Happy Holidays!

“I’m gonna see the world. Italy, Greece, the Parthenon, the Colosseum. Then, I’m comin’ back here to go to college and see what they know. And then I’m gonna build things. I’m gonna build airfields, I’m gonna build skyscrapers a hundred stories high, I’m gonna build bridges a mile long…”

-George Bailey

Blogs I Admire

Daniel Lemire is a professor at the University of Quebec. He writes REALLY fast code using all kinds of interesting tricks, mostly SIMD witchcraft.

Casey Muratori is a game developer possibly best known for his livestream Handmade Hero, in which he programs an awesome video game while narrating his progress in realtime.

Matt Pharr is a graphics researcher who co-wrote Physically Based Rendering, the first book to win an academy award! His blog is relatively new, but so far I’ve really enjoyed his series on the development of a new compiler during his time at Intel.

Paul Graham’s essays are super interesting. He’s a dotcom millionaire who now runs a silicon valley startup incubator called Y Combinator, and evidently he has nothing better to do than write cool philosophical essays.

Charles Guan builds combat robots and works on crappy vantrucks from the 80’s. His build logs are really detailed, and his narrative style is fun to read.

The Browser is an aggregator of interesting articles from around the web. They select articles that are well written and (usually) engaging. I like it because I end up reading long-form content that I otherwise wouldn’t, and a lot of the perspectives are different from what I typically encounter.

TIG Welding Aluminum

R.I. SHOP -- DO NOT REMOVE

I finally got around to trying out welding! The good news is, I haven’t burned out my retinas yet. The bad news is, it’s harder than I thought.

I’m using a Rebel EMP205 AC/DC welder set up for AC TIG. This machine has high frequency start to punch through the aluminum oxide layer and start the arc for you. That’s nice because I don’t have to learn how to scratch start the arc.

A VERY hot glue gun.

I have the TIG torch plugged into the (-) terminal on the welder and the ground clamp plugged into the (+) terminal. In welder world, this is known as “straight polarity” or DC Electrode Negative (DCEN).

I started out with some 1/16″ scrap that I found in the welding area. I had to chisel some epoxy off of it, and even after I wire brushed it, it was pretty dirty. With the welder set to AC TIG, 100A, 80% duty cycle, I spent 30 minutes zapping craters into my test piece and fouling my tungsten before I realized the gas wasn’t turned on! Once I found the secret regulator valve and turned on about 20 cfm of pure Argon, I was able to start and hold a steady arc with no problems (and fewer blast craters!).

My first welds are pretty awful, but after an hour or so I managed a few that look alright. I’ve since watched a few more youtube videos here and here. Next time around, I’ll spend a lot more time cleaning my parts with the wire brush and some acetone. I’ll also plug the welder into the 220v socket instead of the 120v outlet so that I can bump the current up past 130A. From youtube, I learned how to hold the torch more comfortably and how to extrude filler wire without periodic repositioning, and I can’t wait to try again with these changes to see if I can do any better!

Maybe next time…