Doug and Brad were in the shop from 18 to 24 February making a pair of all-carbon wing spars for Brad's wings, and also making a set of outboard drag spars. The weather started off pretty iffy, and we came close to cancelling ADF8 because if there was a storm in the Sierra it would be hard for Doug to get in from Reno. However, the weather cleared up and the guys made it over the pass just fine and got right to work. The first batch of their photos are below, and there are a few more that I took with my daughter's camera that I haven't yet downloaded.
On 21 February, Brigitta waxes poetic on the spar mold. The guys had spent the previous couple of days cutting about a quarter mile of pultruded strip for the spar caps.
Doug and Brad cut foam for the spar shear webs.
A few of the pultruded strips for the spar caps. The guys used short sections of spiral wrap to organize the strips, which I thought was a neat trick. If you do that, cut the ends of the spirals blunt so that they don't tear your elastic gloves.
This is huge roll of Hexcell 12oz carbon cloth that I got at a great price through the salvage market. It had quite literally fallen off of a truck and the shipper's insurance company wrote it off. John Higgins saw it listed on Craigslist and alerted me, and I went and bought it. Thanks again, John!
Here I'm working on the vacuum plumbing for the spar mold. The long whitish strip down the edge of the spar mold is 1/2" ID spiral wrap like you'd use for wiring harnesses. We buy it by the 100-foot spool and use the same pieces again and again.
Doug prepares to cut bias carbon strips for the spar shear webs.
Early evening 22 February, we have the first spar laid up and bagged down. We had almost run out of pucky tape, so we sealed the bag onto the mold with a few strategic strips and darts of pucky tape, and the straight runs with plain old duct tape. It worked okay.
The convoluted topology where the short C-section ends.
Here I do a bit of pipeline patrol and seal a minor leak.
Early on 22 February, Doug and I clean the pultruded strips with acetone. This step probably isn't strictly necessary if you handle the strips only with gloved hands and keep them in a sealed carton as we have not done.
Mid-afternoon, one of America's foremost sailplane development teams rests after laying up and bagging a second wing spar. From the left, that's Doug Gray, Brigitta Kuykendall, Bob Kuykendall, and Brad Hill.
On 23 February, Doug cleans up the spar mold after the second spar layup.
Here's the four wing spar parts, two short C sections, and two long ones.
That afternoon, the guys laid up and bagged the first of two outboard drag spar parts.
They also bonded together one each of the short and long C sections to make an I-beam wing spar. I think that's every clamp that we have in the shop.
On 24 February, Brad shows off our first all-carbon wing spar.
Later that day the guys laid up and bagged the second outboard drag spar and also bonded together the remaining C-sections to form the second I-beam spar. Then they packed up and headed home.
Homebuilt aviation is not for folks who don't try things at home.
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page updated 26 February 2009 all text and graphics copyright (c) 2009 HP Aircraft,
page updated 26 February 2009 all text and graphics copyright (c) 2009 HP Aircraft, LLC