric guns. The type of cylinder needed per circumstance can be determined via relationship of hole location and the length of the barrel which the cylinder will reside.



No Hole: 450-580 mm barrel length


4/5 Hole: 364-460 mm barrel length


¾ Hole: 227-430 mm barrel length


½ Hole: 110-170 mm barrel length



The percentage is not the diameter of the cylinder itself. The percentage is the location of the holes in the cylinder in correspondence to barrel length (i.e. no home means no hole on cylinder, ½ hole means the holes are located halfway between end, ¾ means the holes are located in between the half way and an end and 4/5 means the holes are located near one end).


A better understanding of hole location will be gained once one views upgrade choices for their replica.


All cylinders are interchangeable between gearboxes but, for best performance they must be purchased in relationship to the barrel length of the gun mentioned above NOT the gearbox type


Example: the no hole cylinder can be used in a gun with a v2 gearbox and any other cylinder can be used in the same version gearbox. However, if the barrel lacks the appropriate relationship to the cylinder hole location then the performance and velocity may decrease depending upon circumstance.

If the cylinder hole location is drastically incorrect (i.e. using a ½ hole where a no hole is appropriate) then the ammunition being fired may not be sucked back instead of pushed forward. Thus causing a great deal of agony and mechanical failure which could of easily been avoided.

Precaution

As mentioned above hole and barrel relationship, material and general type stand as separate issues concerning cylinders.

Steps listed in order when purchasing new cylinder

First determine the hole location needed as appropriate per rifle.
Delegate between a NB or BU cylinder type
Choose the material as appropriate

[tZ]

Gears

Gears: The parts(3) that allow for the initial movement of the piston.

General

Automatic Electric gun gearboxes contain three gears.

1.) sector (top)
2.) spur (middle)
3.) bevel (bottom)

All manufacture gear sets contain all three unless stated otherwise.

Types:

Flat(standard)
Helical

Flat gears have teeth with ridges that run perpendicular (90 degrees) to the edge of the gear face. Helical gears have teeth with ridges that run slanted (45 degrees) relative to the gear face.


Example:

(Viewing gears from the side: teeth orientation)


Flat: | | |

Helical: / / /

The difference between them is that for a helical gear more than two teeth mesh (at least partially). More teeth come into contact with the piston during any one given movement reducing the stress of any given tooth of the gear in comparison to a flat gears weight load.. This is due to the fact that the helical cut allows for a more balanced weight distribution over a flat gear cut. In a flat gear cut fewer teeth per movement come into contact with the piston.

Ex. if an item needed to be lifted would this be better done via one person or a great many (just taking into account mass)? Obviously the more people you have the less weight one individual would need to carry.


Item = 500 pounds


Two people carrying it would need to distribute the weight 50/50 or 250 pounds per each. However, if you had five people each would need to carry only 100 pounds. There is going to be a lot less stress on the individuals carrying the item with more people because the large mass is more evenly distributed into manageable amounts.

This concept is in direct relationship to gear teeth. However, the piston is the load and the gear teeth are the individuals. The more teeth interacting with the load the less each tooth needs to carry to hold it up effectively.


Advantages and Disadvantages (flat vs. helical)


The above concept ultimately decreased the chance of stripping and loosing teeth because each individual tooth has less stress on it vs. flat (i.e. is it easier to carry 20 pounds (helical) or 100 pounds (flat)? Carrying 100 pounds would increase the chance of injury vs. carrying 20 pound).

However, helical gears tend to require a much more demanding set up and have less room for intolerances in the system. Generally, helical set ups have an increased probability of mechanical failure over flat gears. Since, flat gears bit on a flat plan they transfer power on a plan in direct relationship to the motion of the piston. However, the curve of helical gear teeth allows for a more sturdy interaction with the piston requiring increasingly close tolerances over flat cuts. Hence, helical gears do not allow as much room for error within the system as flat gears do before a malfunction occurs.

For springs 130 m/s and below a flat gear set up is recommended. A helical set up is advised in conjunction with a spring above 130 m/s.


Pistons relationship to gear type


It is of the up most importance you follow the below guidelines when deciding upon the proper piston to use in conjunction with any given gear set up.


• Flat gears can only be used in conjunction with a standard piston.

• On the other hand, helical gears can only be used in conjunction with a helical piston.

• There is a third type of gear but, it was left out of the above for less confusion. The third gear type is called all-helical. This type of gear set retains the attributes of a helical gear set but, can only be used in conjunction with a standard piston. Since, the teeth which come into contact with the piston are left 90 degrees while the rest retain a 45 degree slant.

Helical pistons have teeth half the length of standard piston teeth.

[tZ]

Motor Gear Relationship

Torque is the relative amount of motor revolutions it takes to complete any desired mechanical cycle.

All automatic electric guns contain motors to drive the force. The motor contains a shaft with a small sector gear attached to it contacting the bevel gear (bottom gear in an AEG gearbox). The bevel gear turns the rest of the gears in relationship. As the gears turn the top gear(sector) has teeth on it that mesh with the piston. Thus the piston pulls back as the sector gear rotates allowing for the completion of a cycle. Each time a new bb is the fired the cycle is repeated. This whole process sums up the basic mechanical workings of an AEG

(The rotation of the gears and motor shaft to complete a cycle is the only relevant information art this time.)

The amount of times the motor shaft must rotate to cycle the piston varies between gun type and manufacture. The motor rotation is not based on a pre established standard. Some guns may only need the motor shaft to rotate 5 times in order to cycle the piston while other, may need the motor shaft to rotate 10 or 20 times.

( I am not certain on any exact number of gearing cycles in correlation to gun. I am just using the above numbers as an example that all guns have different ratios.)


Types of Gears (pt2 - torque)


The torque ratio is dependent on the extent of stress an AEG is subdued to.


• As spring tension/velocity increases the amount of stress on the system increases as well.



• Standard AEG motors are not meant to handle a large increase in load without mechanical failure (overheating, etc).



In order to counteract an increased load torque up gears were born. Torques up gears allow the motor to adjust the number of shaft rotations per cycle to run efficiently in coherence with an increased load (velocity increase/tension of spring).



Concept explained through example


For example purposes lets say stock guns take around 6 motor rotations to cycle a spring (one shot). So the ratio is 6:1. Stock guns are manufactured to run efficiently so we are going to set 6/1 as our (x) variable. Now let’s say in that same gun we decide to upgrade the spring to something like 400 fps. We just replace the spring and bushings.

Now the gun is still going to run near 6 motor shaft rotations per cycle. However, the new spring tension is increasing the tension and stress on the gear box as a whole (making it increasingly subtle to breakage, since AEG gearboxes are only meant to have so much stress on them).

Math


(numbers for example purposes only)


Stock fps: 200 fps
Upgrade: 400 fps


Regardless of the spring the gun is cycling at around one shot per very 6 rotations of the motor shaft. So by deriving the manufacture ratio (what the motor rev/velocity ratio is meant to be) we can determine the desirable ratio which entails the least amount of force on the gun.

6 / 200 = 1 / 33.3 so about (1 / 33) – desirable ratio for best function

Now we calculate the current 400 fps ratio.


6 / 400 = 1 / 66.6 so about ( 1 / 66 ) – current ratio


Compare the two


1 / 66 is about 2 times the suggested ratio.



Thus the added stress is distributed throughout the gearbox and increases the chance of something breaking.

When you add stress to any object you increase the chance of it breaking or malfunctioning.

So now we add some torque up gears to our AEG.

The torque up gears are going to adjust number of rotations of the motor shaft with correlation to torque up ratio. Let’s pretend the torque gears we are installing adjust the motor to 12 motor shaft rotations per piston cycle.



12 / 400 = 1 / 33.3 so about ( 1/ 33)


compare to the original stock gun


1/ 33 = 1 / 33



Thus the establishment of the same ratio has been accomplished and there will be a very minimal gain on stress of the system as a whole. Since, the now the ratio is the same as the original gun. Even though it contains a much high velocity spring.

Furthermore, torque up gears lesson the load and stress but, in turn decrease the fire rate.

( the numbers and ratios used in the above section are for example purposes only. They are not meant to reflect any real life ratios of an AEG. They are just used in place of variables so the basic concept can better be understood.)

Torques gear set purchasing


Torque gears come in a vast amount of ratio.

Manufacture
Systema
Prometheus
Hurricane

• Most manufactures include the velocity range which is appropriate with any given set on the box. Internet retailers will usually include it in the product description.



• Always make certain the ratio is appropriate to run in correlation with your spring/fps before buying.

General ratios

(Standard spring – 120 m/s) - standard torque
(130 m/s +) – high torque

Most manufactures and retailers website include the ratio to spring/ fps state the allowances in form of a chart or description.

High Speed gears

These gears decrease the number the shaft rotations per cycle. In contrast to torque gears these gears will increase the fire rate of an AEG and increase the stress on the gearbox as well. There for, these gears should only be used in conjunction with velocities 100 m/s or below.


• Failure to follow this guideline will end in AEG catastrophic failure. While safe to use in conjunction with lower velocities “deadly” to use with ones higher then recommended.



• User discretion is advised.



Durability


All gears are made from some type of metal.



• To clear up a misconception there exist no plastic gears. All AEG manufactures supply metal gears in their guns (Tokyo Marui, Classic Army, ICS, etc), but the quality between metals differ. Stock gears generally have less strength then after market upgrade gear sets (i.e. torques, high speed, etc).



Upgrades



• However, stock guns can run efficiently and effectively on the stock gears for many rounds. The Replacement of stock gears with aftermarket ones right off is not necessary practice in most circumstances.



• Stock guns will run fine until velocities upward 400 are reached. Once in the range of 400 fps + it is suggested the gears be upgraded right off hand. However, for velocities lower it fine to leave the stock gears until they break.



Breakdown


Gear consideration when purchasing

1.) Helical vs. Flat
2.) Torque vs. High Speed
3.) Ratio coherence to desired velocity

Sources

www.airsoftplayers.com
www.lonestarairsoft.com
www.airsoftgear.com
21stcenturyairsoft.com
mia airsoft posts

[Knief]

This Page was taken from a post of Skipperooo in FAS Tech Forum.
Welcome to FAS [Tech n' Maint Forum] Posted here are collection of technical information from previous forum threads (FAS/AGL) and general facts from experienced veteran gunsmiths and players: Thank you!

DISASSEMBLY: Step by step guide on disassembling TM Gearboxes at airsoftguns.com
Click Here for TM Version 2 Gearbox Disassembly Guide
Click Here for TM Version 3 Gearbox Disassembly Guide

Click Here for TM M16 Series Gun Disassembly Pic Guide

**parts graphic reference at filairsoft.com/airsoft106.htm

SPRINGS: (Approx. Settled Spring FPS on .20gBB)
Stock Gun (brand new gun) = 270-290 FPS
CQB Gun: M100 / SP100 / PDI120% = 330-350 FPS << FAP CQB Standard
Standard Field Gun: M120 / SP120 / PDI170% = 390-410 FPS [.20gBB stable] << COMMON UPGRADE
Std High Field Gun 1: M130 / SP130 / PDI190% / PDI210% = 440-460 FPS [.20gBBmin .23gBB stable]
Std High Field Gun 2: M140 / SP140 / PDI240% = 470-490 FPS [.23gBBmin .25gBB stable]
Sniper Field Gun 1: M150 / SP150 / PDI270% = 510-530FPS [.28gBB stable] << FAP Sniper Standard
Sniper Field Gun 2: M160 / SP160 = 550-580FPS [.30g/.36gBB sweet-stable] << rat buster
Sniper Field Gun 3: M170 / SP170 = 580-600+ FPS [.36g/.43gBB sweet-stable] << cat buster
Spring Power Chart filairsoft.com/airsoft103.htm
BB goes wild = BB too light -- BB range seems near = BB too heavy

GEARS: (Does NOT affect Gun FPS, only ROF)
Infinite=(1) Ultra=(2) SuperTorqueUp=(3) TorqueUp=(4) StockRatio=(5) FastGear=(6)
>> Numbers indicate "car-gear-shift". *Small batts (non Sub-C) DOWNSHIFT to next LOWER gear. <<
Common Gear-to-Spring Setup for Big Batt (engine) (Sub-C):
Fast Gears (6) - UP TO M100 / SP100 / PDI120%
Stock Gears (5) can 'safely' handle up to M130, SP130, PDI190% <<<< on 9.6v 1700mAh(min)
Torque Up Gears (4) - M130 / SP130 / PDI190%-210% or LOWER
Torque Up Gears OR Super Torque Up (4/3) - M140 / SP140 / PDI240%
Ultra Torque Up Gears (2) - M150 / SP150 / PDI270%
Ultra or Infinite Gears (2/1) - M160 / SP160 << Needs minor machining to fit on Ver.2 GearBox
Infinite Torque Up Gears (1) - M170 / SP170 << Needs minor machining to fit on Ver.2 GearBox
*Some Gear set won't fit on some reinforced Gearbox-CHECK first before you get one.
*No known machining on stock ver.3 GearBox to fit any gear set.
*AVOID using Bearing Bushings on M120 above. only for soft springs

M130 / SP130 / PDI190%-PDI210% on STOCK Gears will last Approx. 5-10 months (depends on use)
Stock Gears - Low Cost, nice ROF. will not last long. (cast alloy)
Flat Gears - Noisier, Cheaper. More durable (steel)
Helical Gears - Silent. Expensive. shimming sensitive (steel) <<Avoid pairing w/ Bearing Bushings

BATTERY: (Does NOT affect Gun FPS, only ROF and Rounds of fire)
Voltage = Rate of Fire (ROF) mAh = BB-Rounds (Power/Stamina)
BIG INTERNAL Standard Battery Size [Ni-CAD]:
M4A1 - 9.6v 1700mAh (Fat-long AA) V-Type 12v 1700mAh(max)
M4A1 Patriot - 12v 1700mah (Fat-long AA) Circular config
G36C - 9.6v 1500mAh (Fat AA)
M733 - 9.6v 1500mAh (Fat AA) Chako-Type 12v 1700mAh(max)
AK 47/Spetz - 10.4 2400mAh (Sub-C) 12v(max)
M16A1/A2/VN/SR16 - 9.6v 2400mAh (Sub-C) 13.2v(max)
CAR15 - 8.4v 600mAh (Small) 1500mAh (max) (Fat AA) 2-separates
P90 - 9.6v 1700mAh (Fat-long AA) J-Type
G3A3,G3SG1,MP5A4,MP5SD5 - 9.6v 2400mAh (Sub-C) Straight
MP5SD6 - 9.6v 1500mAh (Fat AA) V-type
MP5A5 - 9.6v 1100mAh (Slim) Chako-Type << (?)
Steyr AUG - 9.6v 1700mAh (Fat-long AA) Box-Type
PSG-1 10.8v 1500mAh (Fat AA) 13.2v(max)
M16 Dummy/Ready MAG - 9pcs 10.8v 1700mAh (Fat-long AA)
AN/PEQ 2 Dummy Laser Box - 9.6v 1700mAh (w/laser) 12v 1700mAh(max)

Approx. Battery-to-Rounds Capacity: [NiCd] (on M120 Stock Gears, EG1000)
9.6v 600mAh = <500 rounds (Small) Sanyo KR600AE 9.5mOhm Internal Resistance
9.6v 1100mAh = 1,000 rounds (Slim) Sanyo KR1100AAU 19mOhm Internal Resistance
9.6v 1500mAh = 1,400 rounds (Fat AA) Sanyo KR1500AUL 16mOhm Internal Resistance
9.6v 1700mAh = 1,800 rounds (Fat-long AA) Sanyo KR1700AU 17mOhm Int. Resistance
9.6v 1900mAh = 2,400 rounds (Sub-C) Sanyo N-1900SCR 4mOhm Internal Resistance
9.6v 2000mAh = 2,600 rounds (Sub-C) Sanyo KR-CH 6.5mOhm Internal Resistance
9.6v 2400mAh = 3,100 rounds (Sub-C) Sanyo CP-2400SCR 4.5mOhm Internal Resistance
9.6v 3000mAh = 3,800 rounds (Sub-C) Sanyo HR-SCU [Ni-MH] 5.3mOhm Internal Resistance
*can someone confirm this rounds guesstimation--
BEST BUY: 9.6v 1700mAh(small-type) 9.6v 2400mAh(large-type)

Approx. CHARGING Time on 1000mAh Output Charger:
600mAh = 36mins(min) 42mins(std) 48mins(max)
1100mAh = 1hr 6mins(min) 1hr 19mins(std) 1hr 30mins(max)
1500mAh = 1hr 20mins(min) 1hr 48mins(std) 2hrs 7mins(max)
1700mAh = 1hr 42mins(min) 2hrs(standard) 2hrs 24mins(max)
1900mAh = 1hr 53mins(min) 2hrs 18mins(std) 2hrs 43mins(max)
2000mAh = 2hours(minimum) 2hrs 24mins(std) 2hrs 48mins(max)
2400mAh = 2hrs 23mins(min) 2hrs 54mins(std) 3hrs24mins(max)
3000mAh = 3hours(min) 3hrs 37mins(std) 4hrs 13mins(max)
*Charger should be 1 to 3 volts higher voltage than total battery voltage
Go over to digibattery.com for more battery-charging-time calculations
DISCHARGING: Number of batteries in a Pack = Max discharge volts.
(ex. 9.6v = 8cells in a pack = 8.0v is the maximum discharged voltage)

PISTON: Depends on your spring and trigger abuse.
M140 Above = Aluminum Piston (for ratatat players)
. Choice1: ICS Aluminum Piston
. Choice2: Systema Aluminum Piston
*if compatible, get the half-tooth to lessen the weight
M140 Below = Polycarbonate Piston
. Choice1: Guarder Polycarb Piston (blue)
. Choice2: Tokyo Marui Stock Piston (white) <-- polycarbonate too
. Choice3: Systema Polycarb Piston (black) << brittle bad choice
AVOID the RED PISTON-Systema Polycarb (defective) there's a newer version
*have'nt tried the TGS(blue) nor the TOP yet, but it looks promising <-- pls review
*some use polycarbs on m140 above but with trigger care

CYLINDER: (cylinderVolume-to-barrel-ratio) 2 is to 1 (standard)
Marui Stock Cylinders:
1. Closed Cylinder = 27.1cc 450mm(min) 580mm(max) barrel length
2. XM Cylinder = "4/5 hole" = 364mm(min) 460mm(max) barrel length
3. M4 Cylinder = "3/4 hole" aka Type-2 17cc - 229mm(min) 430mm(max) barrel length
4. MP5K Cylinder = "mid hole" 9cc 110mm(min) 170mm(max) barrel length




Systema NB Standard and BoreUp Parts:
1. Type-0 Cylinder (closed) fits M16-A1,VN,A2,G3-A4,SG1,SIG550,AUG
2. Type-1 Cylinder (tip hole) for XM177, M4, AK47, AK47S, SIG551
3. Type-2 Cylinder (XM hole) for MP5-A4,A5,SD5,SD6, MC51,SIG552
4. Type-3 Cylinder (M4 "3/4" hole) for MP5 PDW
5. Type-4 Cylinder (MP5K mid hole) for MP5K
*BoreUp Closed 29.4cc = 500mm(min) 600mm(max) barrel length


KM Cylinder Parts:
*Intercept Cylinder 59 barrel length from 450mm to 590mm (Type 0)
*Intercept Cylinder 45 barrel length from 250mm to 450mm (Type 2)
*Intercept Cylinder 25 barrel length from 100mm to 250mm (Mid-hole)

*To avoid confusion, don't mix brand model names, just model equivalence
*TM M733 by stock is closed cylinder (Type 0) -over ratio

RATIO Guide: Standard-Efficient Ratio is 1.5 is to 1
2-2.5 : 1 for springs up to M130 --- 2.5-3.0 : 1 for strong springs M140 -> UP
<needs further research>

BARREL: (inner barrel length)
650mm/25.59in PSG-1 (extended)
595mm/23.42in APS2 OR
589mm/23.18in PSG-1
550mm/21.65in M16A1/VN/A2,AUG (extended)
534mm/21.02in Sig550
509mm/20.03in M16A1/VN/A2,AUG
472mm/18.58in Famas SV/F1
469mm/18.46in G3-A3/A4,SG1
455mm/17.91in AK47,AK47s
444mm/17.48in M60
407mm/16.02in M4A1 M653E2 (extended)
395mm/15.55in APS2 SV
369mm/14.52in HK51
363mm/14.29in M4A1,RIS,SR-16,XM177ED,Sig551
300mm/11.81in M1A1,AKBetaSpetz, M733
285mm/11.22in MC51
247mm/9.72in Car15,P90,G36C, SIG552
245mm/9.64in UZI - 400mm/15.74in (extended)
229mm/9.01in MP5A5/A4/SD5/SD6
170mm/6.69in MP5K-PDW (extended)
141mm/5.55in MP5K-PDW
110mm/4.33in MP5K

MOTORS:
TM EG560 (famas)
TM EG700 (need more spec info)
TM EG1000 27,552rpm 1,407.00G.cm Torque
Systema "Genuine" 29,825rpm 1,6999.83G.cm Torque
Systema "Hi-Speed" 37,400rpm 1,915.99G.cm Torque
Systema "Hi-Torque" 32,302rpm 1,932.49G.cm Torque
Systema "Super Hi-Torque" 34,787rpm 1,998.47G.cm Torque
Eagle Force Hummer 1100 (high-speed)
Eagle Force Hummer 1300 (super-high-speed)

GAS: (for gas guns/pistols)
Freon12/Flon12 (94psi) = HFC134a (97psi) a.k.a. Green Gas
Freon22/Flon22 (140psi) a.k.a. TOP Gas, Taiwanese Green Gas,Omega Gas,ToyJack Gas
RED Gas = a bit higher pressure (?) than TOP Gas
BLACK Gas = highest pressure for airsoft <carbon<myth?
*pressures on 30C / 86F manila temp. / gas expansion speed differs from each type of gas

~Ace

[Knief]

Something for everybody to remember for these guides is that a lot of these numbers are approximations, and may not give you similar results. What velocity a spring puts out depends in 10 other factors in the gearbox and the rest of the gun as well as in the production variances in the spring. A battery that isn't fully drained will charge in less time. The number of rounds each battery can fire before dying is completely variable depending on things like temperature, spring stiffness, how efficiently your gearbox runs, how effeciently your wiring delivers current, and many more factors. Don't take any of this information as gospel, but rather, use it for what it is, a guide to get you closer to what you want out of your gun.

[Knief]

Updated Barrel length list:

Source:
www.atfreeforum.com/phpbb/viewtopic.php?mforum=asboard&p=1394

110mm - MP5K
141mm - MP5-PDW
182mm - MP7A1
195mm - UMP/UMG
208mm - G3 SAS
229mm - MP5A4, MP5A5, MP5SD5, MP5SD6, AK-47 Beta Spetsnaz
247mm - G36C, P90, CAR-15, SIG 552
280mm - CA SAR M41 FS Offizier, CA M15A4 CQB
285mm - MC-51
300mm - M1A1 Thompson, TM M733, G&P M4A1 Commando
304mm - G&G FS51 Fixed Stock
355mm - G36K
363mm - M4A1 (CA M15A4 Carbines), SR-16, S-System, TM XM177-E2, SCAR, G36K, M249 Para
420mm - SOC-16, CA M14 Scout
422mm - M249 (non-para)
429mm - CA 33E
455mm - AK-47, AK-47S, AK-74M
463mm - SLR-105, RK-103
469mm - G3 SG1, CA SAR Taktik
472mm - FAMAS F1, FAMAS SV
475mm - VFC MK43 Mod 0
495mm - G36E
500mm - M14
509mm - M16A1VN, M16A2, AUG,CA G3
510mm - L85
534mm - SIG 550
550mm - M16A2 (Long), M16VN (Long), AUG (Long), King Arms FN FAL
590mm - TM PSG-1
650mm - TM PSG-1 (Long)