HP-24 Project

Update 9 October 2006: A little bit of everything

It's been a busy couple of weeks, and I even managed to get some stuff done up at the shop.

On the weekend of 23/24 September, the kids and I took a leisurely drive over the crest of Highway 4, and then north to Truckee where we stayed the night. In the morning we had breakfast at the counterculture restaurant Squeeze Inn, and then drove on out to Air Sailing where Doug took the daughters for their first glider rides in his ASK-21. Both seemed to enjoy it; both stayed up for about an hour. After that we hung out for a while and then headed back pretty much the way we came.

The weekend of 30 September/1 October I had pegged to go see my second favorite Missouri cancer survivor Sheryl Crow at the Shoreline Ampitheater in Mountain View. But a few days earlier my climbing friends (the ones who flaked on me 16 September) prevailed on me to join them for a retry of the Royal Arches, so I piled that into the weekend as well. We rented a tent cabin in Yosemite's Housekeeping area for a base camp. Me, Jeff Hooker, and Majid Sabet climbed the 15-pitch Royal Arches route while Brigitta and the kids helped with the Yosemite Facelift, an annual cleanup event sponsored by the Yosemite Climbing Association. Their day was shorter than ours; we started at first light and got back on the deck just as it got full-on dark. However, this time we brought headlamps, so even as a pokey party-of-three we managed the whole route, including the 11 double-rope rappels, in about 12 hours. Contrast that to last year's adventure on that route, when we discovered on the descent that we'd forgotten both of our headlamps, and had to overnight at Rap 8 until it was light enough to see the rap anchors.

After another night at our base camp we sorted out our gear and split up, and I made it back to the Bay Area in time to see Sheryl Crow, John Mayer, and Marjorie Fair. That was a great show; I've always wanted to see Sheryl live. But the real adventure was getting to the show. I had to stop twice on the way to the venue to fix my car - once to install new wiper blades and then again to buy and install the alternator drive belt. Fortunately, I'd chosen a route that allowed me to limp over to Volpar, the only Volvo parts store in the Bay Area that is open Sunday evenings.

The weekend of 7/8 October found me back at the shop, working on the Radius machine. I've had lots of queries about why I'm bothering to make this huge complicated machine instead of using hotwired foam, fiberglass, and careful sanding to make form the control surface radii. I guess the answer is the same as that George Moffatt quote from the Sunship Game: "I just thought it would be faster the long way around." I know that this machine will make fast work of the 54 feet of radius that will want for doing, and I know that it is far more in tune with my strengths. This last weekend I built the height adjustment carriages for the hingeline support, built and installed the side frames the carriages slide on, and got the whole thing up on its own feet. Not bad for 18 hours of shop work. Now I need to build the transverse drive for the router carriage and I can start to cut some test parts.

On the evening of the 7th, we went into Murphys proper to see yet another concert; this time Train (the "Drops of Jupiter" band) and upstart Teddy Geiger. It looks like we might have one more concert coming up for the year; we're thinking of going to see Ok Go at their San Francisco show in early November. We first noticed these guys through their hilarious YouTube treadmill video for "Here it Goes." We bought their CD as sort of a lark, and now they're starting to get some airplay on our local pop stations.

In other news, Brad Hill has been making good progress with the winglet tooling; he's done with the winglet skin tooling and is working on the internal structure that supports it. He's finished the winglet root ribs, built fixtures to support the lift pins and moment stub, and is noodling along on the Glidair fuselage tooling while I figure out how to make the hat-section winglet spar that mates the moment stub to the winglet skins.

Also, sometime in the future I'm going to do a Composites Details update on making squishes for internal parts. Designing the squish for the hat-section winglet spar was a real eye-opener. Because hat squishes have both male- and female-molded surfaces, they can be somewhat of a topological brain-twister.

Here's some photos of the latest adventures:

On 24 September, Alia prepares to walk the ASK out to the runway.

Raen prepares for takeoff.

On 30 September, me belaying Jeff as he starts up the "Fingers in pin scars" at the bottom of the 5th pitch.

Majid anchors in for a rest at the top of the 9th pitch.

Jeff puts me on belay at the pendulum traverse on the 10th pitch.

Meanwhile, the kids don safety vests and help out with the Yosemite Facelift.

On 7 October, chopping out the little bits of tubing for the height adjustment carriages. Under the tap measure is my simple top-view sketch of the part. For stuff like this, I'll usually just sketch one view as a reminder, and keep the other perspectives in my head.

The finished carriages. Note that there's a right and a left. The tightening knobs are from McMaster-Carr.

The jig I zapped together to make the gudgeons that support the workpiece, and several of the gudgeon angle parts. This jig is a tool to make a part of a tool (the radius machine) to make a tool (the control surface plug) to make a tool (the control surface mold) to make a sailplane part (the control surface skin). I guess it really is sort of the long way around.

Here the jig is loaded for welding. A finished part is nearby. Rough, but workable.

Seven of the hingeline gudgeons.

On 8 October, chopping out the 2" tubes for the sideframes.

The sideframes with the top tubes jigged into place. Note the L-square in position on the far frame - these must be very close to a perfect right angle. Also note the two carriages standing by so I don't forget them. They are completely captured once I weld on the bottom of the sideframe.

The sideframes with the tops welded on and the bottoms jigged into place. Yup, I remembered to include the carriages. they're on the correct sides and right way up on both frames. Whew!

Most of the machine clamped together for the first time.

Welding together the dogleg at the middle of the backstay. This litle complication is so that the parts of the machine fold conveniently for stowage.

The machine with backstays in place.

Yours truly surveys the monster. Bwa ha ha ha!

The almost-finished machine. Note the knobs on top for adjusting the hingeline height at each end.

A business-end view of the machine. Not the router bit closely aligned with the hingline axis.

Up at Brads shop in Monroe WA, the mold for the winglet root ribs. The circles are where the 1-1/4" aluminum moment stub passes through the rib.

The root rib mold and the alignment fixtures for the moment stub and lift pins.

The fist-article root ribs.

The left side alignment fixture, with rib in place.

The left root rib fixed in place on the lower left winglet skin.

The whole winglet tooling set.

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page updated 9 October 2006 all text and graphics copyright (c) 2006 HP Aircraft, LLC