Group 11 - Ryobi Router

Revision as of 22:11, 12 December 2007

This is a Test

Executive Summary

As part of an undergraduate engineering course final project, our team of five students was tasked with reverse engineering a modern hand-held wood router. The procedure was to consist of a complete product dissection including disassembly, reassembly and information documentation. The work effort was divided into phases, each encompassing different procedures within the overall project.

The initial phase consisted of a complete disassembly of the product and accompanying photographs and documentation. This was relatively simple as the unit neatly breaks down to four major components which in turn can be further reduced. Once all components were stripped, identified, and cataloged we turned to the task of analyzing each component while considering various engineering issues relevant to the construction of the item. Once satisfied with the intense scrutiny of each component, the next phase consisting of reassembling the unit was underway. Again, engineering issues such as ergonomics, material performance vs. cost and individual component efficiency were considered with respect to the individual components of the unit. The resulting answers to these issues were documented in the form of the Team's recommendations for improving the product.

Once completely reassembled, the team shifted its efforts to creating a presentation to exhibit its findings. This involved the collection and organization of key information regarding the project and the subsequent development of a PowerPoint presentation. This presentation was to showcase the product itself within the context of engineering in general.

Finally, the last phase of the project involved the production of a technical report containing answers to previously posed questions regarding various aspects of reverse engineering and engineering in general. This report was compiled utilizing the various information collected during the previous phases and was significantly more thorough than the presentation with regard to technical data.

Introduction

Early wood workers exhausted themselves while working with primitive hand tools. Certain tasks were especially difficult and labor intensive and thus required particular endurance and skill. Specifically, the task of hollowing out or “routing” out a section of wood was tedious and involved the use of archaic hand tools such as the hand planar. This device consisted of a narrow blade projecting well beyond its base plate and a broad-based wooden hand plane from which to work the tool. Though the process was tiresome, the tool performed satisfactorily and earned the nickname “Woman’s tooth” due to it’s distinct shape (Wikipedia, 2007).

Fortunately for woodworkers, the emergence of new technologies led to the development of increasingly efficient tools. Shortly after WWI, the first hand-held electric wood routers sprang onto the scene and since have experienced the development of a slue of variant designs.

The subject of our project was a Ryobi P600 laminate trimmer. Though not marketed as a "router" it can be classified as belonging to that family of tools. Its primary function is as a trimmer used in wood working to create intricate grooving and shaping. Its a hand-held, single phase, dual grip unit, and at a mere 2.3 lbs - incredibly portable and versatile. The power house is a an 18 volt DC electric motor with a 26,000 rpm no-load rating which is capable of delivering ample torque necessary for light trimming and routing applications. The light weight of the product is attributed to the almost entirely plastic housing which encases the unit [Ryobi Limited].

The reverse engineering project was conducted by five highly motivated University at Buffalo Mechanical Engineering undergraduates. The team leader of MAE277-Group 11 was John Kostadinov. John organized and planned the work effort as well as oversaw progress of task completion. Next, Tom Consolazio conducted preliminary research as well as developed and delivered the presentation portion of the project. George Stamatros was the project photographer and was instrumental in the disassembly and reassembly phases of the dissection. The third member, Mike Bednarz, gathered crucial data necessary to the production of the report as well as documented various steps of the project. Finally, Anthony Hussak played a key role in collecting and organizing various information necessary for project completion. He also aided the presenter in fact checking and generating an outline for the presentation.

Before Disassembly

As described previously, the router's main function is to create intricate grooving and hollow out sections of material. It's rotating bit is driven by an electric motor which houses a spinning armature. This armature, or rotor, is caused to rotate by an electromagnetic field created by the presence of electricity and magnets (Brain).

Our initial impression of the Ryobi P600 was of a product that might contain numerous small components numbering in the 10-20 rage. However, to our surprise the unit dissembled quite tidily into 2 main components - the motor and housing. This led to our conclusion that the router is essentially an electric motor attached to a spinning bit. In addition, judging by the relatively simple demeanor of the unit we guessed that it was composed of around 4 different materials. In reality, eight different materials are represented within the unit.

The unit can be purchased without a battery as it is a part of Ryobi's "One+" system which is comprised of a suite of tools all of which operate from the same rechargeable battery - which can be purchased separately [Ryobi Limited]. This prevents from purchasing redundant equipment and keeps overall cost down. As such, an operations test could not be performed prior to disassembly. However, an accurate estimation of the tool's operating nature and capacity can be made from the knowledge of routers in general. The rotating bit of a router creates a distinct "whine" which is unique among wood working tools.

During Disassembly

The following steps were taken to disassemble the router:

• First we removed the clip-on cover from the router

• Then four Phillips head screws were removed from the bottom of the wood working sub-base via a Phillips head screwdriver

• Next, the two plastic depth adjustment latches and the attached springs were taken out by hand

• A yellow cap on the top of the unit was removed by hand, thus releasing the strap and the attached clip

• With those parts removed, the blue and yellow casing easily separated from one another

• At this stage, thirteen different components were counted

• Next to be disassembled was the yellow translucent base

• For this, we used a Phillips head screwdriver and the provided 5/16” wrench

• The black painted hex nut was removed first using the wrench

• Then the washer and rectangular spacer slid off by hand

• Finally, the metal clasp was left and this was also able to be removed

• All parts removed thus far were located on the transparent cylindrical section of the unit

• Next we examined the transparent base

• To separate this part from the cylindrical section, we removed four Phillips head screws from the base

• Once this was completed, we had obtaines a fully disassembled router base

• Next in line was the plastic housing which encases the motor and associated hardware, it also gives the router it's distinct shape

• Holding the housing together were eight Phillips head screws

• With the screws out, a simple pinch of the retainer tabs was all that was needed to separate the twin housing components

• Inside we found the heart of the operation: the motor

• For fear of compromising the integrity of the unit, we did not disassemble any further

On a scale from 1 to 5, with 1 being easy and 5 being difficult, all of the disassembly steps rated around a 1. There weren't many moving parts that required extensive disassembly and everything that did break down was of basic design making it easy to disassemble. The only tools used were a Phillips head screw driver, and the provided 5/16" wrench.

After Disassembly

Reassembly Process

Final Thoughts