Ideal Harmonic Transformer

pinshape

I was working on an "Analog Sine/Cosine Calculating Machine", but then I discovered the actual name for this device, which I really love. It's a thing to hold, enjoy turning the crank, and look at. If you can't find your calculator and need to know the sine or cosine of an angle quickly, you can dial in the angle and read off the Scotch Yokes. It also works in reverse. I'm planning to paint one up, hang it on my wall, and use it to help explain Trig to my kids. I have built and assembled one. This was initially going to be a simple design to help me learn Alibre, but Simple got lost somewhere along the way. I'm thinking about adding a paper feed and pencil holder, so I can plot with it. Here are two prototype versions, where I worked out the mechanical details. You can read more about them here, along with notes on why I made my own printed screws: http://swampcastle.blogspot.com/2011/06/sincos-prototypes.html I also added photos of some now-funny-looking prototypes that helped me get the design to where it is today. There are various other articles about this project on my blog: http://swampcastle.blogspot.com/. If you don't have a printer, or want the parts in different materials, find them here: http://www.shapeways.com/shops/swampcastle harmonic-transformerstl-mm.zip contains the whole set. If the file name starts with "print1", print one copy; if it starts with "print2_", print two copies. The "alternate" file is a one-piece version of the yoke, and replaces the yoke-T and yoke-extend files. This eliminates the need for glue, but it's 11 inches x 4.75 inches, so needs a large printer. harmonic-transformer_alibre.zip contains all of the Alibre design files. I included a txt file with the names of Alibre files, listed under the name of the stl file that they appear in. You'll need a T15 Torx screwdriver and some glue. I use an Up! printer, which has a 5"x5"x5" printing bed. On the Up!, all bolts and pins need to be printed with fill=solid and quality=fine to provide sufficient torsional strength. Other components may be printed with the default settings of fill=loose and quality=normal. All fasteners are in one file for convenience. File updates: 6/12/2011 9:54 pm, Central: I replaced all files with higher resolution versions. Added Alibre design files. 6/24/2011 Replaced fastener file, giving them a 10 degree tilt on the printer, to make them stronger (thanks for the suggestion, TeamTeamUSA). Added alternate one-piece version of the yoke.