Group 5 - Two Power Sanders
For the MAE 277 reverse engineering project, our group was given two electric powered RYOBI corner sanders (Model #’s P400 & CFS1502). One of the sanders is powered by an electric cord and the other is battery-powered. Throughout the semester, we will be dissecting and analyzing the components that make these two products work. We will then compare the different results for the two sanders to figure out which one is more efficient than the other.
The difficulty scale is based on a 1 through 5 scale:
- Only use of hands needed, requires little/no* difficulty (no tools required)
- Only use of hands needed, requires some* difficulty (no tools required)
- Only use of hands needed, requires high* difficulty (no tools required)
- Requires use of single tool, but requires little/no* difficulty.
- Requires use of single tool, but requires some* difficulty.
- little/no difficulty- requires less than 5 minutes to complete
- some difficulty- requires between 5-10 minutes to complete
- high difficulty- requires more than 10 minutes to complete
RYOBI Battery-Powered Corner Sander
|1||Place the electric motor and switch assembly into the housing so that the gear is placed into the lube. This part is fitted into the casing. The wires should be tucked into the outer parts of the housing so they will not be pinched when it is put back together.||2||Hands|
|2||Place the black switch in it's fitted housing next to the motor. Then place the yellow on/off button over the black switch.||2||Hands|
|3||Place the small metal clip against the yellow switch to stabilize the switch.||3||Hands|
|4||Place the gears and bearing with counterweight into its fitted spot in the housing. The gears should now be able to rotate the spindle.||1||Hands|
|5||Place the two white connectors (cushion supports) into the housing. The smaller one fits in below the switch assembly. If looking at the sander with the motor to the top right, the larger connector will be placed about an inch to the left of the gears in it's fitted spot.||1||Hands|
|6||Slide the other casing onto the casing with the motor, gears, and switch assembly. It should match up so that connectors go into their fitted spots. The connectors should now be seen on the bottom of the sander.||2||Hands|
|7||There are eleven Phillips head screws that need to be screwed onto the outer casing. There are designated holes for the screws, and they are the only holes on the sander.||5||Phillips head #2 screw-driver|
|8||Snap the Velcro pad housing onto the bottom of the sander. It snaps on using the connectors. Then screw on the Velcro pad housing using the four screws||4||Phillips head #2 screw-driver|
|9||There are five Phillips head screws that need to screw the sand paper Velcro pad onto the sander.||4||Phillips head #2 screw-driver|
RYOBI Corner Sander
|1||Slide the field assembly over the armature assembly. The wires for the switch should be on the opposite side of the vacuum fan as seen in the picture.||1||Hands|
|2||Attach the switch to the field assembly. This is done by connecting it to the fitted connector of the red wire.||1||Hands|
|3||Connect the black wire coming from the power supply cord to the switch.||1||Hands|
|4||Place one brush into the connector coming from the white cord of the power supply. Place the other brush into the connector coming from the black cord of the field assembly.||1||Hands|
|5||Everything assembled thus far will fit onto the casing. The field assembly has a fitted spot in the center of the casing, everything else attached will fall into it\'s fitted spot.||2||Hands|
|6||The orange on/off switch lays in next to the switch assembly||1||Hands|
|7||The black fan baffle fits in over the sand vacuum. The curved edges will fit onto the housing properly.||1||Hands|
|8||Place the two white connectors (cushion supports) into the housing. The smaller one fits in below the switch assembly. If looking at the sander with the motor to the top right, the larger connector will be placed about an half an inch to the left of the field assembly in it\'s fitted spot.||1||Hands|
|9||Place the second half of the housing onto the connectors. Wires must be placed in designated areas. There are teeth that will catch the wires to keep them in place.||3||Hands|
|10||Screw in the second half of the housing onto the other half. There are 4 screws that should be used to do this.||4||Phillips Head #2 screw-driver|
|11||Screw the two cord clamp screws over the cord where it meets the sander.||4||Phillips Head #2 screw-driver|
|12||Screw in both of the internal screws to connect both casings. These screws are located underneath where the grip will be.||4||Phillips Head #2 screw-driver|
|13||Place the grip on top of the sander. Fasten the three top cover screws.||4||Phillips Head #2 screw-driver|
|14||Place the velcro pad housing onto the bottom of the sander and use the 4 velcro pad housing screws to fasten it.||4||Phillips Head #2 screw-driver|
|15||Place the velcro pad onto the velcro pad housing and use 5 of the velcro pad housing screws to fasten it onto the velcro pad housing.||4||Phillips Head #2 screw-driver|
|16||Fit the dust bag over the vacuum exhaust coming out the back of the sander as seen in the picture.||1||Hands|
In this part of our project we reassembled our products. Overall it was a fairly simple process for us seeing that we have done it a few times. We have done it a few times because to keep track of parts we always reassemble it after taking it apart.
When doing the assembly process our group could only get one sander and not the other to run just as well as they had when our group received them. The battery powered sander runs just as good as it had when we received them. This is because there is not much to go wrong with the sander as long as all of the wires and cords are in good condition. As for the AC sander, the leads broke during reassembly so it will not work. The leads were made of graphite which is not very strong. If new leads are purchased, the sander will be back to working condition.
The dis-assembly and reassembly used the same tools. These tools include a Phillips #2 head screw driver and hands. There were some differences between the two processes, mainly in difficulty. Step 3 of the battery-powered sander was more difficult because it takes an exact amount of force to get the clip in the right way. This is different than in the dis-assembly, where the clip is just taken off. Also, step 6 of the battery-powered sander was more difficult because once again, there was a very particular way that the clip was to be placed where in the dis-assembly clip was just taken out.
After reassembly of the sanders, we ran into a couple of difficulties, all of which could be improved upon at the product level. When reassembling the AC sander, we ran into problems while trying to place all of the components in together and fitting the housing on. We happened to break the brush tips while doing this maneuver. The tips were made of some type of carbon material much like the tip of your pencil (possibly graphite) and was very brittle. If a stronger material such as metal was used, this problem would be avoided and the tips wouldn’t break. Another improvement we would recommend is to make more room for the electric wire to be placed within the housing of the AC sander. It took many tries to get the fitting of this sander correct because the wires didn’t have much space to be placed. We would recommend that the housing have a little bit more “play” area for the wires so that reassembly and maintenance would be more straight forward (much like the battery- powered sander). If more tolerance was allowed for the wires to fit in the sander the reassembly would have been much simpler. The only downside to adding this additional space would be that more material would be used and in turn a greater cost to the manufacturer. Considering this alternative's added cost, we still feel that it is worth the small increase in price.