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View Full Version : Is this spruce spar stock OK?



drigotti
06-02-2015, 06:11 AM
Folks,
I have obtained some spruce for a possible project from a long time chapter member. 2 pcs have a "feature" that I'm not sure of. The "main spar" piece has a joggle in the grain @ 65" from one end. It shows up @ 9" closer to the end on the other face. The "rear spar" has the "feature" only showing on one face and does not show thru to the opposite face. I'm told this is OK per MIL-S-6073.
Take a look at the attached pictures and let me know what you all think? Is there someone at EAA that I can discuss this with?

4846
4847

Thank You

Dave Rigotti

planecrazzzy
06-02-2015, 06:37 AM
I'm with you.... Your "Gut" is telling you this is NOT up to a good Spar Standard...

If Aircraft Spruce sent that to me... They'd be sending me replacements...

In fact... They sent me a replacement because one spar weighed 5 lbs more than the other...

To me.... Looks like good material to CUT-UP for cap strip material.....

I'd spend the $200 on new Spars....Peace of Mind.... Priceless
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Gotta Fly...
JAM
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martymayes
06-03-2015, 06:54 AM
Wavy grain is acceptable provided the limits are not exceeded. As you have already noted, sometimes necessary to evaluate all four sides of the board. Can't tell from the pic if it's acceptable or not and even if it is acceptable, whether of not I used it would probably depend on where the defect was located in the final product. I wouldn't get to excited about wood that barely meets minimum acceptable requirements, especially if the defect falls in the most critical section of a wing spar. Yea, it's acceptable but is that really what I want?

Richard Warner
06-04-2015, 05:44 PM
Dave, if it was me, I wouldn't use it. Why worry about something for the time you own the airplane when a couple of hundred dollars would take that worry away. I wonder what the top & bottom of the spar looks like?

drigotti
06-04-2015, 07:20 PM
Folks,
Thank You for the replies. "If in doubt...throw it out!" Will probably make some nice longeron stock........

Dave Rigotti