This 3D Printed Syringe Static Mixer Does It All

July 8, 2018 by Steven Dufresne 20 Comments

One trick for getting the bubbles out of freshly mixed 2-part epoxy, aka degassing, is to go over it gently with the flame from a propane torch. But both the mixing and degassing take time. [Gianteye] came up with a 3D printed dual-syringe static mixing system which speeds up the process. He used it with silicone to get the difficult steps out of the way quickly for his hands-on soft robotics class, allowing the students to focus more on the matter at hand. But we figure most readers might use it for epoxy.

If you’ve bought those 2-part epoxy syringes available in stores before then you’ll know that they usually come with two syringes, each filled with one of the two parts to be mixed. Depressing the syringes causes each part to come out of its own tube. It’s then your job to mix them together and degas the result.

[Gianteye’s] system consists of 3D printed parts and two syringes. Models for the 3D printing are available on his Thingiverse page and the syringes can be found online. Some of the 3D printed parts help you first fill and degas the syringes. You then attach a 3D printed mixing tube to the ends of the syringes. This tube serves two purposes. When the syringe’s plungers are depressed, both parts of the material are forced through the tube and extruded out. But on their way through, both parts pass through eight helices which form 180° turns and mix the parts together. Out comes the portioned, mixed and degassed material which can go straight into a mold or to wherever you need it.

The mixing tube was designed for one-time use but [Gianteye] discovered during an evaluation that it can be reused if you pull out any cured material and purge it. The evaluation involved silicone though. With hardened epoxy, you’ll probably have to use a new tube each time.

Check out the full details of his system in the video below, including both assembly and usage.

If you’re looking for a metallic look for something without wanting to cast metal than have a look at our own [Gerrit Coetzee’s] article about cold casting wherein he makes some very nice looking parts.

Continue reading “This 3D Printed Syringe Static Mixer Does It All” →

Hackaday Links: February 4th, 2018

February 4, 2018 by Brian Benchoff 14 Comments

Here’s something remarkably displeasant. Can you cook a steak with glue? [Dom] and [Chris] from ExplosiveDischarge have cooked a steak using a huge, huge amount of two-part epoxy. The chemistry behind this is just the exothermic reaction when two-part epoxy kicks off, and yes, the steak (a very thin cut) was sufficiently wrapped and protected from the hot sticky goo. What were the results? An overcooked steak, actually. This isn’t a sous vide setup where the temperature ramps up to 50°C and stays there — the temperature actually hit 80°C at its peak. There are a few ways to fix this, either by getting a thicker cut of steak, adding some bizarre water cooling setup to keep the temperature plateaued at a reasonable temperature.

This is your weekly reminder for the Repairs You Can Print contest.

We’ve got a twofer for awesome remote-controlled hovering stuff. The first is a 1:8 scale Harrier. This plane designed and built by [Joel Vlashof] will be a reasonably accurate model of a Harrier, capable of VTOL. It’s built around a huge 130mm EDF, powered by 2x6s lipos, and stabilized with a kk2.1 flight controller with VTOL software. This is as accurate a Harrier that you’re going to get in such a small format, and has the cool little spinny vanes that allow the beast to transition from vertical to horizontal flight.

Want some more cool hovering things? [Tom Stanton] is building a remote controlled Chinook. Yes, that helicopter with two main rotors. The usual way of doing this is with proper helicopter control systems like collectives and Jesus nuts. [Tom]’s building this version with standard quadcopter technology, mounting a motor to a servo, and doubling it up, and mounting it on a frame. In effect, this RC Chinook is the tail boom of a tricopter doubled up on a single frame. It does fly, and he’s even built a neat foamboard body for it.

SpaceX’s Falcon Heavy is going to do something next Tuesday, sometime in the afternoon, east coast time. Whatever happens, it’s going to be spectacular.

Hey, it’s time for a poll. I need to decide between ‘tide pod’ and ‘solo jazz’. For what I’m doing, the cost and effort are the same, I just need to know which is more ａｅｓｔｈｅｔｉｃ, cool, or whatever. Right now it’s 50:50. One must be crowned victorious!

Here’s the stupidest thing you’re going to see all year. That’s someone looping a quadcopter in front of a Frontier A320 (Probably. Seems too big for a 319 and too small for a 321) on approach. This guy is 3.6 miles East of runway 25L at McCarran Internation in Las Vegas, at an altitude far above the 400-foot limit. Judging from the video and the wingspan, this quad came within 200 feet of a plane carrying at least 150 people. It’s the stupidest thing you’ve ever seen, so don’t do it. It’ll be great to see the guy responsible for this in jail.