Happy holidays, everybody!
23b got a Christmas present a little early. We now have updated manufacturing capability as the proud new owners of an [antique] Bridgeport mill. There's a motorcycle shop down the street from our unit that had some equipment no longer needed, so it's ours now. This is a 1955 Bridgeport M-head round ram mill, pretty much the last of its kind before switching to a dovetail ram. It's about 2/3 the size of a more modern Series 1 mill, which works out perfectly for our limited footprint at the shop. The electrical was hooked up today, thanks to Queeg, Dano and Arclight. Hopefully by the 1st of the year, we should be cutting chips. Combined with our lathe and welders, we are now your one-stop-shop for the upcoming zombie apocalypse in 2012.
Progress on the M.A.M.E. cabinet enclosure is steady, there is now a relatively complete mockup with a footprint of 8"x16". Harald bottled his brown porter after sitting in the back for a few weeks, and instantly got to brewing another batch.
Meanwhile, at Queeg's secret lair, he wrestled with the greasy german tranny. Once it broke loose from the chains, we had to scramble to make sure it wouldn't run away on us. It did get a suckerpunch on Queeg's face, though.
I opened up the dynamo side of the hub looking for a zener diode to clip, which would de-limit the output of the dynamo. The output of a dyno hub is typically regulated at the above specs so it wont overpower an old filament bulb. Since I have something a little more powerful in mind, like some power LEDs, it would be useful to bump up the output and rectify the current. I was suspicious that half of the wave was being clipped, as the light just didn't seem quite as bright.
So once I hook a multimeter up to it, something suprising showed up. It turns out the specs are a lie! In the parking lot here I was able to acheive 14VAC at about 20 mph. Okay, that saves me one step and some trouble.
So the light I am using is a triple LED mounted in an MR16 housing (the kind found in most track lighting as a halogen bulb) with a rating of 12V AC/DC @ 7 watts. Two years ago it cost me about $20. Hooking it up to a power supply at 12V reads 360mA, or ~4.5 W. There is obviously some internal regulation happening inside the housing, and a quick inspection confirmed a SMT LED driver in the case.
I had the lamp in a housing using it as room lighting beforehand, and it was very bright. Early in the morning when I had the light connected directly to the dynamo, it reached peak brightness at about 15 MPH. I was not satisfied with the light output under AC current, which is what led me to build the bridge rectifier.
In the first iteration as a pure bridge rectifier, the output was ~16V. Cool! Adding some 1000mF electrolytic caps to the mix pushed the voltage up over 20. Im not entirely sure that would be bad for the LED, but I'd rather not take the chance. I found a suitable voltage regulator and after installing it at, now the hub seems to be stable at 12.2V
I tried a couple different arrangements of Caps (series, parallel, series and parallel, before and after the regulator). Guessing, I settled on two in parallel after the regulator so I dont push the specs on the caps, which are rated for 25V. I'll let you know the subjective results tonight once it gets dark.
Hub dynamo regulation circuit ideas
...so i haven't gotten a look at the paper copy yet, but Redbull Creation got a writeup in the November issue of Popular Mechanics and that means we might be in there, in tiny gray print, possibly under a bunch of other people.
Thought you should know.
Friday Update! There's a nice 4 page article but they don't seem to mention us. The barest corner of our see saw is visible in the background of the Donner Party photo. Not that I looked.
In case you haven't seen it, Plug Computers are tiny embedded servers that are usually about the size of a normal wall wart or power supply. We got a Sheevaplug dev kit from Globalscale Technology and gave it a go.
After quite a few false starts, we got ArmedSlack Linux installed and it has now replaced our old eeepc as one of the shop servers. Check out the new equipment cabinet, now with cooling:
The plug computer is the white thing on top, with the blue 23b sticker. If you'd like to set up a Sheevaplug for your DVR, monitoring server or whatever, we've documented everything here:
First off, we needed to get the manual for it. Fortunately, the Lincoln manual already had the pin-outs for its accessory connector, and Miller is very good about letting you download their old service manuals.
From the manuals, it appeared that the Spoolmatic needs a 35V DC power supply, a realy, and a simple RC circuit to provide a power-on delay for the motor. The Lincoln seems to just need triggering, which we can do with a second set of relay contacts.
The next problem was finding the right MIL-SPEC connectors. The one on the Miller was a 4-pin AMP, and I was able to locate this fairly quickly on Digikey, as most of these are type 97. FYI, the female pin part is:
The 12-pin Lincoln connector was a little harder to track down, but I made a guess that it's also an AMP and found it as:
Next, I made a quick board layout in Eagle CAD and etched a board using Fab in a Box and a laser printer:
And here it is stuffed:
So far, I've got it activating the welder and spool gun. The next step is to see why it isn't auto-sensing spool gun vs. MIG gun. But this isn't bad for one evening of progress.
Details are below:
Saturday, August 27th · 7:00pm
418 E Commonwealth Ave #1
Join us for the next Hacker Potluck at the 23b Shop. Saturday 7/23,
Open invite, feel free to tell a friend. It's a potluck, you know the
deal by now, yes?
Congratulate us on our recent win, and check out our new welder. Get
there early (any time after 3:00pm) , and we'll be doing a welding
Check out our gallery pics:
Other team's photos:
Team Alpha 1 Labs
And here are some newspaper articles:
O.C. Register (article about 23b entry)
Well, it paid off. I think. We're not entirely sure when they Likes are tallied but as of right now, AFTER the official close of the contest, 23b has 435 likes, i3detroit has 385. Nobody else is even close. If you still haven't voted, drop in and vote please. It's possible that this isn't quite over and every little bit counts :)
Thanks to the 435 of you that have helped us out. as promised, arclight will be giving free welding lessons to the people who liked us! He's going to find out about this as soon as he get's back from new york, wont that be nice?
For those that missed it, Red Bull sent out an invitation to Hacker Spaces to participate in a "making stuff" contest this Summer. Well, we entered on a whim at the last minute, and made it into the finals. So Red Bull is paying for us to go to New York for the big competition. Check out:
Today, Adam and I decided to do a last-minute foundry run. After last week's session (where we got one usable casting and about 10 pounds of fail) we got some new Olivine green sand from IFSCO in Commerce, CA.
This went much better. It took a while to get the sand dialed in, but we got several good castings.
The things we changed were:
-Purchased some Sodium Silicate and tried making professional cores
-Changed out the parting dust from flour to baby powder.
-Made new flasks
Adam is working on a Gingery lathe. The pics below are of making one of the cast Aluminum feet.
Filled molds ready to be shaken out:
Adam K. readying the sand molds
Arclight pouring hot Aluminum
And the finished product:
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.