Tonight’s meeting was a great success, thanks in large part to Tom’s Balloon Animals presentation/workshop. Â Members and visitors were shown, and then guided through making a variety of plants, animals, and inanimate objects.
Additionally, we had a number of visitors, and worked on projects including a Peltier-cooler proof of concept and a grinder stand. We also dusted off an old Teletype, in preparation for it’s impending Twitterification.
If I hadn’t seen this myself, I don’t know that I’d believe it. Last night, we set out to test this Popsci article, and it seems to hold up.
We had 2 locks donated, a generic U-Lock, and a pretty beefy looking keyed padlock. The U-Lock’s steel turned out to be a bit too soft, and just bent a bunch, but the shackle on the padlock failed relatively quickly.
All said, we used 2 cans of air, but quite a bit of that was spent on the first lock. Both the body of the lock and the shackle sustained quite a bit of damage, though the damage to the body was mostly cosmetic and probably not “breaching”.
If I were to try it again, 2 things: 1. Strike the shackle directly, with a chisel or something, instead of the hammer face. 2. More lighting. Â The high-speed video was too dark to really show anything interesting. Â I keep forgetting how much light that thing takes..
A while back, we decided that we needed a 24v power source for various “testing” applications. This source needed to be durable enough for daily use by a wide variety of people without becoming damaged. It also needed to protect the device being powered, and be easy to maintain.
Given that tall list, Ben suggested a HobbyKing LiPo pack, 6S, 5Ah. With that start, we decided that it should have volt and amp meters for monitoring, as well as a circuit breaker to provideÂ positiveÂ power disconnect, and protect the battery (easily capable of 150A into a dead short).Meters were ordered from Ebay and the breaker was something out of an old UPS.
The blue enclosure is a waterproof storage box from Walmart, modified to pass through various connectors. Â It’s not waterproof at this point, but we’re more after the durability of the polycarbonate than the waterproof aspect anyhow.
Internally, there’s quite a bit going on. Â The battery is packed into a foamed-off area, while the other side contains the electronics, including the circuit breaker,ammeter shunt and all the connectors.
Charging is accomplished via a modified ATX connector (which re-presents the balance plug and main power leads), with a fuse to protect against abuse. The idea is that it’s virtually impossible to charge the battery improperly, or to break a relatively fragile balance connector.
Overall, it was a pretty straight-forward build, and cost around $90, including the battery and all the connectors.
Just a reminder, the Omaha Maker Group’s regular meeting on Tuesday, September 4th is an Omaha Creative Week Spark Event. We have several presentations on the docket, including a summary of the Omaha Maker Group (and Making as a whole), as well as a hands-on presentation on manipulating your car’s onboard computer for diagnostics and customization.
Hope to see everyone there! Â If you have questions, don’t hesitate to email firstname.lastname@example.org.
As part of the recent OMGWTFBBQ festivities9, a contest was held, pitting the forces of gravity against the weight of cold hard cash (pennies, to be specific). Â The goal of the contest was to use soda straws to support as much currency as possible in as high of a position as possible, thus racking up the most “inch-cents” of score.
As it turns out, we ended up going to “foot-dollars” and using weights that weren’t exactly copper, given the engineering of some of the entries. Check out the results below.
|Stephanie & Cait||8.25||2898||23908.5||19.92|
|John & Don||11.25||271.5||3054.38||2.55|
|Claire & Dad||7.5||271.5||2036.25||1.70|
|Jess & Company||14.25||45||641.25||0.53|
|Patrick & Travis||19.375||14||271.25||0.23|
|Ben & Dave||11.5||0||0||0|
This past weekend,Â Dave and Eric and I met up with quite a few Omaha Maker Group members at the KC Maker Faire, and had a blast. Â We were initially going to have a booth to show off the awesome projects from around the Makery, but had far more people who wanted to go See the Faire instead of Work At the Faire. Â Somehow, this change was miscommunicated to the Powers that Be, and we ended up with a booth and sign anyhow (notably unmanned).
WeÂ definitelyÂ got to see some neat stuff, including one of those optical-resin based 3D printers. ArcAttack was pretty awesome as well, if amazingly loud.
Beyond that,Â Â it was an excellent a venue to share ideas… Looking through my pictures, I think Eric and I had identified at least 3 or 4 projects we want to try, and dozens of smaller ideas. Â I saw a few 3d printer innovations, a “bubble printer” (by ArchReactor), Â a portable whiteboard cart (For the Makery, at Hammerspace); We also a “waterflow table” (aka a Sluice Box) at Science City, where it pumps water down a trough, and you insert dividers to change the flow paths. Â It seems pretty trivial, but would be one of those “fun to mess with” sorts of things.
I was a bit surprised that there wasn’t more merchandise (specifically Arduino kits and whatnot), although I’m not sure that this was a bad thing, in retrospect.
Last Sunday (April 1st) was the first Omaha Maker Group Egg Drop. Â The competition was much in the same style as the Nerf Gun Mod Contest run last fall; This competition had a lower entry barrier, and thus far greater turnout, with 10 total entries (Eric entered twice). Â All the eggs survived the drop, but Stephanie was the big winner, with a score that bested the next entrant by a factor of 4. Click through for full results, and a little high-speed video, thanks to Ben. Continue reading
On Tuesday night, we were disassembling some old printers, and salvaged some large ROM chips. Patrick got the idea to use the mill to remove the top layer of the case, and expose the IC inside. Â Here are some photos we took of the chip’s insides with a microscope. Magnifications range between 4x and 40x, thought the 40x were pretty difficult to illuminate properly, because the lens obscures most of the light. As for the cameras, we Â used a little point and shoot and a cell phone camera, both just held up to the microscope’s eyepiece.