Candy
CANDY - SIMONE
PROMPT
Enhance and continue to develop modeling and design skills via CAD-CAM CNC machining by creating a desktop object using SolidWorks for surface and solid modeling, SolidCAM for programming toolpaths, and a Haas Mini Mill along with a Prototrak 3-axis for machining.
Process – Inspiration
My desk object came from my findings of a rare late 1930s concept car. I am amazed at the styling of these 1920s and 1930s classic cars in general and was awe-struck by the styling of this Duesenberg Coupe Simone. I opted to do a 3D silhouette of this car as I thought the curves of this design fit the candy prompt very well.
Process – Design and CAD development
Designing in SolidWorks Surfacing went to the 18th revision as I tweaked and changed various surfaces to avoid undercuts, took consideration to the mounting holes positions and tool paths during each setup and operation, while still paying homage to the original overall styling of the vehicle. The process involved first importing isometric images to SolidWorks, then modeling based on the images surface by surface, and finally mirroring.
Process – Making - Setup
The setup for the operations involved a provided steel fixture plate located against a stop in the vice with the x-y zeros set at the top left-hand corner. I created another squarish fixture plate to prevent accidental marring of the previously mentioned fixture plate and another 6061-T6 aluminum bar stock. Op 1 would involve roughing and finishing the bottom portion the object and creating the fixturing holes. Op 2 involves flipping the part over, and roughing and finishing the remaining 80% of the top portion of the model’s depth.
Process – MAKING - MACHINING
For both ops, a ½” square endmill was used for roughing and a ¼” ball endmill was used for finishing. Both tools were going at 6000 RPM with a feed rate of 50 IPM.
Process – Making - Sanding and POLISHING
Quite a few scallops were still present even after the finish passes. Initial sanding started at 80 grit and moved up to 220 grit. Along with a Dremel and some router bit attachments, I began to achieve my desired outcome.
Process – Making - Sanding and POLISHING ii
There was still a very visible transition line apparent due to the setup between op1 and op2 when the part was flipped over. This was probably due to some slop on the fixturing holes or an offset issue during setup. A metal disc sander and a file were used to alleviate this issue along with some other stark features. The 2nd stage of sanding involved going through 6 grades of sandpaper (240, 320, 400, 600, 1200, and 1500 grit) followed by some metal polish using a rag.
Process – Making - stand
The stand was made from cedar that was planed at an angle on all four sides to point the viewer to the object. The word “Simone” was laser engraved into the wood. I took advantage of the previous fixturing holes on the base of the object used during the operations as attachment points to the stand.
learning and takeaways
When aluminum is clear anodized, the previous polished surfaces becomes dull again. I debated on whether to have it anodized, but in the end I opted for the protection instead of the mirror finish.
I would have adjusted the depth of cut a bit more, especially at where certain surfaces met, in order to reduce the sanding and polishing time. It was incredibly fun to machine on a CNC mill again, this time at Penn, and to machine an object for the first time that was more sculptural rather than functional was pretty neat. The candy will be sitting on my table/workbench for a long time. Who knows when I’ll get a chance to do something so personal like this again.