Construction Phase 2¶
Reworking the Flange Connector¶
A problem with my current project is that the flange attachment is not complete built down into the terminal side. Part of it is suspended above the rail, and so the connection is not secure. This is seen here:
I realized that the distance from the motor L-fixation adapter to the center of the motor shaft (as highlighted in red) needs to be the same as the distance from the center of the flange to the flange attachment piece:
This distance was determined by measuring the distance from the rail to the end of the motor shaft and subtracting the radius of the motor, which is a known variable (5.00mm/2 = 2.50mm). The distance turned out to be 28.65mm. I learned a big lesson here, and it’s that I cannot estimate values and put them into my design. I must calculate the unknown values based on what I know, either through looking at data sheets or measuring them myself.
And so I made the corresponding change to my flange attachment file. I also widened the screw holes at the bottom to 4.7mm in diameter. I added 5.0mm to the overall thickness of the attachment in the middle part. The length remains unchanged at 52.5mm.
This is my updated file:
Although one mistake I made was accidentally changing the distance between the two holes for the flange itself. It turned out to be 5mm less than the intended distance, and I had to drill the hole to make it larger.
I had a failed print on my home 3D printer:
I went to my school lab and made the right prints, and constructed the pieces to my project:
As you can see, the motor attachment and the shaft is now straight from left to right:
Hall Effect Sensor Attachment¶
I used an L-bracket to attach the attachment to the bottom-most aluminum rail, using the included black screws that came with the L-bracket attachment bought from Amazon:
For the cap, I inserted 3 wires, each corresponding to a lead on the sensor, into the hole on the cap. Then, the cap is press-fitted onto the corresponding base.
Finally, using store brought magnets, I was able to insert the magnetic field by supergluing a magnet onto the edge of the wheel.
General Assembly¶
In this step, I assembled the rest of the machine, and I first created a diagram that listed out the dimensions of the different parts for the machine:
These parts were then cut. The aluminum rails were cut to the correct lengths using the band saw.
Then, I constructed the rectangular prism behind the wheels to create room for the tube attachment.
I used a level to make sure that the entire structure remains level and stable. When it wasn’t, I undid some of the screws and removed an L-bracket so that it stays secure.
The structure so far is made up of mostly aluminum bars and
Tube Attachment¶
The distance of the tube from the wheels was determined to be around 7 to 10 mm, and the corresponding aluminum bars were cut using the band saw (see General Assembly above).
Screws were screwed into the back rectangular holes of the tube attachment piece, and a long screw was put into the tube attachment front, tightening the tube inside.
Base Assembly¶
I created the wooden base using 4 pieces of wood, and glued them together to form a sturdy rectangular base.
I talked with Mr. Dubick and he said that to save time, I wouldn’t need a triangular piece across the diagonal since I already have a rectangle made of 2 by 4s and it was sturdy enough.
I then assembled the base to the base of the machine using the black L-brackets and wood screws. There were also 30 mm sections of aluminum rails that I cut that served as adjuncts to the base of the structure that were attached to the wood:
