reverse engineering project - carleton university - 2009

ECOR 1010 – INTRODUCTION TO ENGINEERING

REVERSE ENGINEERING PROJECT

“PENCIL LIFE EXTENDER”

GROUP NUMBER – A2-16

To

Project TA: Jim Robinson

E-mail: [email protected]

Lab section: A2

Room: ME 2256

From

Group members:

Udendra Ganegama Arachchi - 100806424 - [email protected] Donoghue

Shawn

Date: November 27th 2009

mailto:[email protected]



Table content

1. Title page --------------------------------------------------------------------------------------------------Pg.1

2. Abstract ---------------------------------------------------------------------------------------------------Pg.3

3. Report------------------------------------------------------------------------------------------------Pg.4 to 5

4. Appendices------------------------------------------------------------------------------------------Pg.6 to 71.0 – Pro/E rendered solid model

2.0 - IntelliCad



Abstract

The Pencil Life-Extender (hereby referred to as the PLE) is an improvement on an existing design of pencil holder, whose purpose is to increase the usable length of a pencil which has become too short to grip effectively. Designs currently on the market are entirely hollow, short and are limited in application to the standard hexagonal pencil. The PLE is composed of two barrels of differing diameters, allowing for application to both standard and ‘jumbo’ pencil sizes and their circular shape allows for use with both hexagonal and stylized pencils. Both barrels are sized to firmly hold the appropriate pencil inside and contain notched sides to incorporate sliding mechanisms to support varying pencil lengths. The barrels are separated by a solid bridge that provides structural support to the part and allows for the use of softer, recyclable plastics while maintaining integrity and rigidity. The PLE also doubles as a storage unit for used pencils, allowing them to be inverted to protect the brittle graphite then easily removed for use using the adjustable slider. The new pen clip on the exterior adds mobility and ensures that the PLE is always accessible and on hand.



Introduction:

The limitation of a typical pencil is the fact that it becomes unusable after its length decreases a below a certain point. There are various tools in the market available to extend the life of a pencil. The objective of this project is to design and improve on the commercially available pencil extender, which will hereby be named the Pencil Life Extender (PLE).

Method:

Defects in the current market product were analysed and improvements were made to rectify them. Following are the major defects and suggested improvements:

1. The current design just a plain tube; therefore we plan to incorporate a clip for increased portability.

2. Only the standard pencil size complied with current designs, so the improved design will have the capability of storing multiple types of pencil.

3.4.

A prototype of the PLE was created to test optimum ergonomics using Pro/E (Appendix 1.0).

Lastly, an environmentally friendly production method will be explored to successfully integrate the PLE into the market. IntelliCad working drawings (Appendix 2.0) were created to aid the manufacturer during production.

Results and Discussion:

IntelliCad

Pro/E rendered solid model (Appendix 1.0)The prototype was a scaled up by relative to the original versionLength: Ovarall the product had a good ergonomic feel.



Manufacturing methodsThe chosen material for our product was Polyethylene Terephthalate (PET) due to its strength, ease of recyclability (thus environmentally friendly) and fairly low density (implying a lighter weight).

The methods considered for the manufacture of the PLE were compression moulding, blow moulding, and injection moulding.

Compression moulding involves the preheating of the plastic pellets into the mould and a hydraulically driven plunger compresses the plastic against the walls. Afterwards a clip detaches the finished product.

Injection molding is the most viable solution for creating the PLE as it is both cost effective in the long run (initial costs may be high) and time efficient.

PET in pellets (size ranging from 1 to 700oz) form is fed into a heated barrel. A screw type plunger forces the pellets into a heated chamber where they melted. The plunger causes the plastic though a nozzle which fills a cold PLE (cooled by water) mould. The plastic in the mould cools instantaneously. The finished mould may be machine polished to remove any inconsistencies on the surface.

Conclusions:

The PLE is an overall an improvement to the pencil holders in the market.

References and AcknowledgementsCompression molding – “Wikipedia”; http://en.wikipedia.org/wiki/Compression_moldingTodd, Robert H., Dell K. Allen, and Leo Alting. Manufacturing Processes Reference Guide. New York: Industrial P, Incorporated, 1993.

Blow moldingInjection molding – “Wikipedia”; http://en.wikipedia.org/wiki/Injection_molding

http://en.wikipedia.org/wiki/Compression_molding



- Material and Manufacturing processes: These two topics may require some research online, in textbooks or in the library, etc. You need to be as detailed as possible. Saying your part is made from plastic or metal is not sufficient. There are two main ways of approaching this: find out exactly what your object (or a similar object) is made of from your research or research the different materials and find out what characteristics most closely match your part. (i.e. if your part is steel, look at things like corrosion resistance, strength, toughness, magnetism, conductivity, ductility, fatigue resistance, etc. to determine what your part is made of.). Similarly, for manufacturing process, either find out exactly how your part (or a similar part) is made, or research different manufacturing processes and determine which one best suits your object. It may be a combination of processes.

Appendices1.0 - Pro/E rendered solid model



2.0 – IntelliCad working drawings

reverse engineering project - carleton university - 2009

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