RepRap Acrylic Extrusion Using Hotbed

[Nophead] started the year off by successfully extruding acrylic using a RepRap machine. The problem when working with this material is that when the hot ooze hits the cold air the printed material tends to warp, badly. [Nophead] raised the ambient air temperature around the part being extruded by replacing the bed of the RepRap machine with a heated aluminum plate.

We took at look at his build details for the hotbed. The plate itself is aluminum that he had milled by a machinist friend of his. It looks like the heat is produced by a network of power resistors bolted and soldered to the bottom of the plate. The original idea was to produce a controllable SMT soldering platform. Unfortunately this heating method doesn’t have the power needed to raise the temp quickly but that failure turned out to be a RepRap success.

Punching Out Parts

If you’re more of a code monkey than artist, it may be tough to transform your ideas into the 3D models necessary for fabbing. The folks working on openSCAD apparently feel our pain.

openSCAD uses a language somewhat reminiscent of C for creating models. A preview of the model is rendered alongside your code. Fully cross-platform, it runs on Linux, OS X, and Windows. Much like SketchUp, openSCAD can also extrude 2D outlines into models. This feature comes in very useful if one already has a set of technical drawings for a part. With no price tag, it’s pretty affordable during this costly season.

Sarrus Linkage 3d Printer

[fdavies] has been working on his own 3d printer. He is using printed parts, but unlike the RepRap he’s purposed Sarrus linkages in his design. If it works, this should remove the need for precision rods in building these types of CNC based machines. He’s also recovered DC motors and optical encoders from some inkjek printers. Given that many retailers require you to take junky inkjets home when you purchase a computer we’re betting you’ll find friends happy to part with their unused hardware. We’re impressed with the motion of the prototype seen after the break. Let’s hope this leads to the next generation of affordable 3d printers.

Continue reading “Sarrus Linkage 3d Printer”

Hackaday Links: Sunday, November 29

Sometimes we wonder if we’re making good choices with PCB layout when using EagleCAD. Watch how the pros do it with a video of an hour-long Adafruit PCB layout session compressed into seven minutes.

[Elijah] documented his RepStrap build. This is a chicken-or-egg project in that RepStrap machines are built without the assistance of an already existing RepRap.

Here’s an ASUS concept from CeBIT this year for a laptop that has two touch screens and no physical keyboard. Isn’t this just the DS project we saw this week but in a nice case?

[James] conjured up a physical realization of the Spinning Wheel of Death for an art exhibit. We can’t stop smiling when looking at this artful hack.

I’m sure nobody will raise an eyebrow when you pop out that roll of duct-tape and affix your phone to the airplane window. That’s what [floe] did to make this airline flight time-lapse video with an Android phone. Aren’t you supposed to turn off all electronics for takeoff?

Linear Optical Encoder

dsc03989

Optical encoders are nothing new; they can be found in everything from mice to printers. They’re great for allowing DC motors to know their exact position and even current direction. If this is sounding like old hat, it’s because we’ve shown you rotational versions before.

[Chris] uses the same concept, but produced a linear optical encoder instead of rotational. His setup is much like whats used in non stepper-motor CNC and RepRap mills, allowing ordinary DC motors to know their position within a plane. It’s a quick tutorial, but we liked the detail and it reminded us we need to finish that DC motor based mill thats still a pile of parts in the closet. Check out a video of [Chris’] in action after the break. Continue reading “Linear Optical Encoder”

RepRap – In Space! (sorta)

[vimeo http://vimeo.com/7141942%5D

We aren’t exactly sure how or even why you would need to RepRap in space, but we guess their team needed something to do while designing and printing their next version. They figure that if they can print completely upside down in -1G and then upside up in 1G, that 0G hopefully wont be a problem; hopefully being the keyword.

Even if it isn’t true space printing, the concept opens several new doors. Instead of having risky rocket or shuttle launches when the secondary air oscillator on the IIS is struck by an asteroid, print a new one. Or perhaps, the ocean floor research facilities’ external hull is punctured by an asteroid, print a new one. Or the HaD office chair breaks because [Mike] was hit by an asteroid, print a new one.

Lets not get ahead of ourselves here. But alongside circuit board printing, perhaps in-home fabrication is the way of the future. What would you like to print? Before you answer, yes, we will release the [Mike©] plans.

[Thanks Julius]

RepRap Milling Machine

three axis cnc robot with vacuum attachment

[Chris] liked Cartesian RepRap idea so much that he decided to design his master’s diploma project around it. Though it uses most of the same parts as the RepRap (even the PCBs), [Chris] has adapted it so it does milling rather than 3D printing.  Most of the parts (such as the stepper motors) were harvested from old inkjet printers and typewriters. The thee-axis CNC machine can already etch and carve styrofoam at an impressively high resolution. To deal with all of the debris that comes with milling, a vacuum attachment (shown attached) was created. [Chris] is considering adapting it so it can work with wood and aluminum as well. Best of all, it uses standard G-code files, just like the RepRap. A publication by [Chris] on the project is also available through his website. No plans to release a kit have been announced yet, but we’ll wait and see. If any commenter knows of an open source CNC milling machine available as a kit, feel free to post a link to it below.