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Purpose

Gate 3 will provide a more detailed analysis of the Tippmann 98 Custom Paintball Marker by examining the product’s components more thoroughly and discussing their significance in relation to the product’s overall function and interaction between other components.

Coordination Review

Cause for Corrective Action

After Gate 2 was completed, Group 28 planned for Gate 3 by planning out what tasks needed to completed with the time that we had. The weeks preceding the deadline for Gate 3 had many time conflicts for group members, due to exams and time scheduled for studying. Thus, most of the group members opted to delay progress on Gate 3 material until after they had time to devote to it. The group decided to work on the weekend directly following exams; this decision was followed through with and a great majority of pre-wiki was completed. Though the group decided to allot their time towards studying for exams and such, most of the work for Gate 3 was accomplished for at the rescheduled time. Group 28 still had problems with working on the Gate in an orderly, efficient manner but still managed to devote an equal amount of time later on.
Nearing the deadline of Gate 3, the group has yet to discuss work on Gate 4 which will need to be addressed before the Fall break. If a plan for Gate 4 is not discussed prior to the break, there will only be less than a week to have to work on the Gate.

Product Evaluation

Component Summary

The following is a table with every component of the Tippmann 98 Custom Paintball Marker. The table will provide several different types of information on the components :

Part (Manufacturing) number
Component name
Material composition of the component
Manufacturing process(es) used to construct the component
Component’s function
Picture of the Component

Component Summary Table
Part Number	Part Name	Material Composition	Manufacturing Process	Function	Picture
98-39	Stock Barrel	Aluminum	Turning and Drilling	Channels the paintballs out of the marker chamber
02-17	Front Bolt	Plastic	Injection Molding	Impacts paintball by CO2 purpulsion
98-16	Linkage Arm	Steel	Drawing	Ensures the bolt system moves together, by linking the front and rear bolt together.
98-21NR	Custom Power Tube	Plastic	Injection Molding and Drilling	Encases the Valve, and directs the flow of CO2 gas forward when the marker is being fired.
98-V	Valve Complete	Comprised mostly of Steel and some Plastic parts (Dissection of the Valve would yield more information)	Due to the complexity* of this part, several processes were used for each internal part Investment Casting for the Valve Body, Valve Plunger, and Plug. Injection Molding for O-Rings Extrusion(then shaping) for Valve Spring	Receives and contains the CO2 from the gas line, until the marker is fired; upon the rear bolt striking the valve, CO2 is released through the power tube.
TA05101	Rear Bolt	Steel	Die Casting, then Machine Drilling	Directly strikes the Valve when the marker’s triggered pulled in the “cocked”** position
TA5005	Rear Bolt Plug	Plastic	Injection Molding	Housed within Rear Bolt and guides the Drive Spring, and thusly the Guide Pin
CA-14	Drive Spring	Steel	Extrusion then shaped	Stores potential energy when compressed(“cocked”** position), which transfers to the Rear Bolt if the marker’s trigger is pulled.
CA-15	Guide Pin	Stainless Steel	Drawn then Forging	Prevents the Drive Spring from deforming or being misplaced between the End Cap and Rear Bolt.
98-57	Buffer O-Ring	Rubber	Injection Molding	Absorbs force of Rear Bolt when marker is “cocked”**
98-05	End Cap	Plastic	Injection Molding	Encloses the back of the Marker Chamber, and provides a support for the end the Guide Pin and Drive Spring.
98-13	Bolt Handle	Steel	Turning then Drilling then Grinding for handle portion	Connected to the Rear Bolt(and Plug) and secured by the Drive Spring, allows the user to pull back the Rear Bolt into the “cocked”** position.
98-28P	Rear Sight	Plastic	Injection Molding	Allows the user to have a direct perception of where they might be aiming, also known as a Line of Sight.
TA-05003 & TA-5004	Split Grip(Left & Right)	Plastic	Injection Molding	Surrounds the handle portion of the Marker Casing, which provides a better grip for the user.
98-07L & 98-07R	Front Grip(Left & Right)	Plastic	Injection Molding	Fastened to the front of the Marker Casing by a Long Receiver Bolt, Provides a convenient grip for the front of the gun.
98-36A	Trigger	Plastic	Injection Molding	When the user squeezes the Trigger and the rear bolt is “cocked”**, the sear will be lifted and allow the rear bolt to fire.
02-35	Sear	Steel	Die Casting	If in proper position, the Rear Bolt will be fixed in a single position with only the Sear preventing it from moving forward; this is the “cocked”** position.
98-38	Trigger Guard	Plastic	Injection Molding	Provides a minor barrier to foreign objects hitting the trigger accidently; a cautionary component to prevent misfires.
98-20	Trigger Spring (Yellow)	Steel	Extrusion then shaped	Provides a force to the Trigger which prevents it from interacting with the sear
02-20	Sear Spring (Blue)	Steel	Extrusion then shaped	Provides a restoring forces that cause the Sear to rotate about the Sear Pin (Black); Allows the Rear Bolt to remain “cocked”**.
98-33	Receiver Dowel Pins (4)	Steel	Extrusion	Provides support and pivot points for the Trigger and prevents the Sear from being moved too far upward or downward.
CA-36	Sear Pin (Black)	Steel	Extrusion	Provides support and acts a pivot point for the Sear.
98-37N	Safety	Plastic	Injection Molding	If pushed inward, the Trigger cannot be squeezed, vice versa.
TA05101	Custom Receiver (Left)	Aluminum Alloy	Die Casting	The Left side of the overall casing; most notable feature is the slot opening near the back side for the Bolt Handle to move back and forth.
TA05102	Custom Receiver (Right)	Aluminum Alloy	Die Casting	The Right side of the overall casing; most notable feature is the opening for the Hopper to feed paintballs into and latch for the Feed Elbow to mount on.
98-14	Front Sight	Steel	Die Casting	Helps the user aim the marker; with the Front Sight Spring, this component is able to secure the Feed Elbow and prevent rotation about the latch which it is mounted on.
98-44	Front Sight Spring	Steel	Extrusion and shaped	Forces the Front Sight upward which prevents the Feed Elbow from rotating about off the Marker Casing.
98-15	Front Sight Pin	Aluminum	Extrusion	Acts as a pivot point for the Front Sight.
FA-18	Ball Latch	Rubber/Plastic	Injection Molding	Prevents paintballs from rolling out of the barrel when marker is not firing.
98-09N	Gas Line	Stainless Steel	Drawing (Weaved Steel Cable)/Die Casting (Solid Ends)	Connects the Tank Adapter with the Valve/Power Tube, thus being the primary means of transferring CO2
98-06	Tank Adapter	Plastic	Injection Molding	Regulates the amount of CO2 coming from the affixed CO2 Tank.
98-04	Feed Elbow	Plastic	Injection Molding	elbow joint designed to conform to Custom Receiver (Right) and the bottom opening of the Hopper; allows paintballs to feed from hopper into marker chamber.
Not Available	Hopper (Left & Right)	Plastic	Injection Molding	Identical Halves of shell, which holds approximately 200 paintballs; allows paintballs to feed/fall through Feed Elbow.
Not Available	Hopper Screws (6)	Stainless Steel	Cold Forging	Fastens the two halves of the hopper together.
98-26	Valve Lock Bolt (2)	Stainless Steel	Cold Forging	Secures the Valve/Power Tube from moving inside the marker chamber
98-01A	Receiver Bolt (Short) (5)	Stainless Steel	Cold Forging	Secures the Right and Left sides of the marker casing together.
98-01B	Receiver Bolt (Long) (1)	Stainless Steel	Cold Forging	Secures the Right and Left sides of the marker casing together; also secures the Front Grip(Left & Right) to the marker casing.
CA-02A	Grip Screw (2)	Stainless Steel	Cold Forging	Secures the Split Grip (Left & Right) to the marker casing.
PL-01A	Adapter Bolt (Short)	Stainless Steel	Cold Forging	Secures Tank Adaptor to marker casing.
98-06A	Adapter Bolt (Long)	Stainless Steel	Cold Forging	Secures Tank Adaptor to marker casing.
CA-08B	Adapter Nut (2)	Stainless Steel	Hot Forging	Housed between marker casing and allows the Adapter Bolts(Long & Short) to fasten and secure properly.
98 Custom Parts List * - the disassembly of the Valve is not advised since re-assembling the Valve would be near impossible with special tools. A diagram of the inside was referred to speculate on the manufacturing of the Valve and its inner components. ** - The “cocked” position is when the rear bolt is being held back by the sear and the spring is being compressed. In this state, this system has potential energy which will be released when the trigger is squeezed or the sear is displaced. The following picture is what the marker looks like in the “cocked” position. Internal View of “Cocked” Position

Product Analysis

Measuring Component Complexity

Component complexity is not normal unit that can be measured through normal means, so a scale measuring certain key features of each component will produce values that will provide a sense of the level of complexity.
A 0 – 3 point scale will be used for each feature:

0 – The component has none of this feature
1 – The component has very little of this feature
2 – The component has a moderate amount of this feature
3 – The component has a lot of this feature

And the Key Features being considered are:

Material Composition Diversity: which takes into account how many different distinct materials (metals, polymers, wood, etc.) the component is composed of.
Manufacturing Process: which takes into account how difficult or complex the process to make the component was.
Energy Interaction: which takes notice of how often and to what magnitude the component interacts with forces and transfers of energy (gravity, changes in kinetic, potential, internal energy, non-atmospheric pressures, etc.)
Geometry: which considers how abstract or uncommon the geometry of the component is. An ergonomic viewpoint may be considered, since complexity is related to how well the component geometry might suit the user.
Component Mobility/Movability: which considers if the product moves unnaturally or is prone to being displaced for its normal position. This feature will also consider removability and the ability for the component to freely move on its own or if the user wishes it be moved.
Component Interaction: which considers the interaction between sub-systems and other components. Obviously, the more interactions a component has the more varying factors and function are associated with it.

When all these features have being given a rating from the afore-mentioned scale, a weighted average will be taken to determine how complex the component is. Simply put, a smaller number will have less complexity (simplicity) and a larger number will be more complex (abstract).
The formula is determined by giving key features more contribution towards complexity than others:
Complexity(C) = 0.10(MCD) + 0.10(MP) + 0.25(EI) + 0.20(G) + 0.15(CMM) + 0.20(CI)
Each term is simply written as the first letter of each feature (Manufacturing Process = MP)
The highest obtainable score is 3 (Very Complex) while the lowest is 0 (Very Simple)

Before analyzing all of these component, a general remark about the environment in which they function/ operate will be made: Every component discussed below operates in relatively same environment, which is any climate/weather or terrain a paintball match would be set in: ranging from snowy to dry and hot or rocky to grassy terrain. Even the components which are housed inside the paintball casing are susceptible to these environments, as the casing is not a well-sealed apparatus.

Hopper

Component Function

Outside View of Hopper

Inside View of Hopper

The hopper’s sole purpose is to feed paintballs into the paintball marker. This is achieved with the aid of gravity, which will cause paintballs to go downwards towards an opening at the bottom of the hopper, then through the feed elbow, and finally into the marker chamber. For this hopper in particular, the action of feeding the paintballs is not quite accurate, since gravity does all of the work and the hopper is mainly a containment unit; there are no additional forces which would force the paintballs down more efficiently or more quickly.
In order to fill the hopper with paintballs, the user has to simply pour the paintballs into the opening which is covered by fitted plastic lid that acts about a hinge.

Component Form

The hopper is in the shape of a “bean” and is composed of rigid, black plastic looks with the exception of the clear plastic lid.
Other notable dimensions/properties are:

Symmetrical down its longest side (where it separates into halves)
Two circular openings at the bottom (13/16 inches Diameter) and at the side facing towards the user (2.25 inches Diameter)
Six screw wholes for the relevant screws to fasten the two identical halves together
Average thickness of 3/32 inches
Semi-matt surface finish on the outside and glossy, smooth finish on the inside
Right halve weight – 2.36 oz; Left halve weight – 2.18 oz; Lid weight – 0.46 oz
Average height of 3.5 inches (not including the bottom opening), Length of 8.5 inches, and Width of 3.5 inches
”MADE IN CHINA” mark on the outside in small print, the company logo on both sides, and several drafts on insides of halves
Holds approximately 200 paintballs
The bottom opening diameter is identical to the top opening of the Feed Elbow’s top diameter

From these observations, some information can be inferred about the consideration that went to the design of the hopper. The hopper is in general a lightweight, rigid plastic shell meant to simply hold one object. Also, the aesthetics of the hopper are not particularly amazing or impressive. With this in mind, the designers and engineers at 32 degrees (the manufacturer of this particular hopper) decided to build a universal, economical hopper that can be considered an industry standard for all paintball markers. With a price of approximately 4 US Dollars, the production of this hopper was meant to be simple, basic and straightforward to its purpose (feed paintballs); the unimpressive yet efficient design of this component is a reflection of that.

Manufacturing Methods

In order to produce a basic hopper at a very affordable price, the most economical choice was to create the hopper out of plastic, a very inexpensive material compared to metal or wood. And to form the plastic, the most economical method would be Injection Molding, which is economical for mass production. Also, the overall shape of the hopper is relatively simple, with no abrupt changes in curvature or finely detailed aesthetics, so the initial mold for the hopper would be cheaper to produce than one requiring a costlier mold for complex geometry. With only two halves that are almost identical and a flat and simple lid, the molds needed would not have to be extremely intricate nor require any additional R&D. Thus, the overall the design of this hopper is suited well to economic advantages of Injection Molding and was thusly designed around that concept.

Component Complexity

The component complexity can be considered accordingly :

Material Composition Diversity: A rating of 1, since only a simple plastic of black or clear is used, and simple stainless steel screws are used.
Manufacturing Process: A rating of 1, since Injection Molding of this degree is straightforward and relatively easily
Energy Interaction: A rating of 2, since the component is completely reliant of gravity, as is the nature of a gravity-fed hopper
Geometry: A rating of 2, since the design is simple in terms of production but abnormal compared to simple geometric figures (cylinders, rectangles, circles, etc.)
Component Mobility/Movability: A rating of 2, since the component has a lid which will be repeatedly opened and shut, and the hopper is separate from the main body of the marker (actually a third party product), which actually makes this component completely removable if desired.
Component Interaction: A rating of 1, since the only interaction is the Elbow Feed, which only consists of paintballs being fed through.

Applying the formula: Complexity = 0.10(1) + 0.10(1) + 0.25(2) + 0.20(2) + 0.15(2) + 0.20(1) = 1.6

Feed Elbow

Component Function

Inner-side View of Feed Elbow

Backside View of Feed Elbow

The Feed Elbow’s name is very revealing of its function, as it is an elbow joint which allows the feeding of paintballs. The bottom hopper is affixed to the top of the elbow joint, and the bottom/side is mounted on the side of the Custom Receiver (Right) via an impermanent hinge. The feed elbow is the intermediary step from the hopper to marker chamber, and simply directs the paintballs from the hopper to the chamber. The feed elbow is also restrained to the casing by the front sight which prevents the component from rotating about the hinge and away from the casing.

Component Form

The Elbow Feed is made of black plastic and has a few metal components that serve the only purpose of mounting it to the casing.
Other notable dimensions/properties are:

An average thickness of 1/8 inch
Weight of 1.79 oz
Elbow bend of 40 degress
Top opening diameter of 1 inch (not including thickness)/Side opening diameter of ¾ inch (not including thickness)
Average Width of 1.75 inches, Total Height of 3 inches, and Height from top to bottom of side opening of 2.125 inches
Draft marks and parting lines
Semi-matt surface finish with no aesthetics
Symmetrical down its front face with side opening facing forward
The general geometry changes from an open cylinder at the top opening, into a elbow joint a third of the way down, and then an opening which fits the geometry of the side of the marker casing

From these observations, the Elbow feed is another straightforward component that only has the features necessary to perform its function. The simple, black and semi-matt plastic is a cheap and basic material that is very common, and serves the purpose of being cheap, economical, and consistent with the rest of the outside components of the marker. Though the people who designed this component were not from the same manufacturers as this component, the theme is still the same, simple and economic parts that perform their function without unnecessary actions.

Manufacturing Methods

Very similar to the Hopper, the Elbow Feed has been constructed with Injection Molding in mind, since the specifications needed to conform to the side of the casing and allow the transfer of paintballs does not have to be perfect, there can be some more for error. Injection molding will also have no impact on the performance of marker, but so would any other method of manufacturing, too; thus, there would be no reason to design an Elbow Feed with an intricate design and composed of extremely high quality material which might require a more complex manufacturing process.

Component Complexity

The component complexity can be considered accordingly :

Material Composition Diversity: A rating of 2, since additional metal components are necessary to mount it to the casing. The primarily plastic component is reliant upon these metal fixtures
Manufacturing Process:A rating of 1, since Injection Molding is a relatively simple process, and this mold would consist of only a single part
Energy Interaction: A rating of 1, The component will only experience the weight of the Hopper and the impact of very light paintballs, which will have no effect (deformation or wearing) on the to the plastic its constructed of.
Geometry:A rating of 2, since the geometry changes several times, yet is not too extreme or abstract.
Component Mobility/Movability: A rating or 3, since the component has to rely on a hinge and be secured by the front sight. This component is also completely removable and can be considered optional by the user.
Component Interaction: A rating of 2, since the component must interact directly with the Hopper and the chamber, but only contributes passively by allowing the paintballs to get from point a to b.

Applying the formula: Complexity = 0.10(2) + 0.10(1) + 0.25(1) + 0.20(2) + 0.15(3) + 0.20(2) = 1.8

Marker Casing (Custom Receiver Left & Right)

Component Function

Outside View of Casing

Inside View of Casing

Marker Casing’s primary function is to house the internal components, such as the valve and bolt sub-system, and act a device that can combine with external fixtures, such as the grips, barrel, tank adaptor, hopper, and elbow feed. Along with being the central fixture of the paintball marker, the casing is the primary means which allows the user to properly interact with the marker and the other components; when the other components are properly supported/constrained, the functions of those other components will perform as they should, since they were designed to operate with the casing.

Component Form

The most distinguishing trait about the casing is the similarity to a standard issue handgun. As the handgun is best suited for firing projectiles with just the pull of the trigger, so is the paintball marker casing, which mimics the generic layout of the handgun; a hand-grip-friendly handle, a trigger located near the expected placement of the index(trigger-pulling) finger, and a single barrel that will contain ammunition and propulsion for that ammunition. This generic layout is intuitive to new users and very common to users with prior firearm/water gun experience. However, certain modifications are made to account for the fact that this is a paintball marker and requires different ammunition and sources of propulsion. The most apparent modifications are the diameter of barrel and chamber to accommodate the paintballs, and the method in which the ammunition is contained and fed, the hopper and feed elbow.

Other notable features are:

The casing is composed some type of aluminum alloy
Height of the casing(excluding the front and back handle) – 2 inches/(including the handles) – 5.75 inches
Length(excluding back handle) – 10.75 inches/(including back handle) – 11.25 inches
Total Weight of casing – 23.51 oz / Left – 11.81 oz / Right – 11.70 oz

Notable differences between the right and left sides are:

Custom Receiver Left	Custom Receiver Right
Horizontal Slot for Bolt Handle, to allow cocking. Velocity Adjustment Opening Product name/logo in bold gray letters “Push Safe” text to point out that if the Safety is pushed in on this side, the marker will be toggled in “safe mode” Side which Receiver Bolts are fastened to	Opening and hinge to allow Feed Elbow to attach to “Push Fire” text to point out that if the Safety is pushed in on this side, the marker will be toggled in “fire mode” Side which Valve Lock Bolts are fastened to Engraved Warning label and product patent number

From this information, the two halves of the casing continue this product’s theme of simple and straightforward components. In order to appeal to the masses and gain the reputation of a “standard” paintball gun, the 98 Custom’s main most apparent feature, the casing, mimicked many features of the standard handgun. However, after taking into account the necessity to scale this design to accommodate the function of firing paintball and remain an affordable marker, an aluminum alloy was used to make the casing rather than steel. A casing composed of this material would be cheaper yet still have enough durability and strength to manage the other components; steel could be used but the casing would be too difficult to handle, and if plastic was used it would be cheaper but sacrifice durability over the lifetime of the component. Apart from the physical properties of the casing, the visual aspects, specifically the shape of a firearm, is a constant reminder that the paintball marker can still cause injury and should not be misused; thus, the choosing the shape of a handgun will be a signal to the user and others that this is not a toy.

Manufacturing Methods

With consideration to the apparent theme of simple and straightforward, constructing the casing out of almost identical halves and of a fairly affordable material would not cause any drastic sacrifices to the performance of the marker, and would provide ease of assembly/disassembly for the user. In order to support several components on the inside and outside, as well as to allow openings in various spots, the manufacturing method would need to abide these requirements in order to successfully create the casing. While machining and forging could be used, the much simpler method of die casting was used for each casing side. Die casting could easily and economically accommodate an aluminum alloy casing that would need to be relatively flat, simply curved, and require holes and openings in several spots. This method would produce dimensionally consistent component at an economical cost if they are mass produced.</p>

Component Complexity

The component complexity can be considered accordingly :

Material Composition Diversity: A rating of 0, since the casing halves are composed of a single material, which means there is no composition diversity.
Manufacturing Process: A rating of 2, since the product required two separate molds for each casing halve, and then after the die casting, probably some post-processing to allows screws and bolts to fasten the two sides.
Energy Interaction: At rating of 1, since the component when assembled with all other components, will not withstand any forces that may cause harm to it. When fastened together, the casing can be considered a solid, durable metal housing.
Geometry: A rating of 3, since the profile of the casing halves is very exact and has every component fit within or on the casing. There is no definitive name of the geometric shape might be.
Component Mobility/Movability: a rating of 0, since the component will not move or be displaced when fastened, with exclusion of the user moving the entire product.
Component Interaction: A rating of 3, the component interacts with almost every component in the product, and many of the other products are completely reliant on the casing in order their function to be carried out.

Applying the formula: Complexity = 0.10(0) + 0.10(2) + 0.25(1) + 0.20(3) + 0.15(0) + 0.20(3) = 1.65

Rear Bolt & Rear Bolt Plug

Component Function

Rear Bolt

Rear Bolt Plug

The Rear Bolt and the Rear Bolt Plug coincide and rely on each other to perform their overall function: which is to provide the firing force to actuate the valve and release the pressurized gas. While this is the overall function of both these components combined, the Rear Bolt and Plug have several other functions they are responsible separate from each other.

Rear Bolt

Rear Bolt Plug

Houses the Rear Bolt Plug, and partially the Bolt Handle.
When marker is cocked, the Rear Bolt is unable to move forward since the sear is applying a constant force against at the groove on the bottom side of the Rear Bolt.
Connects with the Linkage Arm which will then link the Rear Bolt with the Front Bolt; these components will then always move if the other is moved.
When released from cocked position, the Rear Bolt’s flat, circular side will strike the valve, which will in turn allow pressurize gas to be released.

Houses the Drive Spring, Guide Pin(if Drive Spring is completely compressed), and partially the Bolt Handle(more so than the Rear Bolt).
During the action of being cocked, it guides the Drive Spring to compress in a linear manner (the Guide Pin helps by ensuring it remains straight on the other end).

Overall, the Real Bolt and Plug are the location where other components meet to prepare the marker to fire. These two components are vital to ensuring the cocked position is maintained and potential energy in the spring is readily available to be transferred.

Component Form

In general, the Rear Bolt and Rear Bolt plug can be considered partially hollow cylinders, but the other features of these components are essential to their individual functions and interaction between other components:

Rear Bolt Features

Rear Bolt Plug Features

Entirely made of Steel, with a polished smooth surface; post-processing to ensure it fits inside of casing
Symmetric along its top side, lengthwise
Referencing the picture above, the left side outside diameter(OD)/height is and maintains that diameter for a length of X inches. The remainder of the Rear Bolt’s OD/height is 31/32 which is maintained for a length of X inches. The total length is 2.125 inches.
7/8 inches from the right side, there’s a notch on the bottom that is ¼ inches long, 1/8 inches deep and ¼ inches wide. This notch serves the purpose of allowing the Sear to hold the Rear Bolt when being cocked.
At the bottom of the right side there’s a slanted plane that last for a length of 11/32 inches. The slanted surface starts from the right at side at a height of about 1/16 inches with angle of 12 degrees. If a linear cut taken out a cylinder, the resulting plane will resemble parabolic in nature if viewed from the top. This plane serves to allows the Sear to gently change its position when the Rear Bolt is completely forward, rather than abruptly changing.
The Rear Bolt is partially hollow with an inner-diameter (ID) beginning at 21/32 and changing to accommodate the Rear Bolt Plug; the ID of the Rear Bolt at any cross section, should be the same as the OD of the Rear Bolt Plug.
Perpendicular to the notch and slanted plane and ¼ inches from the right end, a hole with a diameter of 3/8 inches goes completely across the Rear Bolt. This hole is used to allow the Bolt Handle to rest partially inside.
There is a small hole at the top with a diameter of 1/8 inches and approximately ¼ inches deep. This hole is where the Linkage Arm is inserted.
Weighs 4.5 ounces

Composed entirely of black plastic with a matte surface finish.
Symmetric vertically in the front side (as seen in the picture above) and its side, if rotated 90 degrees.
Referencing the picture above, the top portion is distinctively wider than the bottom portion. The top portion’s main OD is 5/8 inches and is about 1.25 inches long; while the bottom portion’s OD is 7/16 Inches and ¾ inches long. Total Length is 2 inches.
The top portion can be considered geometrically diverse, since there is a distinct change in diameter with accordance to a certain design. From the OD, the diameter decreases to ½ inches. Also, there is a 3/8 inches diameter hole that goes horizontally across 7/16 inches from the top.
The product is partially hollow with a circular opening with ¼ inches diameter in the top portion, which is maintained for about X inches; at that point it is completely solid/filled again.
The bottom portion is relatively simple, with a consistent diameter until 1/8 inches before the bottom side. At that point its diameter decreases to a point.
Weighs 0.24 ounces

From the information above, the components’ geometry and attributes have a high correlation with the nearby components in the product. The Rear Bolt’s bottom side is consistently interacting with the Sear, the top half is in connection with the Linkage Arm, the larger OD is in contact with the Marker Casing innards, and the left side will have to fit inside the right end of the Power Tube and strike a small pin with great force. The Rear Bolt Plug is continually resting inside the Rear Bolt and deals with varying levels of spring force depending if the Drive Spring is in compression. Also, both components support the Bolt Handle. This reliance on very specific, purposeful geometry requires the materials used to maintain and support any reactions that occur during product use; steel suits the Rear Bolt and Plastic suits the Rear Bolt Plug for these reasons. The materials used have adequate durability and resistance to deforming after constant use. These materials are also industry standards and widely available, so acquiring exotic alloys or polymers to support these functions would not be necessary. Appearance-wise, in order to maintain the simple and straightforward theme, neutral and natural colors were the best decision for these components, since other colors would add cost to the production process. While for both cases the surface finish serves no aesthetic purpose, the outside of the Rear Bolt will always be interacting with the Marker Casing, thus a surface with relatively low coefficients of friction would be required to eliminate non-conservative forces.

Manufacturing Methods

While geometry of each component is not simple, the manufacturing process that were used, die casting and injection molding, easily accommodates single piece, small parts that only require a basic surface finish. However, with consideration to factor friction between the Rear Bolt and the Marker casing, additional post-processing would be needed to create a proper surface finish. Also, the reason there are a Rear Bolt and Rear Bolt Plug is the fact that using metal (which is more expensive than plastic) just to house the Drive Spring is not an economically wise decision, thus having a plastic plug to take place of the inside lower the overall cost needed for the resources; the lower cost would overcome the investment for a simple mold design.

Component Complexity

The component complexity can be considered accordingly :

Material Composition Diversity: A rating of 1, since these components required two different materials among both of them.
Manufacturing Process:A rating of 1, since the manufacturing process is simply casting/molding which only requires a permanent mold and the material to fill that mold.
Energy Interaction:A rating of 3, since the Rear Bolt deals with a high impact force when striking the Valve, and the Rear Bolt Plug withstands spring forces from the Drive Spring.
Geometry:A rating of 3, since the geometry has unique change with functional meaning.
Component Mobility/Movability: A rating of 2, since the components are always moving back and forth within the chamber, but this is monitored by the user and the forces from the Drive Spring.
Component Interaction: A rating of 3, since the components interact with numerous components each in order to complete their functions and help complete other component’s functions.

Applying the formula: Complexity = 0.10(1) + 0.10(1) + 0.25(3) + 0.20(3) + 0.15(2) + 0.20(3) = 2.45

Trigger

Component Function

Trigger

The Trigger’s main function is to provide a means for the user to fire the paintball marker. From an overall system viewpoint, the trigger fires paintballs; from a sub-system viewpoint, the trigger lifts the sear which releases the Rear Bolt (if it’s cocked).

Component Form

the trigger is the stereotypical trigger shape with one curved surface for a trigger finger to interact with. Other features of the trigger are:

Weight of 0.23 ounces
Average Thickness of ¼ inches
The top portion (mostly housed in the casing) starts off at a Length 1.375 inches
Continually getting shorter the farther from the top, the bottom portion (portion available to user) ends at a rounded off corner with a thickness of about 1/16 inches.
Two holes in the upper right (see image) that go through completely, both these holes have a diameter less than inch but greater than those of the Trigger Dowel Pins (1/8 inches Diameter). When inside the casing, the dowel pins act as pivoting point for the trigger; when the user “pull” or squeezes the trigger, the trigger will rotate accordingly about these points.
A bump in the upper left faces downward to prevent the Trigger Spring from being displaced during use.
In order to interact with the Sear, a combination of a spring along with a pin and bracket which secures the spring is used. The right side of the trigger is generally flat; this small spring/bracket system allows the sear to be lifted upwards, rather than pushes by a flat surface.
The spring, bracket, and pin are all made of stainless steel.
The trigger is made of black plastic with a smooth, matte finish.
The portion where the user’s finger will touch is rounder, smoother and wider than rest of trigger. The back side of this portion geometry is altered to make contact with the outside of the casing, which prevents an unnecessary, excessive trigger pull.

From this information, the trigger continues the simple and straightforward theme. There are no additional features or overly-ergonomic features for pulling the trigger. The part which would interact with the user accommodates a single finger. While triggers are known to be made of metal, using this material in this product would have to be a result if a user preference, and would then result in a more expensive part cost. In relation to the components the trigger interacts with, the use of metal for the Dower Pins and Trigger Spring are meant for their resistance to wear, so using metal in the trigger could result in wear after prolonged use; plastics, especially with a matte finish, are not prone to wearing down after constant interactions. If the operating environment is considered, a metal spring could contract or expand depending on the temperature, which could in a slight shift in how the trigger is puller (the trigger may have to be puller further or less than normal); plastic does have these properties and will maintain a consistent trigger pull length. Overall, the trigger is meant to be another component of the Tippmann 98 Custom that is designed to simple and straightforward, which has resulted in a components made of readily available, cheap materials.

Manufacturing Methods

The Trigger is single plastic component with a very small, simple system (spring, pin, and bracket) accompanying it. While the accompanying system’s parts are made from extrusion and rolling, the trigger is made by injection molding. With a small, simple plastic component that requires no drastic curves or thin crevices, injection molding would be the most economical decision if they were to be mass produced. The design mold would be quite inexpensive and simple; basic trigger outline could be applied and consideration to the adjacent components would only need to be considered when designing. Along with designing simply, this trigger needs to only be a basic, stock trigger when offered with this product; the components of the Tippmann 98 Custom usually can be changed to improved, customized versions for the right price. However, supplying the basic plastic trigger would satisfy what is required to carry out the trigger’s function and be cheaper.

Component Complexity

The component complexity can be considered accordingly :

Material Composition Diversity:A rating of 1, since the component is mainly one material but continuously used a small steel system.
Manufacturing Process: A rating of 1, since the component represents a simple case of injection molding, and the small steel system uses others, but they are relatively simple as well.
Energy Interaction: A rating of 3, since the trigger experience several forces; these forces originate from the Dowel Pins, Trigger Spring, user’s trigger pull, and Sear interaction.
Geometry: A rating of 1, the geometry is not a standard geometric shape, but still the standard for a simple trigger that involves a slight consideration to ergonomics.
Component Mobility/Movability: A rating of 1, since the component does move but is a simple restricted action.
Component Interaction: A rating of 3, since the component relies on several other component to function (marker casing, Dowel Pins, Trigger Spring, Safety, and Sear), and consistently interacts with each one.

Applying the formula: Complexity = 0.10(1) + 0.10(1) + 0.25(3) + 0.20(1) + 0.15(1) + 0.20(3) =1.9

Sear

Component Function

Sear

Component Form

Weighs 0.27 ounces.

Manufacturing Methods

Component Complexity

The component complexity can be considered accordingly :

Material Composition Diversity: A rating of
Manufacturing Process: A rating of
Energy Interaction: A rating of
Geometry: A rating of
Component Mobility/Movability: A rating of
Component Interaction: A rating of

Applying the formula: Complexity = 0.10(1) + 0.10(1) + 0.25(3) + 0.20(3) + 0.15(2) + 0.20(3) =

Solid Modeled Assembly

3-D Modeling of Rear Bolt System
Rear Bolt Plug	Rear Bolt

Guide Pin	End Cap

Drive Spring	Rear Bolt Assembly

Using Autodesk Inventor, the Rear Bolt System (consisting of the Rear Bolt, Rear Bolt Plug, End Cap, Guide Pin, and Drive Spring), was modeled in 3-D. Each component, except the spring, was first drawn orthographically by hand by the Project Coordinator and then given to the Designer to convert in to three-dimensional model. The Designer chose Autodesk Inventor due to his experience with the program in drawing 3D models. The Rear Bolt System was chosen to have a better visualization everything right of the valve and what conditions it may be in while the spring might be completely compressed or in its equilibrium state. The transfer of energy from the compressed Drive Spring to the Rear Bolt to the Valve is what allows paintballs to be fired, thus have a better visualization of this process will lead to a better understanding of that particular function.

Engineering Analysis

PDF available if desired:File:2012 Group 28 Analysis.pdf

Design Revisions

After analyzing the components of the marker and determining how they interact with each other at a system and sub-system level, certain design revision can be recommended to improve the performance and/or efficiency of the product.

Hopper System Revision

Removing the current Hopper and Elbow Feed, and replacing it with a cycling feed and hopper system will change several aspects of the marker. With a hopper system that is not entirely gravity fed, rather fed by systematically sorting the balls and cycling them into the chamber at faster rate.

^[1]Cycling Feed and Hopper

Trigger System Revision

Another design change that can be applied to the paintball marker is the trigger group. By removing the mechanical trigger and installing an electronic trigger, the user can switch the rate of fire and fire mode. An economic factor is the same as the hoppers, it will allow people to buy this piece for the marker they own and it will increase the amount of paint used, increasing paint sales. A social factor is that it is an attachment that people look for in a paintball marker. It gives an advantage on the field over people who cannot fire as many rounds. The trigger will require little maintenance other than changing the battery. The performance will increase dramatically.

^[2]Electronic Trigger System

Rear Bolt System Revision

Another design improvement is to make the bolt lighter to reduce recoil and use heavier springs to increase the amount of feet per second the marker shoots. A social factor is that people will want to buy it to make their gun shoot faster. It will also make the gun operate smoother.

^[3]Lightweight, Improved Rear Bolt, Rear Bolt Plug, and Spring

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 <h3> Sear </h3>
 <h5> Component Function</h5>
-<p>[[FILE: 2012 Group 28 Sear.png |200px|thumb|right |Sear]]     </p>
+<p>[[FILE: 2012 Group 28 Sear.png |200px|thumb|right |Sear]]
+</p>
 <h5> Component Form</h5>
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-<li>  </li>
+<li> Weighs 0.27 ounces.</li>
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 <li>  </li>
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 <li>  </li>
-</ul>
+</ul><br>
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 <h5> Manufacturing Methods</h5>
+<p>
+</p>
 <h5> Component Complexity</h5>
 <p> The component complexity can be considered accordingly : <br>
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 [[FILE: 2012 Group 28 Engineering Analyis.png]]
-<p>PDF available if desire:[[File:2012_Group_28_Analysis.pdf]]</p>
+<p>PDF available if desired:[[File:2012_Group_28_Analysis.pdf]]</p>
 <h2>Design Revisions</h2>

Group 28 - Gate 3 - Product Analysis - 2012

Revision as of 03:15, 18 November 2012

Contents

Main Page

Purpose

Coordination Review

Cause for Corrective Action

Product Evaluation

Component Summary

Product Analysis

Measuring Component Complexity

Hopper

Component Function

Component Form

Manufacturing Methods

Component Complexity

Feed Elbow

Component Function

Component Form

Manufacturing Methods

Component Complexity

Marker Casing (Custom Receiver Left & Right)

Component Function

Component Form

Manufacturing Methods

Component Complexity

Rear Bolt & Rear Bolt Plug

Component Function

Component Form

Manufacturing Methods

Component Complexity

Trigger

Component Function

Component Form

Manufacturing Methods

Component Complexity

Sear

Component Function

Component Form

Manufacturing Methods

Component Complexity

Solid Modeled Assembly

Engineering Analysis

Design Revisions

Hopper System Revision

Trigger System Revision

Rear Bolt System Revision

References

Views

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