A Technique To Avoid Warping On Large 3D Prints

November 15, 2011 by Mike Szczys 42 Comments

[Jamie Mantzel] figured out his own way of 3D printing large objects without fear of warping. First a bit of background information. When using a 3D extrusion printer like the RepRap or Makerbot, prints that span a large area tend to warp. That’s because these printers lay down one thin layer of plastic at a time. If the first layer cools too much, it will shrink a bit before the next layer is laid down. As that second layer cools it pulls the part toward the center, eventually bowing the part which causes it to hit the extruder head.

After having several prints encounter this issue [Jamie] decided to alter his design so that it wouldn’t cause these stresses. The first thing that he did was to add alternating voids to a layer between the raft and the actual part. You can see these as notches on the bottom the piece pictured above. This takes care of the initial stresses from the first layer. Next, he adds holes wherever he can in the main body of the part. This is especially important on the edges of the piece where the warping forces will be the greatest.

He also moved the starting position of the bed closer to the extruder head. His hope is that this will help the raft bond better, and resist pulling away from the bed during printing.

See his video explanation of his adventure after the break.

Continue reading “A Technique To Avoid Warping On Large 3D Prints” →

Build Your Own Stereolithographic 3D Printer

November 14, 2011 by Mike Szczys 26 Comments

[Andy’s] 3D printer build uses lasers to create objects from goo. The Stereolithographic process uses resin that is cured by UV light to create the finished product. A single laser mounted to a CNC gantry is able to precisely target a point on the surface of the resin to begin the printing process. As the layers are built up, the stage, which is mounted on the Z axis, slowly sinks into the resin vat. So basically you’re printing from the bottom up but the laser never moves up or down. There’s a time-compressed video of an object being printed embedded after the break. It illustrates the process better than we can describe it.

We think [Andy] really went all out with his write-up of the build process. The quality he achieves in his prints is quite excellent, but you must consider the cost versus an extrusion-based 3D printer. One liter of the UV resin he prints from can cost over $200.

If this sounds familiar it’s because we got a sneak peek at it back when we looked in on his Delta robot work.

Continue reading “Build Your Own Stereolithographic 3D Printer” →

3D Printed Electromechanical Computer

October 27, 2011 by Brian Benchoff 23 Comments

A few nights ago, [Chris Fenton] was hanging out at NYC Resistor putting in some time on his electromechanical computer project. You might remember [Chris] from his tiny Cray that he’s putting an OS on. It seems [Chris] is going back in time about 150 years and has set his sights on a 3D printed version of [Babbage]’s Analytical Engine.

The Analytical Engine ~~was~~ is a remarkable feat of engineering and machining. It was the first programmable computer. Shame, then, that it was never built in the 1800s. [Chris] isn’t building a glorified calculator like [Babbage]’s polynomial-computing Difference Engine – he’s going all out and building something with conditional looping.

[Chris] calls his device an electromechanical computer, so we’re assuming it won’t be crank driven like the version in the British Science Museum. Right now, he’s constructed the decade-counting gears that are vitally important for the ALU of his design. All the parts were printed on a Thingomatic, so we’re betting [Chris] is going to be relying heavily on the MakerBot automated build platform for the thousands of parts he’ll have to fabricate.

Check out the video from NYC Resistor after the break.
Continue reading “3D Printed Electromechanical Computer” →

14-part RepRap Saga Draws To A Close

October 21, 2011 by Mike Szczys 17 Comments

Behold, another RepRap springs into existence! Well, springs might not be the best choice of words, it took a while and there were many bumps in the road. But [NBitWonder’s] self-built RepRap is now finished and you can read his 14-part build log to see all that went into the process.

We checked in on the project at one of the early stages. At that point he was just beginning to assemble the hardware and we mused that the calibration stage is where we thought things would get exciting. The project didn’t disappoint, as he had many follies getting the extruder heads to work. At first some issues popped up when figuring out what diameter filament would work for the print head he was using. Once that was worked out, a less-than-precise PID controller led to the clogging and eventual destruction of the extruder tip. He goes on to assemble and test a heated build platform only to discover that the resistors shipped with the hardware are shockingly underrated for the task. We could go on and on, but that would ruin the fun for you. Bookmark this one for the weekend and enjoy!

Multicolor 3D Prints The Hard Way

October 19, 2011 by Brian Benchoff 6 Comments

After drooling over the Makerbot dual-head extruder, [Brett] decided to get off his duff and make a proper multi-color print.

[Brett] has been making a few bottle openers for friends and has been successfully experimenting with switching filaments in the middle of a print. For his “Saturday Killer” bottle opener, he decided to push multicolored prints to the limit. For the “Saturday Killer,” [Brett] decided to print an abridged version of the classic Simpsons quote, “Beer, the cause of, and solution to, all of life’s problems” on the side of a bottle opener in 4 different colors.

The files necessary to print the Saturday Killer were generated in OpenSCAD. The general principle behind the design is to generate separate .STL files for the bottle opener and the sides, split those files into 2-layer chunks, and print those files while constantly adjusting the z-height. It’s not called the Saturday Killer for nothing, so [Brett] had to change the color of his filament 25 times.

A much simpler version of a complex multi-color print is [Brett]’s Shepard Fairey inspired self-portrait. Still, we’re thinking a dual head extruder is somewhere in [Brett]’s future. At least he’s got the technique down.

Ultimaker Quality FAQ Is Like Porn For 3D Printers

October 13, 2011 by Mike Szczys 72 Comments

Do you think it’s not really possible to get amazing resolution from extruder-based 3D printers? You’re wrong, and this post about the attainable quality of prints on the Ultimaker proves it. The Yoda bust seen above was printed with a layer thickness of 0.02mm. This is a hack in itself because this process actually used two different layer thicknesses. The interior of the print, which you can’t see, but serves as a support mechanism for the object was printed at 0.04mm, with just the visible perimeter printed in the smaller thickness. That trickery is just fine with us if this is the result.

[Dave Durrant] discusses the press the Ultimaker has received, which mostly focused on the relatively fast printing process this hardware uses. But he didn’t think the story of the quality you can get with the device was being told. So he put out a call on the mailing list to send in pictures of high-quality 3D prints and he wasn’t disappointed by the response. You’ll see images of busts, bodies, gears, animals, and art pieces. There’s information about how they were printed, but even those not interested in the particulars will appreciate the macro photography that gives you an up-close look at how far we’ve come with these table-top rapid prototyping machines.

[Thanks Taylor]

Cheap Ikea Camera Boom Ensures Shake-free Video

October 12, 2011 by Mike Nathan 19 Comments

ikea_webcam_jig

[Chris] recently got himself a nice web cam for documenting his Makerbot builds, and much like [Dino], he was looking for a way to get a bird’s-eye view of the action while keeping the camera nice and steady. While [Dino] ventured off to the hardware store, [Chris] tried a few different options that included tape, before heading off to Ikea to see what he could find.

$9 and a few Swedish meatballs later, he was on his way home with a “TERTIAL Work Lamp” that can be mounted on virtually any desk-like surface. He had to remove most of the web cam’s useless mounting hardware, doing the same with the lamp’s light fixture. He put together a small bracket in Google Sketchup, which he then printed out using his Makerbot.

It fit perfectly, and now he can get steady video of his Makerbot prints every single time.