Manufacturing/Construction

Manufacturing / Construction Outline

The manufacturing portion of this project is relatively basic. The framing material that was chosen as the basis of the entire frame is 1" x 1" T Slott Framing extrusion. The reason for this choice was for its ease of assembly and basic need for machining. There is no drilling involved in this material because it is designed to have special brackets used that allow it to be fastened together. Along with its ease of manufacturing and building, a history of using the same material in FIRST Robotics will cut the building time down by a large margin as well.

The majority of this projects manufacturing is using a Miter Saw to cut the framing extrusion to length. This will only take about 2 hours to cut every part of framing material required for the frame, and the tow bar portion of the project.

There are a couple of parts that will require a little more manufacturing time. The Tow bar attachment will require the use of a Milling Machine to create the nose wheel attachment pieces that are on the ends of the tow bar assembly. This process will take approximately 3 hours.

In order for the pneumatic wheels to fit on the drive shaft, which was re designed to allow for the stresses from the worm and worm gear, a hub will need to be manufactured. After a few hours of research to find a solution to this problem, it was found that there are no 3/4" wheel hubs for the wheels that are going to be bought, so 3 hubs will need to be manufactured. This will involve using a lathe to cut material to correct diameter, milling out the center, and adding a key way. The final portion will be making sure the fastener holes are centered around the part. This will take approximately 4 hours.

That is all of the manufacturing this project requires. the rest of the project will be building the device. There are many different brackets that are required for this project, and all of them are to be bought online. Once they are all delivered, the building portion of this project can be started, and in all that should take approximately 10 hrs.

More details on the manufacturing portion of this project can be found in the full report of this project. A link to the report can be found on the Home page.

T Slot Framing Manufacturing

The T Slot Framing portion of this project went without a hitch. This process was done over the time period of two days. The first day went as planned, using the miter saw, the majority of cuts were done (at the time it was the total amount planned with the material obtained). The second day, using the material left over, more cuts were made to create the tow bar. The miter saw was not available at the time, so the band saw was used, and this went much faster than the first day.

Tow Bar Attachment Manufacturing

For the tow bar attachment part, the entire part was made using a milling machine. The first step was to face the end of the raw material in order to zero out the location, and from there, drilling the 4 fastener holes. The second step was was to cut the material to length, and this as done using the band saw. After the part is cut, the groove in the center can be added. This was done by drilling out a center hole, and using the mill to finish creating the groove in the center of the device. Finally, a chamfer was put on all corners of the part for weight reduction. You can see the video and pictures below to see the process.

Pictures / Video

Wheel Hub Manufacturing

These parts are currently being manufactured, and this portion of the website will be updated when its complete, along with pictures. **************

Pictures ********

Device Construction

The majority of parts for this project have been bought online. These include fasteners, brackets, wheels, shafts, bearings, etc, and there have been a lot of each. Because of this, this project has a huge construction phase. Construction of this project has taken much more energy than originally expected. What was created in Solidworks seemed like it would be easy to put together, but in reality, so much has been much tighter than expected, meaning getting everything to fit with each other is not easy.

This has been especially true for the frame / drive train. The most frustrating portions is when pieces you have already put together have to be taken apart to add another bracket or fastener. Because the T Slot Framing uses grooves and the nuts slide in them, if you don't have the number of nuts already in place, and continue assembly, you will need to take it apart to be able to put another bracket on. This has been done at least 10 times already on just the frame / drive train. This project also added a bunch more time than originally allotted to the project. With all of this however, it has been a good learning experience, and one that will prove very useful in the future. It has hammered home the idea that stuff you design in solid works, must be easy to put together.

For the actual tow bar portion of the build, it was very straight forward and easy. Only being created out of 12 parts with nothing truly overlapping made it the fastest portion of the construction phase.

You can find pictures of all the assembly of this project below.

Pictures:

Devon Tandberg

General Aviation Modular Electric Tow Bar

2019-2020 CWU Senior Project