S

Skyhawk

Member
Hi!
Motivation is back and I?m curently working with the VS. ;)

I come to an halt when working with the spar doubler. Those optional lightening holes gets me a bit pensive. Why is it optional?? What to loose/gain whith or w/o those holes?
Gain some (little) weight, of course :), but I would appreciate your thoughts about this...
I feel more comfortable with options like color and equippment then those structural ones, but its a long time to that phase... :rolleyes:

Thanks
 
Loose the weight, drill em out

Everything you can do now to loose a little bit of weight is good, especially in that area. You can compensate it later by installing goodies or nice interiors!
 
I'm told the newer kits are shipped with the lightening holes already added to the doubler. It is the builder's option to add such holes in the earlier kits. Here is an older link that describes my experience and the weight savings noted by adding the optional lightening holes:

http://www.vansairforce.com/community/showthread.php?t=2445&highlight=lightening+holes

That said, many builders assert the -8 is inherently nose heavy and a little extra weight back there can't hurt a thing. YMMV.
 
My 9A empennage shipped in December of 2007, and it had the optional lightening holes already cut. The plans still showed them to be uncut and optional, but the metal had been cut.
 
I cut them out

Same option was stated for the -7 HS, the holes are optional.

I bought a fly cutter (I think from Avery), and looked at some posts on the topic hereabouts. Most of the advice was to use a slow RPM on the drill press, take your time, and support the work well.

Did that, and the part came out great. Then, holding the cut-out pieces in one hand, I realized that I was saving some significant weight.
 
Just DOOOOooo eit.

Seriously though, there is NO structural reason not to, just that it's more work.
 
lightning holes

I had the option to cut the holes and I did not. I keep hearing that it should have been done but I believe the W & B of the -9 will allow me this little indescretion, time will tell, have no idea about the -8/A.
 
Probably a silly question!
Do the now pre cut lightening holes that come in the more recent kits need to be deburred?
John
 
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