User:Crg5149
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Hello! My name is Carson Geib and I decided to join the 3-D Printing class this Spring 2014 semester because I needed a design elective credit and I think additive manufacturing is the future. I hope to learn how to build a 3-D printer, troubleshoot the electronic systems, and manufacture some of the hardware components. So far, I have been able to refurbish and manufacture new hot tips.
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References
Hot Tips: Manufacturing and Design Challenges
After manufacturing the hot tips, there were some obvious challenges. One of those challenges is the small amount of material left between the inside and outside diameter where the external threads are on the steel cylinder. There has also been an issue with inserting the insulating Teflon in the smaller diameter hole that has dimensions of 0.238" on the hot tip drawing. I have been drilling the hole to a diameter of 0.242" when I manufacture them because the average diameter of the insulating Teflon is 0.250" and it is still hard to insert the Teflon. Currently there is consideration of increasing the outside diameter of the end with external threads so that the inside diameter can also be increased to better fit the Teflon, and not further increase the difficulty of manufacturing by reducing the tolerance between inside and outside diameters. However, this would also require that the holes in the extruder plate also be re-bored and tapped to a larger diameter to accommodate the larger diameter of the new hot tip design. I am going to first try to bore the inside diameter for the Teflon insert a larger spec of 0.246" using drill bit "D" instead of "C". This way we can avoid re-boring all the extruder plates, and re-use all existing hot tips.
Plastic Recyling: Building a DIY Mini Shredder
Another project I am involved in with Sam Carroll is building a DIY Mini Shredder based on the design of thymark's youtube channel instructions found here.
Re-Design of RepRap Extruder Location
Basically the purpose of this new design is to separate the extruder motor from the carriage that runs overtop the printer bed. To do this, a long piece of Teflon will be ran to the carriage system and bound to one side of the current extruder plate, while the hot tip is attached to the other side. The long piece of Teflon is pictured below, and the prototype design of how the hot tip, extruder plate and Teflon will be attached is currently being worked on. The first Bowden Type extruder design for SCRUG was recently completed. The current design I was able to come up with can be found here
Bowden Extruder Prototype Design
The Bowden extruder design allows the extruder body/motor to be separated from the extruder plate so that just the plate and hot tip are attached to the carriage. A long piece of Teflon then connects the hot tip and extruder.
The current prototype design was created with the intention of being able to use existing hot tips and extruder plates. The hot tip steel body has to be slightly modified by extending the external threads. This allows the steel body to protrude about 0.300" through the other side where the drilled and tapped 1/8" brass plug is attached. Then, an 1/8" brass coupling is used to connect the brass plug and Teflon quick disconnect fitting.
Brass Coupling Hex Style P/N: 50785K91
Brass Plug Solid P/N: 50785K334
Delta Bot Plates
These are the plates made for the new classroom delta bot, as well as 2 for Nate's delta bot. The classroom version was made to accept our current hot tip design, and Nate's were made to accept an E3D J-Head. Special thanks to Sam Descutner for running the mini mill to make the plates for me this semester. He should be recruited for this class.
