Modeling

Get to measuring (with calipers).

Do not take the part home.

Consider all the specifics:

• How do you model the spherical indents in the cylinder?

• How do you check the angle of the chamfer?

• Making this part using a revolve would be fastest, but then how do you handle the rectangular prism on the narrow end?

• Make sure the holes are the correct thread and the correct depth.

• What is the angle between the square shaft and the spherical indents?

• What is the angle between the square shaft and the three holes?

• How can you check that the depth of your spherical indents is roughly correct?

• What is the diameter of the smallest part of the shaft compared to the square part of the shaft?

Drawing

Create a drawing of the part. This includes all the necessary views for clarity.

For ease of tolerancing purposes, don’t worry about tolerancing the depth of the threaded holes or the spherical indents.

It is highly encouraged to print your drawings and exchange with a friend to critique each other’s work. This is how it typically works in business, the drawings are created by one party and verified by another. Once you think you are done, let the MECE Lead know, and they can send you the corresponding correct drawing or provide a paper copy so you can check your work.

Design an Interfacing Part

Now that you have a part in CAD and a corresponding drawing, it’s time to create your first custom design.

Design a 3D printable box that acts as a protective housing for the funky shaft. The box should have a top and bottom that have a hinge of some fashion. We’d recommend using common hardware for the hinge, but you can use a compliant mechanism or another method if you’d like. The box needs to stay closed when inverted, so you could design a latch of some kind, or you could use magnetic tape of some sort. The box should fit the profile of the funky shaft closely enough to not rattle aggressively.

Hints for 3D Printing Design:

1.      Make sure if your part needs to be relatively strong, that the part must be printed so the load will be applied in the x or y axis. This is because the z axis is weak in a 3D printed part, as the layers are only held together with adhesion, while the layers in X and Y are continuous polymers.

2.      Try to avoid overhangs to minimize support material. Support material is annoying to deal with and often requires postprocessing of the part.

3.      Tolerances on 3D printers are not very accurate, especially for holes. This is because of the shrinking and expanding of the plastic as it’s deposited layer by layer. Especially for holes on the smaller side (<1”) it is recommended that you increase that dimension by 5-10%.

Review your design with Adam, Byron, or Szymon (ABS). After making any necessary changes/updates, send the STL to Szymon for 3D printing. Once you have the part in hand, make sure it works, and review again with someone from ABS. 

Modeling

Take the assembly apart and get to measuring (with calipers).

Please rebuild the assembly before leaving the meeting.

Do not take the parts home.

Please consider all the specifics:

• The fillets on the corners of the acrylic

• The threading in the acrylic for the screws (this will not be a predefined screw in SolidWorks, so pick a standard machine screw threading that would roughly fit the size of the hole).

• All the countersinks and extruded profiles involved in the screw holes (the depth of these dimensions will be less accurate and that is okay).

• The holes in the bottom half of the acrylic. These are crucial for thermals.

• The materials of the components, and the transparency of the acrylic.

• The decal on the bottom half of the acrylic. It says GE Vernova on the actual part, but you should have fun with it! Depicted is Ritchie; however, you could put a meme or a fellow EVT member on there, as long as you have a decal.

• The mates in the assembly itself! There will be seven parts to this assembly. Two pieces of acrylic, the charging coil, and four screws. Screw 3D models can be obtained from McMaster Carr. Find the screw you want and download the SolidWorks file accordingly. Try to employ best modeling practices. For instance, since the pocket for the charging coil is centered in the width of the acrylic, you should use a centerline to dimension off of, that way, if we want to change the width of the acrylic plates in the future, we can change one number instead of changing the width, and then the distance from the side of the plate to the pocket.

• Please DO NOT worry about modeling the charging coil electronics. The coil itself, the resistors, and diodes are not crucial for our geometry. Take the general profile of the charging coil instead. The PCB thickness, the coil thickness, the geometry of the USB C port, etc.

Drawing

Create a drawing of the assembly. This includes all the necessary views for the acrylic pieces and the charging coil, a BOM for the parts, etc.

For ease of tolerancing purposes, only put tolerances on the pockets in the acrylic pieces meant for the charging coil. The rest of the tolerances don’t really matter, since they don’t interface with anything (except for the screws). It is highly encouraged to print your drawings and exchange with a friend to critique each other’s work. This is how it typically works in business, the drawings are created by one party and verified by another. Once you think you are done, let Szymon know, and he can send you the corresponding correct drawing or provide a paper copy so you can check your work.

Design an Interfacing Part

Now that you have a part in CAD and a corresponding drawing, it’s time to create your first custom design.

Design a 3D printable part that houses the charging coil and can hold your phone on an angle while it is charging. Ensure that the angle can be adjusted. If you would like to keep the entire assembly after you are done, please base the design off a charging coil or wireless charging puck you have at home (since we don’t have multiples of these base design parts).

Hints for 3D Printing Design:

1.      Make sure if your part needs to be relatively strong, that the part must be printed so the load will be applied in the x or y axis. This is because the z axis is weak in a 3D printed part, as the layers are only held together with adhesion, while the layers in X and Y are continuous polymers.

2.      Try to avoid overhangs to minimize support material. Support material is annoying to deal with and often requires postprocessing of the part.

3.      Tolerances on 3D printers are not very accurate, especially for holes. This is because of the shrinking and expanding of the plastic as it’s deposited layer by layer. Especially for holes on the smaller side (<1”) it is recommended that you increase that dimension by 5-10%.

Review your design with Adam, Byron, or Szymon (ABS). After making any necessary changes/updates, send the STL to the MECE lead for 3D printing. Once you have the part in hand, make sure it works, and review it again with someone from ABS. 

Modeling

Take the assembly apart and get to measuring (with calipers).

Please rebuild the assembly before leaving the meeting.

Do not take the parts home.

Please do not remove the O-rings within the air cylinder.

If there are many individuals working on the air cylinder, make sure you split up the parts among EVT members. If there are not enough calipers, one person can take measurements and write them down on a quick hand sketch of the part, while the other models the basic geometry. Or, you can take turns measuring the geometry as a two man team!

Consider all the specifics:

1.      The system is designed to be airtight at relatively high pressures (~80psi), therefore any damage to internal seals will stop the cylinder from functioning as intended. Be careful when handling the internals.

2.      Screw 3D models can be obtained from McMaster Carr. Determine the screw size used and download the SolidWorks file accordingly.

3.      The slight chamfers on the holes.

4.      The decals on the sides of the air cylinder. It says Bimba and FLAT-1 on the actual part, but you should have fun with it! You could put a meme or a tiny picture of a fellow EVT member on there, as long as you have a decal.

5.      The materials of the air cylinder differ across the part.

6.      The mates in the assembly. This assembly has 22 parts! Make sure the parts interact correctly so that the piston can extend, along with limits to the motion so it does not decouple from the rest of the assembly.

7.      There are threaded holes in the top and bottom aluminum pieces that are inlets and outlets so the air piston can be activated. Ensure these are modeled to the correct thread and depth.

Drawing

Create a drawing of the assembly. This includes all the necessary views for the aluminum pieces and the piston, a BOM for the parts, etc.

For ease of tolerancing purposes, only put tolerances on the piston and interfacing brass. The rest of the tolerances don’t really matter, since they don’t interface with anything (except for the screws). It is highly encouraged to print your drawings and exchange with a friend to critique each other’s work. This is how it typically works in business, the drawings are created by one party and verified by another. Once you think you are done, let Szymon know, and he can send you the corresponding correct drawing or provide a paper copy so you can check your work.

Designing an Interfacing Part

Now that you have a part in CAD and a corresponding drawing, it’s time to create your first custom design.

Design a 3D printable bracket/mount that attaches the air piston to a 1-2” tube. Ensure that the mount works for the upper and lower range of the tube diameter.

Hints for 3D Printing Design:

1.      Make sure if your part needs to be relatively strong, that the part must be printed so the load will be applied in the x or y axis. This is because the z axis is weak in a 3D printed part, as the layers are only held together with adhesion, while the layers in X and Y are continuous polymers.

2.      Try to avoid overhangs to minimize support material. Support material is annoying to deal with and often requires postprocessing of the part.

3.      Tolerances on 3D printers are not very accurate, especially for holes. This is because of the shrinking and expanding of the plastic as it’s deposited layer by layer. Especially for holes on the smaller side (<1”) it is recommended that you increase that dimension by 5-10%.

Review your design with Adam, Byron, or Szymon (ABS). After making any necessary changes/updates, send the STL to Szymon for 3D printing. Once you have the part in hand, make sure it works, and review again with someone from ABS.