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Guy on the Biplane Forum reports that Wicks says they can't fill his order for a set of spruce spars due to the difficulty of finding spar stock of sufficient quality.
The wording of the actual message implies they are no longer going to carry spruce at all.
Ron Wanttaja
Given the lead time I saw from Aircraft Spruce on my capstrip order, I had already pretty much decided to start looking for an alternative wood for my spars, and maybe longerons as well. Douglas fir or western hemlock are two candidates.
I'm not familiar with that forum. But have they considered using aluminum spars?Quote:
Originally Posted by rwanttaja
http://www.carlsonaircraft.com/spar.html
--Bob K.
If you want to stick with wood spars I would seriously consider some of the engineered wood products in use in the construction industry. It would't be that hard of a calculation to find an engineered beam with the same strength as any given size piece of spruce, and it would probably be smaller than the spruce piece, and possibly lighter.
The original poster is building a Marquart Charger, and I don't know the situation there.Quote:
Originally Posted by BoKu
But we've been talking about this for a while in the Fly Baby community. Many builders are already going with Douglas Fir, which is an acceptable (albeit slightly more heavy) alternative. There have been discussions about laminated spars, too.
Me and another man have discussed omitting an evolutionary step entire, and going to an all-metal wing. There's precedent, in that a Luscombe-winged Fly Baby flew about 40 years ago. We have discussed using a built-up aluminum spar, using the RV or Zenith series (or the Carlson!) as a starting point. If one covers the bottom of the wing with aluminum, riveted to the bottom of the ribs, that would probably greatly reinforce (if not flatly eliminating) for the normal internal cross-wire bracing. I'm holding out for the standard semi-elliptical wing shape, but that would be hard to do with a simple metal wing.
We'd probably build a test wing first. The problem is, it would be better if a structural engineer looked at the design first and gave his or her blessing. Hard to arrange. The beer-soaked napkin holding the original Fly Baby calculations probably ended up in a landfill 55 years ago. Back then, building a small wooden airplane didn't take too much computational effort.
Ron Wanttaja
As a Tech Counselor in Composites & FWF, I would try to stay with in known Aviation specs / what other aircraft have done even if its not the same exact type of aircraft.
these links may help:
https://www.eaa.org/en/eaa/aviation-...th-wood-part-1
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&u act=8&ved=0ahUKEwiJ6PrVqPLXAhVHWSYKHeMDCScQFggpMAA &url=https%3A%2F%2Fwww.faa.gov%2Fregulations_polic ies%2Fhandbooks_manuals%2Faircraft%2Famt_airframe_ handbook%2Fmedia%2Fama_Ch06.pdf&usg=AOvVaw1whAoRCO yEQoG4cXiqTT6M
Hope this helps,
Spencer Gould
Has anybody inquired with Wicks to see if they are conserving spruce for the build kits and just not filling erroneous orders?
Jim
One of the Fly Baby crew stopped by the Aircraft Spruce offices in Georgia this week. He reports that spar stock greater than 16 foot long, 6" wide is difficult to find, but they can fill orders for smaller pieces easily. Fly Babies use a 3/4" thick, 6" wide, 13-foot front spar, he said they had enough in stock for a half-dozen Fly Babies. The ACS rep also noted that, beyond occasional spot shortages, they anticipate no problems finding spar stock in the future.
Other than the usual worries about pricing due to lack of competition, it sounds like production of the traditional homebuilts shouldn't be affected.
Ron "All Hail Our Sitchensisian Overlords" Wanttaja