Harry Coover, inventor of Super Glue, has passed on March 26, 2011, at the age of 94.
His work helped save countless lives during wartime and continues to be used in modern surgery. Of course it is also a staple supply for many, many other industries and hobbyists.
Please join me in a minute of silence today in honor of this true hero of hackers, makers, and workers everywhere. Pouring one out for you, buddy.
After the overwhelming success of last month's Hacker Potluck, we invite you to join us at 23b Shop's next SoCal Hacker Potluck on March 19th.
POTLUCK: Bring something to eat, or whatever you want. Do think about it. We do get down with some good food and encourage you to do so as well -- for instance, delightful crepes were made on the spot last month at an Extemporaneous Crepe Workstation set up by one of our industrious attendees. We challenge you to be as amazing as this.
DO WHAT?: You are welcome to come have or make dinner, present a presentation, hang out and listen, gawk, do whatever it is you do, find and talk with someone doing way cooler stuff than you are doing, mingle, snipe bids, rant and rave, leaflet, throw business cards, bring minions, dance and sing, etc. Present a recent project to the group using multimedia resources. Bring video of your latest project, or the project itself. Network with some of the finest people in your area.
DON'T WHAT?: This isn't a work night for noisy machine tools, but we are a workshop so if you find the need to work on something for great win, we may accommodate you. If you know someone who is doing outlandish or amazing things and hasn't come here, we encourage you to kidnap them and make them entertain you here. Definitely make sure you don't default to being a merdone. TOOLS:We have a microwave, an amazing Signor Cappuccino coffee machine (*NEW * retro find, just brought in this month), a wicked old angry hot plate, an oxygen-acetylene torch or propane torch (...think of the Creme Brulee you could make!), a laptop, Mobile Club sound system with flashy lights, and projector, and whatever other items or tools you bring. Ask someone in charge if you have something in mind, and we may help to support your arbitrary and capricious requests.
Tiny bicycles are always available; ask someone who knows!
spectator -- this is the one place where people want to see your work and hear about your wild-eyed theory, no matter how kooky or mis-concocted.
WHERE and WHEN?: 418 E Commonwealth #1, Fullerton, CA (behind Stages Theatre and Pizza Hut. 1 block E of Lemon) Saturday, March 19th. 6pm until we are done.
We've found another budget printed circuit board supplier that is USA-based. They have a nice special running through July 31st, so we ordered 10 more access controls with some more minor improvements.
Please join us at the 23b Shop for big fun at our new SoCal Hacker Potluck and discussion. Bring a friend, or more, and try to let us know if you plan to show up.
TLDR: Potluck, Thurs, Feb 10th, 2011, 6pm or so. WHERE: 23b Shop, 418 E Commonwealth #1, Fullerton, CA 92832 WHERE!? (East of Lemon ~1 block, behind Pizza Hut)
FOOD:
- Bring something to eat and share. Plan on bringing enough food to feed several people and you can't go wrong. - Of course, making something to bring is best, but if you don't make food it's fine to pick it up. - Try to avoid the inelegant 'bag of chips' solution, unless you made bomb-ass salsa and need something to pick it up on. - If you're stuck on what to bring, use this E-Z cheat sheet (or bring whatever you like) Last name starts with A-M = entree, last name starts with N-Z = side dish or dessert or drinks - Gourmet food trucks meet right down the street, 1501 S. Lemon St. Fullerton, CA 92832. About 8 trucks are usually there Thursdays from 5-9.
NONFOOD:
- There will certainly be a heated discussion, tech demonstration, presentation, or something. Let us know if you have something you'd like to formally do for or to the group, or just show up with stuff. - There may be clown bike jousting, sharkfighting, or a steel cage machete battle after dinner. - Feel free to bring a project or something you did (or want to do) for show 'n' tell. - We have internets. We can also host slideshows and video and loud noises if you want. - What else would you like to see at a hackerspace pot luck? Bring it, and there it'll be!
Visit http://danozano.spreadshirt.com/ and pick up a 23b Shop shirt or two in any color. There are several designs and many colors available. The quality of the transfer is superior -- this is a tangentially cut logo made in layers and bonded to the shirt, not an inkjet or screenprint. The shirt will last a very long time with minimal wear.
So the new boards from 4pcb.com came in, and I got Open Access Control 2.0 completed. It works great, and the PCB actually seems to have no layout mistakes.
After spending about $500 on materials for the prototype and first 5 boards, it's exciting to finally see some results.
With any luck, this will help jump start more hackerspace access projects. The folks at Pumping Station One have also new wiki site for this sort of thing at www.hackcess.org.
For those that are not familiar with the project, this is an effort to make an affordable, open source door/building control available to everyone. It's based on the Arduino, and supports 2 door readers, 4 alarm/monitoring zone inputs, and 4 output relays. The main work has been making it robust, protected from surges and accidents, etc.
On another note, I got the urge to build an impulse sealer and pack up a kit to send to Black Lodge in Seattle. This is what $2.00 worth of Nichrome wire and a 6A lab power supply will do to a polyethylene bag. Woot!
More pictures: The revised Eagle CAD files, plus a full bill of materials and notes are up on the code site, and kits will be offered shortly. W00t!
After a lot of delays, we have now sent the PCB for Open Access Control 2.0 out for fab. We have added the following features:
-Reduced component count -On-board 5V switching power supply -Improved circuit protection with MOV and TVS diode -Opto-isolator layout can use NEC PS2501-1,2,or4 parts -Better mechanical layout -Full 5A continuous trace rating on all relays, 10A contact rating
This book was written in 1922 by an artillery school, and includes lots of info on hoisting and moving huge, heavy, delicate machinery, like cannons or machine tools or overturned/stuck vehicles. The book covers knots, leverage principles, and some of the basic tools that can be created to help the task.
Mostly you will be using manpower and simple leverage multipliers of all kinds, along with some good thinking about what you're doing. Thus the 'mind' part. Unfortunately they don't cover pure telekinesis in this volume; I'm still looking out for that book.
OBJECTIVE Build a robust, accurate rotary-to-linear motion transfer box within a weekend, without spending any money.
PLAN Some projects need an element that moves in a straight line, but this is not always as easy as getting rotary motion straight from a motor, pedals, or crank.
To accomplish this, I read online about mechanical linkages and selected a hypocycloid linkage. It has a very elegant and simple design, with a long linear travel for a small size. Rotary input (like a hand crank or drill) applied to the central shaft is converted to straight line motion across the diameter of the ring gear. The linear motion will be as long as the ring gear is wide.
BUILD I hand-cut two plywood gears on the bandsaw and built a frame to run them in. The ring or internal gear has 32 teeth, the round gear has 16 teeth. Using powers of two ensures both good support from the spirit world, and harmony with the geek nature.
My gears were cut from a paper pattern generated with the free online gear calculator at http://woodgears.ca/gear_cutting/template.html , which I printed out and glued right to the plywood.
According to the site's gear-making recommendations, this is sometimes a problem with laser printers -- though not with inkjets, since they have tighter registration requirements. I used a laser printer and measured the gear patterns in several places to ensure that the laser printer didn't stretch the image in any direction.
All parts were cut by hand on a bandsaw, trimmed by hand (very little) with a wood file, and finished and lubed with paste wax. 1/2" bolts and washers were used throughout.
FITTING Since the gears are hand cut, and since this is the first time I have made gears like this, there are small variances despite the saw being quite accurate and maneuverable. The dimensions aren't exactly perfect -- they are very close, however, and well within working tolerances.
I clamped all the various layers and spacers together, rotated the movement by hand and tested the path, tuning with a small hammer to tap the pieces into their best fit.
I aligned the teeth to find a combination that gave smooth travel without binding. I rubbed some wax into the teeth to ease their meshing up during the initial tests.
Then I chucked up a drill on the main shaft and gave a test run, repeating my tuning process and eventually screwing all the layers together when I was satisfied. I then ran it for a few minutes to work in the gears.
The time spent aligning the parts by hand provided a much better end result -- this was time well spent. I haven't finalized this as a working tool, just a prototype, so it's not painted. But it is sanded smooth and finished on all 6 sides, square, and generally nicely worked.
RESULTS The gearbox is quite stable, and it goes way faster than I would need. I estimate the main shaft got going at 200-240rpm, at the drill's fastest speed in high gear.
This was a successful project and consumed about 10 hours of time to plan and complete. (This includes the time spent taking the laser printer completely apart due to paper slippage problems, servicing the paper feed rollers, and reassembling it.)
WHAT I LEARNED This project was purposefully set up with very rough measurements throughout. I used it to improve my skills at eyeballing, guessing correctly without actually measuring anything, and improvising solutions precisely the first time.
I used a divider to copy one measurement --I needed to rebuild the center arm, but with a 1mm increase in length between the main shaft hole and the gear hole.
Everything else was strictly eyeballed, even measuring the center of the main axis hole was an eyeball measurement. This was probably not the best or easiest choice. But that was the point, to do something using basic hand techniques, and have the project come out working as planned despite the lack of laser cutters, CNC tools, or even exact measurements.
Don't be afraid to extend the boundaries of your ability and sharpen your techniques for making good guesses and improvising in your projects. It improves your work when you have more practice at deciding confidently off the cuff, and fixing as you go.
FUTURE REFINEMENTS * Add an adjustable counterweight to the main shaft to counter a minor wobble. - Apply a more attractive, durable finish like battleship grey spray paint. - Consider making parts in metal or acrylic. Heavier = more stable. - Add proper bearings for smoother and faster travel. These could be shop built or salvaged. - Add a better driver, like a crank or built-in electric motor.
This week we decided to build lasers. Not just any laser, but one that puts out 100KW pulses of Ultraviolet light. Okay, the pulses only last 1-2ns and it's hard to burn things with it, but it's still pretty cool. It's pretty easy to make from junk, and it uses Nitrogen right out of the atmosphere to lase. Check out the video:
This plier holder declutters several drawers of jewelry tools. I used a torch to forge and bend the scrap of rebar. I forged the center bar thinner to allow the smaller pliers with sprung handles to rest nicely alongside their larger cousins.
Handmade fids and awls (plus 2 bought ones)
I made up a few sets of hardwood tool blocks for my ever-growing collection of needle files, assorted bits, awls, and knot-tying fids. They get the tools sorted and visible, as well as helping protect sharp points and delicate files from getting the blood of the unfortunate on them, which rusts the metal.
Sandblasted dinosaurs were added for visual interest.
Salvaged pallet wood with nice nail stains and character.
The Open Access Control system is an electronic alarm and door access system currently in development by Arclight at the 23b Shop. It is open-source and open-hardware, meaning you can get in on the fun and build one yourself.
It is currently being tested for duty as a burglar alarm, door chime, and people tracking system. It logs door access data in syslog format, sends the data via ethernet, and has on-board memory as well for data, command, and user storage. Its real-time clock ensures accurate data logs.
A numeric keypad is attached for entering commands -- for example, make the door open , set to chime on open, stay unlocked for x minutes, lock and allow exit only, deny access to a user, add a user, learn an RFID fob, and so forth. More keypads can be added.
Inexpensive RFID readers allow the system to be deployed without compromising the building's doors, windows, or walls to mount a keypad at the entrance, though this could be done as well.
The strike is a standard electromagnetic building strike; there's no sense messing with such a great and overbuilt piece of hardware.
Homebrewed circuit boards allow fast prototyping
The system is built around an Arduino Duemilanova board with an Ethernet shield and custom hardware for the in/out devices. The boards were designed and built at the shop. Laser-printed PCB images and Fab-In-A-Box transfer resists were used to generate prototypes quickly and easily. An inexpensive ID card laminator applied the resists to the board material. A fast accurate etch was obtained by wiping ferric chloride onto the prepared board, which was a novel method that seemed to work more quickly than tank etching with the same chemical, with much less cleanup and chems used.
The power supply board
Users can build their own unit from scratch, or possibly obtain partial, full, or assembled kits by contacting the shop.
Hardware files and Arduino code are available here: http://blog.shop.23b.org/2010/10/open-access-control-v100-board.html
Users would be able to write code to support other functions of their own devising, like releasing poison gas, activating lasers or tranquilizer dart projectors. Of particular interest are the 'talking sentry', 'MOTD', and time-aware Mini-Bake Oven modules, all in various stages of development.
In a fit of motivation, I got the PCB etched for the Open Access Control. I used the "Fab in a Box" process from this company and got pretty good results. I didn't have quite enough heat on my toner transfer and ended up having to do some re-work with a Sharpie, but it works.
Check it out:
I got the purple base color by boiling in liquid RIT dye concentrate for about 15 minutes.
Hopefully, the Shop Party this weekend won't keep me from at least getting the components on there over the weekend.
So the I finally got around to finishing the circuit and PCB layout for the Open Access Control for Hacker Spaces.
Check it out:
The Arduino code and Eagle CAD files for the hardware are available for download at: Google Code Page
The current version supports: -2 Wiegand26 RFID door readers -4 Output relays (5A) -4 Alarm zones -Separate 12V (2) and 5v (1) power buses for sensors -Opto isolated inputs on everything -Ethernet board ready
Now to get the PCB etched, stuffed, debugged, tested...What could be simpler?
