Goddard Clamp

grabcad

Simple and printable 2 piece clamp. No supports needed. After looking at some of the other models in this contest, I just felt like I'd like to try somethings simple, printable, and just works. I saw the video in the challenges description, showing the printer actually in use. Having a lot of experience with 3D printing, I know that unless the printer is really finely tuned, printing in thin layers and has all the temperature and speed settings just right, you don't always get what you designed. At least as far as tolerances go. That's why I just opted for a simple slide fit tension style clamp. Having printed miles and miles worth of filament, I've found that the simpler the design can be and still work, the more successful each print will be. I also took into consideration strength of the printing orientation. The entire model is printed in such a way that the XY (strongest plane) runs the full length of the part. (Z). I have been very busy with design work so I had to put this off a little longer than I would have liked to. If I had to change anything, I might adjust the track so that the centering hole is in the center of the channel. I was really trying to stay within the 1" cross section boundaries, or else I could have strengthened/thickened it up some. My first Print turned out pretty tight, so I added some tolerance. The prints now feel really good. At least on my machine. It's impossible to say weather or not the tolerances will be exact for the ISS printer, but those tolerances can be easily adjusted due to the simple design. I uploaded a quick (albeit poor quality) video of it in action. It's really very simple. The clamp goes around the rail, and the channel is slid into place and tensions the clamp to the rail. Prints were done at .25mm layer heights (to immulate a really rough and less than ideal print) Print times were 3 HR 35 minutes but that's on my machine, the ISS machine will be different as I don't know the speed or acceleration values, travel speed, etc... Rail Piece is designed so that it is printed in a slightly pre-opened configuration allowing easier installation around rail. Tolerances are set so tension is applied once the track piece is slid on, again the tolerances can be adjusted depending on actual print dimensions. I did print a test rail and sand it down until it measure right at the specified values listed before testing the fit. It has great holding force. The design is simple and functional. The channel is nice and durable. It's very easy to use. There is no (or very little) post process. The print orientation is optimal for the strongest possible part for its size. I feel that all of these make fore a good design.