2018-06-29 I've had pretty good luck with PLA plastic holding up to metalworking fluid and I am currently running a collar on my mill that mounts my coolant spray nozzles and acts as a manifold for the coolant. It is available on thingiverse here: https://www.thingiverse.com/thing:2983210
2017-12-04 I have developed and published a belt compliance test fixture on the reprap wiki. Why would anyone bother? Belt stretching = part inaccuracy. I did it because I could not find any numerical data on how much I should expect the belts typically used in a 3D printer to stretch when a certain amount of force was put on them. I also want other people to contribute their data to pool of knowledge on the web so that I can have factual information on the compliance of belts of various constructions and origins. By publishing the design for the test fixture I hope to create a consistent basis for the measurements.
2017-11-22 I am currently in the process of designing a better 3D printer for myself. What does better mean? With so many 3D printer designs out there, why can't I just pick something that is already engineered? Well -- I love experimenting with ideas and making things "better." Better is really subjective word. Today, I think better would be:
Mechanically precise, but without paying through the nose for those rectangular cross section linear bearings. I have done some experiments with using bearing trucks and sustainable technology. I want to use the frame of the machine as part of the guiding system, but not have it be imprecise or expensive. I'm a little down on the use of v-wheels because they aren't usually axially pre-loaded in a way that inspires my confidence. So I am toying with other ideas here. The standard 8mm rods, and even the 10mm rods bow under their own weight and the weight of the Y carriage.
Has a heated build volume. ABS printing works for me but can be frustrating. I think a heated build chamber would help me a lot.
Safe: I want to eliminate single point failures that can result in your house burning down. Like:
MOSFET fails on.
Relay sticks.
Arduino fails to boot.
Arduino output fails.
Thermistor pulls part way out
Wire breaks
Vref on arduino gets goofy.
On par with the cost of existing entry level kits.
Reliable
Robust mechanically
Maintainable wear parts
Doesn't take fiddling with every time one goes to make a print.
2017-10-23 Today I printed a toiled paper holder rod. I pumped up the temperature on white PLA from Microcenter to 220C for printing. It yielded little fuzzies like printing in PETG, but the layer adhesion was the best I have ever seen. It made for a surprisingly robust part considering the thin walls. I thickened them up, and created a rubber band based spring pin. It is published on thingiverse
https://www.thingiverse.com/thing:2603759
https://thingiverse-production-new.s3.amazonaws.com/renders/fe/b6/b2/23/88/9c18e8dbf9e7a0bdd1a456c6a2cfaa09_preview_featured.jpg