This instance of the Nerdy Derby Race Track is a derivative of the Nerdy Derby project as found at http://nerdyderby.com. Their most excellent work was an inspiration to creating this one.
As stated on the Nerdy Derby website, "The Nerdy Derby is a no-rules* miniature car building and racing competition inspired by the Cub Scouts' Pinewood Derby. With a larger, more undulating track and no restrictions on the size of the cars or materials participants can use, the Nerdy Derby rewards creativity, cleverness and ingenuity."
The work represented by these files is intended to help others create their own tracks and may cause more harm than help. Verify, recheck and then recheck again everything before you use these files.
The original design came in a reduced scale as a PDF file. The design was re-implemented in Autodesk Inventor with nd.iam being the primary assembly file. The nd-NUMBER.ipt and nd-LETTER.ipt represent the individual inside and outside track segments as starting with the finish line.
The nd-NUMBER.dxf and nd-LETTER.dxf files are the faces of track segments needed by VCarve Pro to setup the tool path for a ShopBot Alpha to cut the segments from 3/4" plywood.
The nd-NUMBER*.crv and nd-LETTER*.crv files are the VCarve Pro files used to generate the nd-NUMBER*.sbp and nd-LETTER*.sbp ShopBot files.
The ShopBot files may or may not work for you. Ensure that you've verified them before starting them on a ShopBot. If needed, there should be enough detail in the other files to create the needed ShopBot files for your installation.
The track*.skp files were an early attempt to create the track segments using SketchUp. But since Sketchup's circles and curves are segmented lines, this effort was abandonded and Inventor was used instead.
The curved segments for the track were cut out on a ShopBot Alpha useing 3 pieces of 3/4" plywood. This work took approximately 8 hours of ShopBot time.
The straight segments were cut out on a table saw using 2 pieces of 3/4" plywood along with the left over piece from the curvd segments. This was approximately 4 hours of work.
Glue up of the segments took approximately 5 hours. First assembly took an additional hour. Standing the track took another 2 hours.
There's another 2 or 3 hours used to buy supplies, transport materials, etc.
The design work consumed on the order of 6 hours.
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Cutting the straight segments on a tablesaw saved ShopBot time but cost sanding time since the cuts were not a precise as would have been on the ShopBot.
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The segments should have been numbered / lettered and a toolpath created to carve the numbers / letters into the segments on the ShopBot. By not doing this, some amount of time was used to just organize the segments so that the correct ones were glued together.
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Don't forget to zero the z axis. The ShopBot doesn't know and will happily carve into your material and possibly break bits and parts.
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In VCarve Pro, set up 2 tabs per piece, especially for longer pieces.
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The default 1/8" tab is too shallow for plywood. Use 1/4" tabs.
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Ensure that the tabs aren't being cut by a previous or following pass.
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Make sure tabs aren't connected to other pieces that are cut out.
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The ShopBot files were exported from VCarve Pro as Shopbot alpha w/ speed.