The Big Think

May 31, 2016

Education

Filed under: Education — jasony @ 8:13 pm

Oberlin students say bad grades are getting in the way of activism:

“The New Yorker claims that more than 1,300 students recently signed a petition calling for the college to eliminate any grade lower than a ‘C’.
The students complain that it is not fair to grade them on their performance in class because they are so distracted by their activism…

…Last December, for instance, Campus Reform reported that student protesters had submitted a list of demands to their school’s president, including one calling for hourly monetary compensation for activists.

Earlier this year, activist students at Brown University voiced similar complaints, saying their schoolwork was interfering with their activism efforts.”

May 30, 2016

R2 – First Welds!

Filed under: Uncategorized — jasony @ 9:06 am

I met with Keith at Techshop yesterday for a 2 hour TIG welding master class. The guy is a riot of old-school enthusiasm and energy and I learned a lot from him. At the starts of the session I showed him my practice welds (I have a plate of about 20 welds on it that I’m particularly proud of) and wanted to spend the time taking about the pieces I’d brought and how I would eventually weld them together. What does he see when he sees those pieces? How does an experienced welder view a part? What’s the best approach for clamping? What about cool down time?

He’d have none of this “planning” stuff.

Instead, he looked at my test piece with approval, said “you can weld”, then chucked the test piece aside, grabbed the horseshoe pieces, and said “you’re going to weld this…. right now”.

And so I did.

He did the first couple of tack welds to hold the part together, get things heated up (welding a part is much easier when it’s already hot), and generally give me a start, and then he handed me the torch and we went after it. If I made a slight mistake he jumped in and either corrected it or talked me through how to fix it, and then handed the torch back to me.

Over the next two hours we welded up the horse shoe and then aligned and welded up the center ankle. I feel really good about how things went, especially considering the fact that I didn’t think I’d be working on actual parts for a few weeks. Keith is a “get ‘er done” sort of guy that encourages students to jump in there and start even if they don’t know everything. I’m much more careful about parts that I’ve spent months and lots of money making, but Keith is kind of a whirlwind that you just get sucked up behind.

The hardest part of the process was the angles and orientation. I’d been planning on carefully laying out the parts so that the joint to be welded was flat and parallel to the ground. That way I could approach the weld exactly like I’ve done each weld in practice. Keith’s attitude was this is real welding! and he’d proceed to put the joint at some funky angle and then challenge me to do it. Sideways, angled, even upside-down at one point! Really awkward and tough stuff. And this was on my actual parts! It really freaked me out, but like I said, he was there to correct things when I got them wrong.

And boy,did I ugly up some of the welds. Black, splotchy, butt-ugly welds. They’re strong enough, sure, but I’ll be spending some real quality time with the grinder once I clean them up. Keith kept saying “don’t worry! You’ll improve!” and I kept saying “but I could do this if we could just lay it out flat!”. He’s respond with “no way! This is REAL welding!” and then make me bend myself into some impossible orientation to get ‘er done. It was stressful, but I learned a lot from the experience. The chief thing I learned was that, unless you completely destroy the metal with heat, you can fix just about any bad weld. Keith didn’t do much cleaning or anything and still managed some good welds. We talked pedal control, getting REALLY close to the puddle (he was probably 1/32nd from the weld with the tungsten!), using a different tungsten (I’d been using the red 2% thoriated and he recommended the purple 2% seriated because it holds a cleaner and more consistent arc), speed, power (150 amps!) and other stuff.

I got a couple of decent tingle/zaps from the setup when my left hand got soaked with sweat inside the glove. With 150 amps of 6v electricity, even with protective gear, getting a damp hand in the current can cause some discomfort. It didn’t hurt as much as it was just unpleasant. Some tingling like touching a 9 volt with your tongue. Lesson here is to take breaks and make sure you’re dry. But that’s hard to do when you’re in the Keith whirlwind.

So I’ve got both horse shoes welded and the center ankle. I’m going to mill up a special part for the center ankle to reinforce the mounting holes. I don’t think the 1/8″ of aluminum there is strong enough if R2 hits a good bump. It’s technically an “off spec” part but it’ll be hidden underneath R2 way up inside along the bottom of the frame so I don’t care. Better that than have the whole ankle shear away. An extra 1/4″ of aluminum there should work nicely.

No pics on these parts yet. I can’t have my expensive iPhone in my pocket when I weld lest I zap it. And usually I’m so tired and grubby after a 4 hour session that I just want to get home and take a shower. I’ll take pics later.

Next step is to do the outer ankles. I feel really good about my approach now that I’ve watched Keith do it. Then I’ll weld up the leg assemblies and then maybe the feet. I’ll leave the battery boxes for the end since they’re going to be a real challenge to align and tack up without them warping all over the place. Slowly, slowly.

Onward!

May 23, 2016

R2 Aluminum Pile

Filed under: The R2 Project — jasony @ 9:29 am

That’s a great big old pile of aluminum:

IMG 2199

What you’re seeing here are all the aluminum parts I’ve milled, water jetted, lathed, and otherwise mashed up since last September (really since about February). 

Starting from the left are the leg boxes, horseshoes, ankles (bottom left), battery boxes, and ankle bracelets. Then on the right hand side are the feet (all spread out on the table).

I opted to let Big Blue Saw cut the water jet files for the feet since it wasn’t that much of a premium and since they would replace any pieces that were messed up. Overall I think this was the wiser course even if it wasn’t immediately cheaper. It was cheaper in the case of the water jet making a mistake (something that happens about 10% of the time at TechShop). Even so, there are 90+ pieces of the feet (center foot and two outer feet) that have to be welded.

And oh, the welding. Most of the above pieces except for the horseshoe at the upper left still need to be TIG welded. There are 174 remaining pieces that will need to be cleaned, aligned, clamped, and TIG welded. I’m not sure of the total length of welds but it’s a lot and I’m sure I’ll be at it for months. Fortunately, except for two pieces, all of the machining and cutting is pretty much done for this year. Once the feet are welded I have to cut some pipe to size and then lathe, cut, and mill out a weird piece. Then once all of what you see here is done I’ll begin designing and cutting/welding the foot motor mounts. I think I’m going to do those custom but I’m still thinking about it. That’s for later.

My goal is to finish all of this by September but I still don’t have a good handle on how long the welding will take. I’m going to put in a few more 4 hour sessions practicing before I try and tackle an expensive-to-replace part. I’m going to hopefully get a one-on-one lesson with Keith at TechShop this weekend. He’s the good welder from my previous posts (one of the best in Austin). Then I’ll go through the pile of parts and start welding up assemblies from easiest to hardest, thereby gaining experience as I go. I suspect the battery boxes are going to be the hardest so they’ll be last.

I’m thinking that I’ll end up missing my September deadline as things progress since I haven’t even included time to correct the leg boxes on the mill (long story for a future post), drill and tap holes for mounting the horseshoes, drill out the ankles and install bushings (no idea how to do that), and probably spend two or three long sessions making the funky curved parts for the outer feet. Oh, and I also need to research how to remove anodization with a lye bath. Got some industrial strength lye (and a pile ‘o protective gear) to remove that but I’ll need to do a practice session on some scrap to make sure I have the procedure down correctly. 

Then it’s on to the foot motor assemblies, which I’m kind of looking forward to. I’ll need to commit to the motors (I’m thinking a pair of NPC2112 motors — they’re pricey but they represent “real” robotics motors instead of hacked up scooter motors). I’ll get those soon and then start designing the motor mounts. The feet need to be welded up first, though, so that I can make sure that I have enough clearance inside the shells.

Going to TechShop this morning for a 4 hour TIG practice session. I’m running out of scrap and will probably drop by Metals4U and get some .125” pieces (hopefully from their scrap pile) to continue practicing.

May 12, 2016

Harvard’s clueless Illiberalism

Filed under: Politics — jasony @ 8:54 am

Harvard’s clueless illiberalism – The Washington Post: “Touring early America, Alexis de Tocqueville marveled at the people’s propensity to form associations for every purpose under the sun: ‘religious, moral, grave, futile, very general and very particular, immense and very small . . . to give fêtes, to found seminaries, to build inns, to raise churches, to distribute books, to send missionaries to the antipodes.’

Associational proliferation buttressed individual freedom, Tocqueville believed. As he explained, private groups are nimbler at orchestrating cultural and social life — ‘maintain[ing] and renew[ing] the circulation of sentiments and ideas’ — than government could ever be.

States ‘exercise an insupportable tyranny, even without wishing to, for a government knows only how to dictate precise rules; it imposes the sentiments and the ideas that it favors, and it is always hard to distinguish its counsels from its orders,’ he wrote.

Harvard University’s administrators should read Tocqueville’s book ‘Democracy in America.’ Their institution is not, strictly speaking, a state — it’s more of a state within a state, up there in Cambridge, Mass. In every other way, the school’s new crackdown on fraternities, sororities and a local variant, ‘final clubs,’ epitomizes the clueless illiberalism against which the French sociologist warned.

Harvard has concluded that, in response to sexual assault and other manifestations of gender inequity, it must reform campus culture. Single-gender social organizations are unavoidably discriminatory, President Drew Gilpin Faust noted, ‘in many cases enacting forms of privilege and exclusion,’ contrary to what Harvard stands for.

Being private, self-funded and, technically, off-campus, the groups can’t be banned; but they can, and will, be discouraged and stigmatized. Starting with the class admitted in 2017, no student members of single-gender fraternities, sororities or final clubs may hold ‘leadership positions’ in Harvard’s hundreds of officially ‘recognized’ undergraduate organizations. Nor may they apply for fellowships, such as the Rhodes and Marshall scholarships, that require an official college endorsement.”

Read the whole thing.

It’s interesting to me that suddenly the various groups who have been in favor of limiting freedoms they don’t agree with have suddenly become outraged when their own particular ox is up for goring. This has been the (sadly missed) point of the voices who have spoken out against Social Justice Warriors and anti-free speech people lately. What’s become of “I don’t agree with what you say but will defend to the death your right to say it?”. It’s been flushed down the PC toilet. And now the next step is to deny under penalty of economic sanction the freedom of association that we take for granted in America.

And just so I preempt the people would would say “but Harvard is private! They can do whatever they want! Freedom of association is only a government thing!”: you don’t really get the bigger point here? But don’t worry, your ox is up for goring next.

Should all locks have keys? Phones, Castles, Encryption, and You.

Filed under: Technology — jasony @ 8:25 am

Should all locks have keys? Phones, Castles, Encryption, and You.

May 11, 2016

TIG Success!

Filed under: The R2 Project — jasony @ 7:06 pm
Best day TIG welding so far. I went through five filler rods (about 30′ of material) and didn’t mess up my tungsten once. Got some really nice welds laid and also ground them down flush so they look nice and pretty.

I did a drop test on the dummy part and determined that I need to grind the channels between the layers a little deeper to get better holding between the layers. But otherwise I’m actually ahead of where I thought I’d be after only 12 hours of practice! Very encouraged.

TIG Welding Practice.mov

I spent 10 hours at TechShop today. 4 doing welding practice and the rest grinding and prepping the parts for welding. Really successful day.


May 10, 2016

R2 Outer Ankles

Filed under: The R2 Project — jasony @ 9:19 pm

I’ve spent the last few days (post concussion) designing and tweaking the design for Artoo’s Outer Ankles. The water jetted layered .25″ aluminum trick is working nicely. I still have to TIG weld everything but Keith was able to TIG the .125″ horse shoes a few weeks ago and it worked well.

Today I checked out the water jet and spent four hours cutting 21 parts for the outer ankles. I had to remake one part since I didn’t clamp down the metal well enough and the edges were really jagged and messed up. I could have maybe dealt with it while welding but I decided to spend the extra three bucks and just cut another one. Total price for the outer ankles was just over $50 for the water jet time. The reason it took so long (4 hours!) was because I cobbled together a bunch of scrap aluminum that I’d used on other parts. I got all the parts in on scrap! This saved me probably $50 extra dollars in aluminum and let me clear some cruft out of my locker. Keep in mind that I’ve now done all three ankles (one center and two outer) for about $120. If I bought these over the internet from one of the suppliers they’d have cost me over $900!

In fact, I just looked at my master budget sheet and if I just look at Year 2: Legs I can get a sense of just how much I’m saving making the parts myself. Here’s the going price on the internet if I just bought the aluminum leg parts that I’ve made so far:

Leg boxes: $900
Horseshoes: $450
Ankles: $900
Ankle Bracelets: $30

So if I’d have just laid down the dough I’d be looking at almost $2500. I’ve spent less than a fifth on the legs. From here I still have to do the feet and the drive mechanisms, which would add another $1800 if I bought them…. and which I’ll get for an even better fraction.

So yeah… building it yourself is definitely the way to go, and the skills you pick up can’t be beat.

Speaking of which, I’m into my TIG welding practice. I’ve spent 8 hours at the TIG and can just now barely succeed (sometimes) at not embarrassing myself. But if I can just break through to reliably making two or three inches of halfway decent welds then I’m home free. I’m saving a bunch of offcuts and scraps of aluminum in various thicknesses to practice on. My plan is to make all the parts for the legs– horseshoes, ankles, leg boxes, feet, etc– but not weld any of them. Once the parts are made I’ll then dig in for several weeks of slow and methodical welding on each part. All I have to do is one or two inches at a time, let things cool, then repeat. I figure I probably have 200 feet of welds to do. It’s gonna take a while.

But slow and steady wins this race.

I may not be the most talented guy at any particular thing, but what I lack in ability I make up for in sheer stamina. I figure if I can stay with this R2 build for a half decade then really nothing is outside of my grasp.

Onward.

May 9, 2016

All The News That’s Fit To Tell You

Filed under: Uncategorized — jasony @ 5:54 pm

Former Facebook Workers: We Routinely Suppressed Conservative News: “Several former Facebook ‘news curators,’ as they were known internally, also told Gizmodo that they were instructed to artificially ‘inject’ selected stories into the trending news module, even if they weren’t popular enough to warrant inclusion—or in some cases weren’t trending at all. The former curators, all of whom worked as contractors, also said they were directed not to include news about Facebook itself in the trending module.

‘I believe it had a chilling effect on conservative news..I’d come on shift and I’d discover that CPAC or Mitt Romney or Glenn Beck or popular conservative topics wouldn’t be trending because either the curator didn’t recognize the news topic or it was like they had a bias against Ted Cruz.’

The former curator was so troubled by the omissions that they kept a running log of them at the time; this individual provided the notes to Gizmodo. Among the deep-sixed or suppressed topics on the list: former IRS official Lois Lerner, who was accused by Republicans of inappropriately scrutinizing conservative groups; Wisconsin Gov. Scott Walker; popular conservative news aggregator the Drudge Report; Chris Kyle, the former Navy SEAL who was murdered in 2013; and former Fox News contributor Steven Crowder. ‘I believe it had a chilling effect on conservative news,’ the former curator said.

Other former curators interviewed by Gizmodo denied consciously suppressing conservative news, and we were unable to determine if left-wing news topics or sources were similarly suppressed.

Managers on the trending news team did, however, explicitly instruct curators to artificially manipulate the trending module in a different way: When users weren’t reading stories that management viewed as important, several former workers said, curators were told to put them in the trending news feed anyway.

…When stories about Facebook itself would trend organically on the network, news curators used less discretion—they were told not to include these stories at all. ‘When it was a story about the company, we were told not to touch it,’ said one former curator. ‘It had to be cleared through several channels, even if it was being shared quite a bit. We were told that we should not be putting it on the trending tool.’

‘We were always cautious about covering Facebook,’ said another former curator. ‘We would always wait to get second level approval before trending something to Facebook. Usually we had the authority to trend anything on our own [but] if it was something involving Facebook, the copy editor would call their manager, and that manager might even call their manager before approving a topic involving Facebook.’

I’m waiting for the online counterargument to go from “this couldn’t possibly have happened” to “well, all news is biased so this isn’t really a big deal”.

What’s a big deal is getting a filtered view of reality when you think you’re getting the straight information, and trying to make decisions based on that assumption.

All the people in favor of this sort of corruption are only in favor of it because it helps their side. Give it to me straight and let me make up my own mind. 

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