Monday, August 30, 2010

Space Truckin'

Courtesy: Pirate Art Institute

I loved this painting the first time I saw it.
It was an illustration for a short story called; Ride to Live, Live to Ride. The story was about a biker who was a high-iron contractor doing orbital assembly, but ends up being a hero. It appeared about 20 years ago in Isaac Asimov's Science Fiction Magazine. I've long since lost
track of the issue, author and artist.

My brother Keith photographed and printed it for me. Some cleanup was done at the time with ink and brush. I had a grandios plan to screen print parts of it on layers of plexiglas, for a 3D effect. The back layer would've had the stars engraved and sandblasted into it. The stack would then be mounted in a deep frame and internally backlit and edgelit [fibreoptic].

More recently I scanned it and we digitally cleaned it up again and then added colors to the Grateful Dead logo.

Friday, August 20, 2010

Sugar Motor Testing Pt.2, Getting Sweeter

Art Applewhite's Cinco38 Prototype
Pizza Hut

My Tide Wave version with ISP
38-360 case for comparison

Tide Wave on 1st sugar flight.
Using Ultra-White recipe.

Tide Wave pouring on the sugar
and spinning hard.

A big update to the previous post.
Since that test took place back in February I've burned 3 more sugar reloads in the test series. Since the test stand is still broken [the new guage I want for it aint cheap], I went ahead
and flew them in an Art Applewhite 38mm Cinco Saucer clone, my Tide Wave, or in Art's prototype Pizza Hut Cinco38.
Since it's 1st flight I've trimmed down the wavy edges twice on the Tide Wave. The spin under power was fine by me, but the spinning causes recovery problems. I've also flown the Cincos on an Aerotech G64W reload and an ancient and suspicious single-use Aerotech 320Nt H145 manufactured in 1988. These 2 motors definitely bracket the sugars below in the medium H category.

The motor that blew the stand had Bi-modal KNO3 [an inspecific mix of powdered and granular], my usual opacifier
1% Lamp Black, plus 1% Red Iron Oxide. A very fast recipe.
The next 2 are the same as above but with 8% Titanium shavings added for sparks. One had fine sparks, the other coarser sparks. The mildest recipe, nicknamed Ultra-White, uses granular KNO3 and 1% Titanium Oxide as a white opacifier. The only test recipe not burned yet is Ultra-Pink. Same as Ultra-White above but with the addition of 1% RIO on top of the TiO2.

So far, except for the wrong nozzle incident, everything has worked well. Ignition with my now standard Copper Thermite ignitors has been a non-issue. The RIO sure is messy stuff but it
really does improve pouring viscosity, just as other sugar cookers have noted. I didn't doubt it, but wow, seeing it happen is amazing.

At this rate, I'll have to make more test loads by the time the test stand is repaired.
Aw shucks.

Tuesday, August 10, 2010

Sugar Motor Testing [not all sweet]

Ignitor hookup.
Black crescent at bottom of guage
window is probable damage.

Instant On! Ignitor wires inflight,
Guage needle is still on zero.

Burnout. Foreground smoke
came out of guage face

Expelling a bit of casting tube.

Blackened guage guts hanging out.

In order to evaluate possible changes to sugar motor recipes, I developed a new shorter motor that would be more economical to operate. It helps that I was given a damaged reload case [Thanks Ray!]. My long motors use two 6 1/8" fuel slugs, unfortunately the short motor, after repair, only fits 5 1/4" of fuel. An even 50% would've been nice, but this is close enough, and it was a free motor.

Late last year I made 4 pairs of reloads, all physically the same,
but each pair has a somewhat different formula. All are moonburners since they burn twice as long. Eventually some will go to a thrust stand, but IMO, chamber pressure tests are initially more important. It's good to know what even works before tieing up [or risking] a high dollar digital thrust stand.

I made a new nozzle with a 3/16" throat that would be used with some of the new grains, especially the baseline formula. Being virgin territory, none of these reload kits have the
nozzles listed on the labels like I do with the larger mature reloads. On Feb, 20 2010, the morning of the test, I picked the new 3/16" nozzle and installed it with reload #1 rather
than with reload the mildest. Reload #1 was a hotty and should've been tested first with a 1/4" or even 5/16" nozzle. The motor survived the test but barely. Probably only because it trashed the guage and was blowing out both ends. As it is, it severely belled the nozzle washer and crumbled the corners of the nozzle where it was pressed into said newly angled washer. Despite the short foliage and limited dipersal angle, we never did find the polycarbonate guage window. There is evidence that the pressure guage was damaged previous to this test attempt.

The hydraulic test stand has been cleaned and is getting rebuilt. Besides the new & better guage, it's getting a grease fitting and a brake bleeder valve. Instead of filling the stand with brake fluid as before, I'm going to use grease. This will allow for easier transport of the stand and with a good grease gun I should be able to use the stand to pressure test motor case materials and other components.