[Chris] has been having some real problems getting PLA to stick to the build platform of his Printrbot. This is of course not limited to this brand of printers, and affects all extruder-based hardware using the PLA as a source material. He came up with a couple of ways to fix the problem.
The first is something we’re quite familiar with. The image above shows [Chris] applying a thin layer of hairspray to the platform. This is a technique the we use with our own 3D printer. The sheets of paper are used as a mask to help keep the sticky stuff off of the threaded rod. For more info on the hairspray trick [Chris] recommends that you read this article.
The second technique uses a slurry made from saturating a bottle of acetone with ABS leftovers. In the clip after the break he shows off a glass jar of the solvent with scraps from past print jobs hanging out inside. After a couple of days like that it’s ready to use. He takes a paper towel, wets it with the solution, and wipes on a very small amount. He does mention that this will eventually eat through the Kapton tape so apply it rarely and sparingly.
If you’ve ever used an extruding 3D printer, you know that the resulting prints aren’t exactly smooth. At the Southackton hackerspace [James] and [Bracken] worked out a method of smoothing the parts out using vapor. The method involves heating acetone until it forms a vapor, then exposing ABS parts to the vapor. The method only works with ABS, but creates some good looking results.
Acetone is rather flammable, so the guys started out with some safety testing. This involved getting a good air to fuel mixture of acetone, and testing what the worst case scenario would be if it were to ignite. The tests showed that the amount of acetone they used would be rather safe, even if it caught fire, which was a concern several people mentioned last time we saw the method.
After the break, [James] and [Bracken] give a detailed explanation of the process.
If you’re thinking of trying the acetone-vapor polishing process to smooth your 3D printed objects you simply must check out [Christopher’s] experiments with the process. He found out about the process from our feature a few days ago and decided to perform a series of experiments on different printed models.
The results were mixed. He performed the process in much the same way as the original offering. The skull seen above does a nice job of demonstrating what can be achieved with the process. There is a smooth glossy finish and [Christopher] thinks there is no loss of detail. But one of the three models he tested wasn’t really affected by the vapor. He thinks it became a bit shinier, but not nearly as much as the skull even after sending it through the process twice. We’d love to hear some discussion as to why.
There is about eight minutes of video to go along with the project post. You’ll find it after the jump.
While researching copper plating graphite for a project, [Dave] stumbled upon a blog post illustrating a brilliant approach to metal plating 3D printed parts.
Our pioneers in this new technique are [Aaron], who runs a jewelry business, and [Bryan], a professor of Digital Media. By mixing graphite powder into an acetone solution, it is possible to make a kind of graphite paint that sticks extremely well to ABS plastic.
Using the graphite painted part as the cathode, and a chunk of copper as the anode, it becomes possible to electroplate the part with a variety of electro-forming solutions. In the first test (seen above), [Bryan] uses a Midas Bright Electro-forming Copper Solution (copper sulfate solution).
Tired of the persistent hum his fluorescent desk lamp made, [Andres Lorvi] decided he had to fix it. And by fix, we mean get rid of altogether. He liked the lamp though so he decided to convert it to LED — that way he’d save some money on electricity too!
Besides wanting to get rid of the hum, [Andres] had also been reading up on the effect of light temperature at night — bluish light is typically bad for your eyes when you’re trying to go to sleep. So he also took this opportunity to change the color temperature of the light in his room. Unfortunately it wasn’t as simple as just replacing the fluorescent with the LEDs — no, that would be far too easy…
About a decade ago I started a strange little journey in my free time that cut a path across electronics manufacturing from over the last century. One morning I decided to find out how the little glowing glass bottles we sometimes call electron tubes worked. Not knowing any better I simply picked up an old copy of the Thomas Register. For those of you generally under 40 that was our version of Google, and resembled a set of 10 yellow pages.
I started calling companies listed under “Electron Tube Manufacturers” until I got a voice on the other end. Most of the numbers would ring to the familiar “this number is no longer in service” message, but in one lucky case I found I was talking to a Mrs. Roni Elsbury, nee Ulmer of M.U. Inc. Her company is one of the only remaining firms still engaged in the production of traditional style vacuum tubes in the U.S. Ever since then I have enjoyed occasional journeys down to her facility to assist her in maintenance of the equipment, work on tooling, and help to solve little engineering challenges that keep this very artisanal process alive. It did not take too many of these trips to realize that this could be distilled down to some very basic tools and processes that could be reproduced in your average garage and that positive, all be it rudimentary results could be had with information widely available on the Internet.
When you need precise heating — like for the acetone polishing shown above — the control hardware is everything. Buying a commercial, programmable, controller unit can cost a pretty penny. Instead of purchasing one, try creating one from scratch like [BrittLiv] did.
The system she developed was dealing directly with temperatures up to 338°F. The heating element is driven from mains, using an SSR for control but there is also a mechanical switch in there if you need to manually kill the element for some reason. An ATmega328 monitors the heating process via an MAX6675 thermocouple interface board. This control circuitry is powered from a transformer and bridge rectifier inside the case (but populated on a different circuit board).
She didn’t stop after getting the circuit working. The project includes a nice case and user interface that will have visitors to your lab oohing and aahing.