Just to be clear, the primary goal of the Papas Inventeurs (Inventor Dads) was to have the kids make something, have fun, and learn. In that light, they enjoyed a huge success. Four children designed, made, and sold laser-cut napkin rings from a booth at the Ottawa Maker Faire as a fun learning process (English translation, original link in French.) [pepelepoisson] documented the entire thing from beginning to end with plenty of photos. Things started at proof of concept, then design brainstorming, prototyping, manufacture, booth design, and finally sales. While adults were involved, every step was done by the kids themselves.
It all began when the kids were taken to a local fab lab at the École Polytechnique and made some laser-cut napkin holders from plywood for personal use. Later, they decided to design, manufacture, and sell them at the Ottawa Maker Faire. Money for the plywood came from piggy banks, 23 different designs made the cut, and a total of 103 rings were made. A display board and signs made from reclaimed materials rounded out the whole set.
In the end, about 20% of people who visited and showed interest made a purchase, and 60 of the 103 pieces were sold for a profit of $126. Of course, the whole process also involved about 100 hours of combined work between the kids and parents and use of a laser cutter, so it’s not exactly a recipe for easy wealth. But it was an incredibly enriching experience, at least figuratively, for everyone involved.
Possibly the biggest takeaway was the way manufacturing involved much more than just pressing “GO” on a laser cutter. Some pieces needed sanding after laser cutting, and each piece got two coats of varnish. If you missed it, [Bob Baddeley] showed how labor, and not materials, ends up being the most expensive part of a product.
It has never been easier to put a microcontroller and other electronics into a simple project, and that has tremendous learning potential. But when it comes to mechanical build elements like enclosures, frames, and connectors, things haven’t quite kept the same pace. It’s easier to source economical servos, motors, and microcontroller boards than it is to arrange for other robot parts that allow for cheap and accessible customization and experimentation.
That’s where [Andy Forest] comes in with the Laser Cut Cardboard Robot Construction Kit, which started at STEAMLabs, a non-profit community makerspace in Toronto. The design makes modular frames, enclosures, and basic hardware out of laser-cut corrugated cardboard. It’s an economical and effective method of creating the mechanical elements needed for creating robots and animatronics while still allowing easy customizing. The sheets have punch-out sections for plastic straws, chopstick axles, SG90 servo motors, and of course, anything that’s missing can be easily added with hot glue or cut out with a knife. In addition to the designs being open sourced, there is also an activity guide for educators that gives visual examples of different ways to use everything.
Cardboard makes a great prototyping material, but what makes the whole project sing is the way the designs allow for easy modification and play while being easy to source and produce.
STL files are everywhere. When there’s something to 3D print, it’s probably going to be an STL. Which, as long as the model is good just as it is, is no trouble at all. But sooner or later there will be a model that isn’t quite right in some way and suddenly project progress hits a snag.
When models interface with other physical things, those other components may not always be exactly as the designer expected. Being mindful about such potential inconsistencies during the design phase can help prevent problems, but it’s not always avoidable. The reason it’s a problem is because an STL file represents a solid model as a finished unit; it is not really intended to be rolled back into CAD programs for additional design changes.
STL files can be edited, but just like re-modeling a component from scratch, it can be a tricky process for those who don’t live and breathe this stuff. I’ll describe a few common issues related to STLs that can hold up getting that new project together, along with ways to deal with them. Thanks to 3D printing becoming much more commonplace, basic tools are within reach of even the least CAD-aware among us.
Continue reading “3D Printering: When an STL File is Not Quite Right”
Back in the 70s when I started getting interested in electronics, tons of magazines catered to the hobbyist market. Popular Electronics was my favorite, and I think I remember the advertisements more than anything, probably because they outnumbered articles by a large margin. Looking back, it seemed like a lot of ad space was sold to companies hawking the tools and materials needed for wire wrapping, which was very popular for prototyping in the days before solderless breadboards were readily available. I remember beauty shots of neat rows of small, gold posts, with stripped wires wrapped evenly around them.
To the budding hobbyist, wire wrapping looked like the skill to have. With a huge selection of posts, terminals, and sockets for ICs and discrete components, as well as a wide range of manual and powered wrapping tools, it seemed like you could build anything with wire wrapping. But fast forward just a decade or so, and wire wrapping seemed to drop out of favor. And today — well, does anyone even wire wrap anymore?
Continue reading “Ask Hackaday: Whatever Happened to Wire Wrapping?”
[Dickel]’s robot MDi #4 has been in progress for several years, but what we wanted to draw your attention to is the way the parts have been fabricated and what kind of remarkable results are possible with careful design, measurement, cutting, and finishing. Much of MDi #4 was made by hand-cutting and drilling sheets of high impact polystyrene (HIPS) with a utility knife and layering them as needed. Epoxy and aluminum provide gap filling and reinforcement of key sections, and fiberglass took care of one of the larger sections.
The process [Dickel] follows is to prototype using cardboard first. Parts are then designed carefully in CAD, and printed out at a 1:1 scale and glued to sheets of polystyrene. Each sheet is cut and drilled by hand as necessary. Layers are stacked and epoxied, embedding any hardware needed in the process. Two examples of embedding hardware include sealing captive nuts into parts with epoxy, or using aluminum to add reinforcement. After some careful sanding, the pieces look amazing.
Scroll down a bit on that project page and you’ll see plenty of great photos of the process [Dickel] used. A video highlighting the head and a video showing the careful work that goes into making each part are embedded below.
Continue reading “These Gorgeous Robot Parts are Hand-Made”
[Tommy] is a one-man-shop making electronic musical things, but that’s not what this post is about. This post is about the outstanding prototyping post-mortem he wrote up about his attempt to turn his Four-Step Octaved Sequencer into a viable product. [Tommy] had originally made a hand-soldered one-off whose performance belied its simple innards, and decided to try to turn it into a product. Short version: he says that someday there will be some kind of sequencer product like it available from him, “[B]ut it won’t be this one. This one will go on my shelf as a reminder of how far I’ve come.”
The unit works, looks great, has a simple parts list, and the bill of materials is low in cost. So what’s the problem? What happened is that through prototyping, [Tommy] learned that his design will need many changes before it can be used to create a product, and he wrote up everything he learned during the process. Embedded below is a demo of the prototype that shows off how it works and what it can do, and it helps give context to the lessons [Tommy] shares.
Continue reading “Learn What Did and Didn’t Work In this Prototyping Post-Mortem”
[Dickel] always liked tracked vehicles. Taking inspiration from the ‘Peacemaker’ tracked vehicle in Mad Max: Fury Road, he replicated it as the Mad Mech. The vehicle is remote-controlled and the tank treads are partly from a VEX robotics tank tread kit. Control is via a DIY wireless controller using an Arduino and NRF24L01 modules. The vehicle itself uses an Arduino UNO with an L298N motor driver. Power is from three Li-Po cells.
The real artistic work is in the body. [Dickel] used a papercraft tool called Pepakura (non-free software, but this Blender plugin is an alternative free approach) for the design to make the body out of thin cardboard. The cardboard design was then modified to make it match the body of the Peacemaker as much as possible. It was coated in fiberglass for strength, then the rest of the work was done with body filler and sanding for a smooth finish. After a few more details and a good paint job, it was ready to roll.
There’s a lot of great effort that went into this build, and [Dickel] shows his work and process on his project page and in the videos embedded below. The first video shows the finished Mad Mech being taken for some test drives. The second is a montage showing key parts of the build process.
Continue reading “Glorious Body of Tracked ‘Mad Mech’ Started as Cardboard”