Eagler's Nest

Airframes => Single Seaters => Topic started by: fresnoxl on October 14, 2023, 08:57:59 PM

Title: wing spars
Post by: fresnoxl on October 14, 2023, 08:57:59 PM

I'll be starting the spars on my XL soon and the plans call for tapering the spar cap down to 1/4 inch 34 inches on the end of the wing. My question is why? Thanks

Title: Re: wing spars
Post by: Dan_ on October 14, 2023, 09:20:57 PM

It saves weight and lift is less out to the end of the wing, so less stress on the spar...
:emoji_u1f62f:

Title: Re: wing spars
Post by: fresnoxl on October 14, 2023, 10:42:55 PM

Thanks, I wondered if that was the reason. I wonder how many ounces it saves? I have to drive from Fresno to Carona CA, just to get the spruce cap strips at Aircraft Spruce. I'll also pick up some 4130 and plywood. 530 mile round trip makes me hesitate at cutting on the cap strips.

Title: Re: wing spars
Post by: Dan_ on October 16, 2023, 12:58:59 PM

Measure 3 times, cut once...

Title: Re: wing spars
Post by: Dan_ on October 16, 2023, 01:01:12 PM

Measure, write it down.  Measure again, write it down.  Measure one more time, and cut...

Title: Re: wing spars
Post by: Shay King on October 24, 2023, 09:43:53 AM

I don’t have my plans to hand at the moment, but I think there was an amendment. The taper may be to 1/2” now instead of 1/4”.

Title: Re: wing spars
Post by: Kamcoman77 on October 24, 2023, 12:40:29 PM

My XL plans (H-51) still say 1/4" at the end, but I just couldn't cut my spar caps that thin. I tapered mine to 1/2" tall starting at 34" from the tip.