Sunday, May 30, 2010

Tag Sale Loot

Every six months, my parents' church holds a tag sale. I managed to drag myself out of bed early enough to go today, and I got some really cool stuff.

I got a compass - the circle-drawing type, not the direction-finding type - to replace my old one which is sticky in some places and loose in others. This one is smooth in all places, and will be rather useful when drawing circles for nose cones and transitions.

I got a miniature flying pan, about 6" across with a 4" bottom. It has a rubber-coated handle for safety. And a little metal stand? How cool is that? I plan to use it for firey experiments, where I can burn stuff in the pan, or use a candle or alcohol lamp underneath.

I got a little keyhole saw, with a thin little footlong blade. Useful for cutting circles out of plywood.

Best of all I got a little electronic scale, runs off a 9V battery. 5 pounds capacity (actually 5 lbs 5.6 oz...) in 0.1 oz steps. That's 2270 (actually 2370) grams capacity in 2.83 g steps for you Canucks, Brits, and Aussies and other metric folks. Perfect for measuring rockets and such, so that I can simulate them more accurately. Especially nice for determining what size parachute to use for my larger rockets.

I also bought six books:

The Double Helix by James Watson. An account of the discovery of the double-helix structure of DNA and general comments on DNA, from one of the main men involved.

Dragon by Clive Cussler. A general techno-thriller in the Dirk Pitt series. With Japanese terrorists and a third nuclear bomb that never made it to Japan.

Red Phoenix by Larry Bond. A military thriller of a second Korean War. Doubly appropriate given the recent tensions over there.

Never Have Your Dog Stuffed. The first part of Alan Alda's autobiography.

The Elements of Color: a translated work authored by Johannes Itten. A treatise on color theory - very interesting.

Godel, Escher, Bach by Douglas Hofstadter. So much cool stuff on mathematics, music, programming, and art. It's as close as you can get to a complete liberal arts equation in one book.

Saturday, May 29, 2010

Demonic Orange

So, yesterday was an interesting day in AP Chem. We're done with all our learning for the year; the AP exam was three weeks ago and our last test was Monday. So, for the last 2 weeks of the year, we're doing some of the labs that we didn't have time for before the AP exam.

Yesterday, we did a lab with electrochemistry: fruit batteries. We were given strips of iron, copper, zinc, aluminum, brass, and lead; 3 oranges; and 1 lemon per group, plus our usual lab setup of a laptop with graphic program and a voltmeter interface.

After a little bit of data-taking, we found our answers. Two orange batteries of copper/zinc, one orange battery of aluminum/brass, and one lemon battery of aluminum/brass generated 2.78 volts - twice as high as any other group came. We believe this solution is more or less optimized given the available materials and limitations (no more than two electrodes per metal).

Then, we had extra time. A few of us got hold of a plastic knife (normally used to slit the fruits to insert electrodes) and went to town on the oranges. Here's my contribution, a positively demonic shrunken head / orange-o-lantern:

Thursday, May 27, 2010

Thesis Paper Day

I've got to write my entire second draft of my thesis paper for English tomorrow. My first draft wasn't great, so I had to cut it down to three pages and mercilessly edit those. Now, I've built it back up to over 6 pages (it has to be 5 to 7) and I'm almost done. With any luck, it'll be done by midnight, and I'll have statistics then.

It's currently over 2100 words. The original short story isn't much longer.

I did manage to get a little bit of rocketry done today - I primed the Orbital Transport. It needs a second coat to get all the nooks and crannies, but it's looking good.

Wednesday, May 26, 2010

More CATO 161 Pictures

Two racks of LPR rockets, none of them mine:
And me setting up the Sudden Mach:

Launch Report #38: CATO 161

Yes, another late post. Oh well. I have no no time whatsoever lately.

The weather was great on Saturday - hazy but no wind. The only frustrating bits were that there were a lot of kids around - three school groups totalling almost 60 kids - and that a lot of rockets flew right into the sun and were hard to spot.

My first flight was the L-13 on a C6-3; simulated altitude 500 feet. It was a bit squirrelly and wobbled during boost; I'll add some nose weight before its next flight. It recovered nicely on a 15" chute (repaired from last month's launch).
Second flight was the Mach Goon on a G115WT reload. Simulated altitude 3500 feet; simulated velocity 1250 fps (Mach 1.1+). Way to high for this field, but I was asked to specially and I got permission. The motor ignited almost instantly, and it ripped off the pad:

It took a sharp turn east at a few hundred feet off the ground; perhaps a fin split off or it spit a chunk of propellant. Stability was marginal in any case. It roared off at ridiculous speed, and I heard a crack which may have been it breaking Mach for a moment. I never saw ejection despite the loads of tracking powder, and currently it's lost. I got in contact with the owners of a nearby farm field where it may have landed; they said they'd keep an eye out for it. Nice folks.

Final flight of the day was the Sudden Mach on an E18-4W, simulated altitude 1350 feet.

The drogue was a 6" nylon chute; the main was 15". Al Gloer helped me (a lot) with the charge, and I set the Minitimer 3 to 25 seconds - approximately 400 ft AGL at deployment.

It ripped off the pad rather nicely. I love the E18 reload.

It deployed the drogue right at ejection, but then the whole thing came apart, connected only by the Kevlar shock cord, and the charge never fired.

Turns out, it's hard to glue stuff to Blue Tube. The spacer rings had both stripped right off their couplers at ejection - easily repairable.

I'm not sure why the timer didn't fire the charge; perhaps it was mounted too loosely in the avbay. In any case, that's an investigation for another day, and I'll explain it further tomorrow.

Total was three flights, three rockets, three motors. Total of 188.4 Ns - one of my highest one-day totals.

Tuesday, May 25, 2010

Tripoli certifies the first RATTWorks Tribrid motors

Yeah, I'm a week late, but this is so cool I couldn't pass up posting.

Tripoli Motor Testing has certified the first Tribrid motors. They're a special type of hybrd motors that have two types of fuel, alcohol and ABS plastic, along with the nitrous oxide (N2O) oxidizer.

First, an igniter grain ignites, causing the nitrous to burn with the ABS, in normal hybrid mode. Then, the alcohol ignites, and it's running in the higher-thrust tribrid mode. Finally, the fuel grain runs out and the N2O and alcohol burn in bipropellant mode until burnout. RATTworks has an excellent tutorial.

Both of their first two tribrids are mid-K motors in the standard 64mm (2.5") hardware.

The first tribrid is the K350TR-P. It's a 45% K at 1861 Ns, average thrust of 453 N, max thrust of 863 N (194 lbs). Burn time is 3.89 seconds; thrustcurve info and thrust curve are available.

The second is a longer version with a different liquid injector assembly, the K600TR-P. It's a 70% K at 2170 Ns, average thrust of 561N over a 3.67 second burn time; max thrust of 1223 N. Thrustcurve info

Rocketry Planet article
Thanks to Dick Stafford for the tipoff.

Sixteenth Match

Sixteenth and final match of the season was yesterday against Griswold. We won 6-1 very quickly; only Rahul had a tough match. (Griswold has one good player and everyone else stinks). I won 6-0 6-0, to end the season with three bagel sets (6-0) in a row.

Final season statistics:

Team: 13-3, ECC Medium Divison co-champions

Me: 12-3 singles (11-3 @ 4 singles, 1-0 @ 3 singles)
0-1 doubles (0-1 @ 3 doubles)

6 bagel sets (2nd on team)

ECC individual championships are this Thursday and Friday but I likely won't be playing; even as division champs we can only bring three singles guys and I'm low man on the totem pole. States are next week at Yale.

Sunday, May 23, 2010

Martin Gardner

One of the giants of popular mathematics passed away yesterday. The great Martin Gardner died in Norman, Oklahoma at 95.

Even though he did not understand calculus and never took a mathematics course past high school, he "more or less single-handedly renewed and nurtured interest in recreational mathematics in North America for a large part of the 20th century" (Wikipedia). He introduced dozens of new and unusual concepts to the public, from irregular Penrose tilings to John Conway's Game of Life to fractals.

He was also an accomplished magician, a profilic writer in multiple subject areas, a noted literary critic,an expert on Alice in Wonderland, a skeptic and debunker, and more. The man was simply amazing. I've read a lot of his works and been very impressed.

Mr. Gardner, you will be missed.

Thursday, May 20, 2010

Fifteenth Match

I know, I know, enough with the tennis posts already! This was the next-to-last match, though, so tennis posts are almost done for the next 10 months.

Today was against Lyman. They're in a smaller division than us and not terribly good, but they still put up a fight. Our #2 singles out was out sick, so I moved up to 3 singles and a freshman, Jason, played 4 singles. He's decent but not quite ready for singles, and he unfortunately lost.

I played a pretty tough kid at #3 singles. He had a fast, accurate serve and lots of sidespin on his shots. I once again found myself down 3-0 within minutes. And then I just started playing better - returning his serves, nullifying his spin, getting him frustrated. I won 5 games in a row, putting me up 5-3, and won the set 6-4. The next set, he was frustrated and did not play well; I won that set 6-0.

The team won 5-2. Team is 12-3; I am 11-3 on singles. Last match is Monday.

Wednesday, May 19, 2010

Fourteenth Match: We are the Champions

Fourteenth match today - last match in our division. It was against Windham, who we beat 4-3 earlier in the year.

I played a different guy than before, and this one was harder. He had a fast, accurate first serve that got in better than half the time. He quickly got up 3 games to none. I talked to my coach and he gave me a few pointers, and I came back to being down 3-2, then 4-4, then 5-5, then 6-5. Finally I pulled it to 6-6 and forced a tiebreaker, which is fairly quick and played to seven points. He won it 7-2 - all that work for nothing!

But, I came back to win the second set 6-2. I played better - I started returning his serves, hitting shots to his backhand, and forcing him to make mistakes. I then got up 5-2 in the second set.

By this time, all other matches except 2 doubles had finished; we were up 3-2. All my teammates were cheering, which was pretty awesome. The last game took almost 10 minutes - lots of monsterously long points - but I won it. 2 doubles won, too.

This was our last match in our division, and we've only lost one match in-division - our first match versus Bacon - so we tied them for ECC Medium Division Champions. First time in 10 years. How cool is that?

Tuesday, May 18, 2010

Sudden Mach Progress

I'm getting more and more done on the Sudden Mach. Today, I mixed some epoxy clay and fixed the eybolts into the ends of the bulkheads for the avbay, and used the epoxy to close the open eyes on the eyebolts. I also attached one of the two rail buttons.

Here's a picture of all the parts together.

Tomorrow, when I've got a little time, I will take the two loose basswood disks and make the 'sled' for the timer. It'll incorporate the switch,, so that I can turn the electronics fully on/off with just one switch.

My mom also fixed two parachutes that were damaged in the last launch, by patching the burn holes. They're all ready to go for the launch on Saturday. The Sudden Mach should be ready by Saturday, so long as I start gluing the fins tomorrow.

Goddard L-13 Pictures and the Reaverized Multi-Goon

First, the nice paint job: The Goddard L-13, fresh from 4 shiny masked layers of paint:

The red side actually only takes up one quadrant, but that's hard to see from the pictures.

Next, the ugly: the Multi-Goon. I tried to make the aft end look like it was glowing from the heat of the engine, but instead it dripped and stuff. So, now I have the Reaverized Multi-Goon.

For more on Reavers, consult Wikipedia or the Firefly wikis.

Thirteenth Match

Thirteenth match was yesterday against Montville. I played a different guy than I did in our previous match against them (my first singles match), and this one was easier to beat. He didn't have a hard serve nor lots of spin, though he did have some good drop shots. He was also one of the nicest opponents I've played - no swearing, racket-throwing, or obvious signs of anger, nor rude gestures like trying to hit me while giving me the balls for my serve.

I won 6-2 6-1. The team won 5-2; 1 and 2 singles won easily, 2 and 3 doubles won harder matches, and 3 singles and 1 doubles lost. The team is now 11-2; I'm 9-3 on singles.

Monday, May 17, 2010


I just finished watching Juno with my sister. Okay, not 'just', it was an hour ago. And yes, I know I'm two years behind the times.

But it is an utterly amazing movie. Funny, yet poignant (did I spell that right?), and it's the first movie I've ever seen with a smart, self-aware, and not utterly helpless main character. See my previous thoughts on that subject here.

It's also eminently quotable ("Yo yo yiggity yo" is my greeting for a while), and I love the songs. I also love the opening sequence - Juno (Ellen Page) walking through her town, with everything but her drawn as simple line drawings.

Saturday, May 15, 2010

Marathon Building Session

I probably got more building done today than I have in any single day in the past 6 months.

Most of my work was on the Sudden Mach. I Finished cutting all the tubing for it - forward, avbay, and aft sections cut to length, plus the two spacer rings on the couplers. I glued the retainer rings onto the couplers and cut the couplers to length. I sanded the edge of the forward section down to form a smooth joint with the nose cone.

I test-fit all the avbay components together. With the exception of one of the two bulkheads, which I sanded to shape and glued together today but didn't have time to drill, every part was ready for a rough fit. I cut the lenght of all thread in two to fit the length; all the nuts fit perfectly, and it holds it all together.

I also cut the Kevlar shock cord and tied the ends to prevent fraying.

There's only four major things remaining to do for the Sudden Mach. First, attach and reinforce the fins. Second, build the 'sled' that holds the timer inside the avbay. Third, drill the holes in the last bulkhead plate and attach the eyehooks to both with epoxy clay, and finally, use the epoxy clay to attach the shock cords to the body tubes. Then, it'll be ready for a test flight next Saturday.

I did a bit of work on the Multi-Goon as well. I glued on bits of plywood to the 5x13mm and 3x18mm motor mounts for better retention.

Once the primer was dry and sanded on the L-13, I applied two coats of paint. The first was an all-over coat of silver, then the second was a coat of medium grey, masked off for scale-detail stripes. It looks really nice. Tomorrow comes light grey and red.

Pictures coming soon.

Priming the L-13

I finally got around to priming the L-13 yesterday, now that it's nice weather one again. I also had the tail end of a can of automotive primer to use up. No pictures, sorry, but it came out nice. First coat of paint goes on later today.

Thursday, May 13, 2010

Eleventh and Twelfth Matches

...And thus ends a very disappointing week of tennis.

Monday was Waterford, one of the best teams in the league. I played against a guy with a nasty slice (sidespin + topspin) in swirly winds. And he was a total jackass - pushing me back with fast first serves, then trying to drop second serves in before I could run up. It's illegal to serve your second until your opponent is ready, which in my case means giving me time to move in. I lost 1-6 3-6; team lost 1-6. Only Rahul won with a looooong match - 3 sets - on first singles.

Today was New London, who we beat earlier in the season. They were missing a few guys who were on a band trip, so they only had 9 guys for 10 varsity slots. Guess who wins by forfeit? Yep, me. Everyone won except for 3 singles (ironically playing the guy I beat earlier). Team is now 9-3; I'm 8-3 on doubles and 8-4 overall.

Next week is 4 easy matches. I hope to win in all of them.

Wednesday, May 12, 2010

And I'm back to recursive posting again

I really don't like 'no time to post' posts. Cause they take up space, accomplish nothing, and they're recursive. But this is all the time I have tonight (and prolly tomorrow) so I'll be back on Friday.

Mike Dorffler

A few days ago came the sad news that Mike Dorffler, one of the giants of rocketry, has severe terminal pancreatic cancer. Dorffler started at Estes in 1969 and designed a number of famous kits, including the Cineroc (an 8mm movie camera mounted in a rocket looking down, and the Apogee Aspire and Saturn IB and V kits. The Cineroc even inspired NASA to put a similar camera on one of their flights:

It's suggested in the article to write to the Dorfflers, to let him know just how much he will be missed. Here is my contribution:

Dear Mrs. Dorffler:

I would like to express my deepest sympathy for you and your husband. It saddens me greatly to hear of his illness. Regretfully, I've never had the chance to meet him, but I've seen so much of what he's done for rocketry. His designs are legends, and I consider myself lucky to have been inspired by him.
Thank you for allowing all of us to share the benefits of his work. He is in my thoughts every day, and I wish both of you the very best.

Monday, May 10, 2010

New Commenting Policy

I've been getting a lot of spam comments lately. Chinese spam, with cryptic messages in English or Chinese, with lots of links to (presumably) dangerous sites with link-adresses that sound like adult sites.

Not exactly what I want on here. So, now all comments will be moderated be me before publishing. I usually check multiple times per day, but no guarantees. This also means I'll be more prompt about responding to comments from legit users.

Sunday, May 9, 2010

Building progress

I haven't made any huge progress, but I've gotten bits and pieces done with a few rockets:

I've been doing bulkheads for the Sudden Mach's aviatronics bay. I made one test bulkhead out of basswood, to make sure everything fits right. Now I'm cutting parts out of 3/16" plywood - 4 disks for the bulkheads, and more for the 'sleds' for the electronics to fit on. Lots of cutting and sanding and frustration. The first 2-piece bulkhead is almost finished, though.

The 18mm cluster motor mount on the Multi-Goon got burnt last flight, mainly because the balsa block holding the mount against the engine hook squished and let the mount partially slip out. The first thing I did was to scrape off the balsa and replace it with a piece if plywood that won't burn as quickly nor squish. Once that dires, I'll coat the whole thing in wood glue to protect it from the ejection charge, and then it'll be ready to fly in two weeks, probably on 3 B6-4s.

Misspelling 'Amateur'

I'm bored, so I'm going through the keywords that brought you-all here via the Google Analytics service. Very interesting, actually, to look at - anonymous visit stats and keywords. Like how someone included the ö with umlaut over it when searching for "möbius capacitor". Or how about 10% of my hits are from people looking for, um, 'adult' sites.

But, perhaps the most entertaining is the number of ways folks find to misspell 'amateur':


Friday, May 7, 2010

Sudden Mach Drag Race

I've now got an offer to drag race the Sudden Mach. Jim Hendricksen of ICBM (Tripoli SC) is offering his Blackhawk 29 against the Sudden Mach, motor of my choice, as long as we both manage to make it to NERRF in June.

It should be a lot of fun. The Sudden Mach is designed to drag race the Blackhawk, and it should win - it's somewhat lighter, so it'll get off the pad first.

Now I just have to finish the rocket in 2 weeks for its test flight at CATO 161,and then secure transport to NERRF.

Sudden Mach Fins Cut

I finally got all three of the Sudden Mach fins cut and sanded. They're high-quality 1/8" basswood. The long edge is 17 cm (6.7") long.

Tenth Match

Match yesterday against Fitch. Another revenge match; they beat us before.

I didn't do great. I lost the first set 3-6, then got up 4-0 in the second. But I only won one of the next 8 games and I lost that set 5-7, even though a numebr of my teammates were rooting for me. I wasn't feeling too good.

But then, just after I lost, 3 doubles finished. They won. Turns out, so did Rahul and Calvin at 1 and 2 singles, and 1 doubles as well. In other words, we won.

So now I don't feel near as bad. Also, I had an incredible shot. I was at the net returning a volley, and I sent a brutally fast shot straight down the middle. Straight at him. He ducked, but not fast enough, and it nailed him above the ear. He was okay, though. And it made me feel good. I'm so mean.

Wednesday, May 5, 2010

Ninth Match

Match at home versus Bacon today. This was a blood match; they humiliated us in the first match of the season and we wanted revenge.

And we got it. Team won 5-2. Not only did 2 singles and 1&2 doubles win as before, but 3 doubles (where I was before) got the win and won won as well.

I personally won 6-2 6-1. The guy I was playing (like almost all I play) had a strong serve that he couldn't get in. His second serve was very weak, so I'd run up, hit it deep, and then I could stay at the net because he wasn't able to lob it over me.

Team is now 7-2 and set to challenge for the league Medium Division title. We have a real tough match against Fitch tomorrow.

Tuesday, May 4, 2010

Eighth Match

Yesterday, versus Killingly. The day started out rainy but dried up, and it only stopped threatening rain halfway through the match. The courts were msotly dry, but one side had some slippery slime behind the back line near the fence.

The first set was hard. Neither of us could break the others' serve; it went back and forth but he eventually broke my serve - won the game even though I was serving - and he won the first set 7-5.

I broke his serve to start the second set; my coach suggested I hit deeper shots and that certainly helped. On my serve, we had a long deuce point that went back and worth until I finally won it. After I broke his next serve, I was up 3-0, and he fell apart. He was mad because I don't play hard and fast like he wanted to; he kept getting tripped up by my slow, deep lobs and short drop shots. He yelled at me, intentionally lost a few points, hit balls back to me hard after points, etc.

Third set I won 6-2. He was extremely angry for no reason other than that he was losing. He even said some things that were rather unchristian for a guy named Christian.

He wasn't a lot of fun to play against, but a win is a win, and hopefully I'll never see him again. Team won 6-1, so we're 6-2 now. Next match is today.

Monday, May 3, 2010

Minor Upgrades Complete

Added a few new labels, notably Professional Rocketry. Changed labels on old posts, corrected spelling and grammar. Updated profile. Added new blogs to list, and bettered the list of my best posts.

Labels have also been changed to a cloud from the older, plainer, bulkier list. Like / dislike?

I've put in Google Analytics code. It lets me see how many folks visit, from where, what they look at, how long they stay, and how they get here. Doesn't identify individual vistors, just gives me general facts and figures. That way I can keep my content as what all you folks want to see - no point talking about boring stuff, when it's apparently the APCP chemistry, dicyanoacetylene, and big motors you're after.

Since I've now got all the useful data with invisible, noninstrusive code, I no longer need the hit counter and map at the bottom, unless you want them. I moved them from the sidebar to the bottom anyway. Comments?

I've been thinking of changing the color from green, perhaps to blue of grey or something. Thoughts?

Ariane 5 Manual

The Arianespace Ariane 5 is one of the largest space boosters around. 151 to 170 feet (46-52m) tall, weighs 780 tons at liftoff. Capable of lifting 10 metric tons to geostationary orbit, or 20 metric tons to low earth orbit.

I now have the user's manual.

It's 238 pages, and you can get it for free in pdf form here.

I think it's the largest thing in the world with a user's manual. There's not a lot of, ya know, skyscrapers and aircraft carriers that come with a single manual. I may, in fact, have to print this out someday.