Weight Savings From Creating Lightening holes on the V-S Spar Stiff.

[briand]

Anyone ever weigh their plugs after drilling them in their VS808PP?

[AX-O]

I was wondering the same thing. Is it worth doing?

[ge9a]

I didn't weigh mine, but it didn't seem very significant at the time. The small things may not seem worth the effort, but I have taken the position that I'm going to take advantage of all of the 'recommended' weight-saving measures that are in the plans, and I have so far (unless I've missed one or two). I figure all of the little things will all add up to something a little more significant. And almost everyone I have talked to with RV experience says "built it light" and "build it per the plans." So I am. And then I won't feel as guilty when I add something to the panel that I'd like to have there.

Just my 2 cents' worth.

[AntiGravity]

I cannot believe someone would be sad enough to care. Oh wait, no I was!
I weighed the VS before I started, and then weighed it again when I was doen. Total saving a whopping 95g! Still, if you can save small amounts in many places you can overall save a large amount. All helps. Of course, I probably added this back in primer but what the heck, a saving is still a saving, right

[Jekyll]

95 grams translates to .209 pounds. Not much weight however, it may be noticeable on the CG as it has a large arm.

People talk of building light and many often consider that to mean removing mass from the design wherever possible. Well, after going through all major components, I've come to the conclusion that this view is marginally misguided. If you avail yourself of all the areas where Vans highlights the option of trimming material for weight reduction, you may save 1.5 pounds, possibly 2. Don't eat that burger on your Saturday flight or you will put that back on. If you start trimming areas not identified by the engineers, then you are assuming responsibility for structural integrity in a manner you may not be qualified for.

Building light means watching what you add to the airframe, not looking for meaningless extra mass to trim. Heavy primer (excess) will add more weight than you can possibly trim away. 3 coats of color followed by 3 layers of clear coat may look very nice but, that's a lot of weight (not to mention a significant aft CG shift). Prop and engine choice - big impact. Panel decisions? See where this is going?

For me, the biggest target for weight reduction is my waistline. I can trim away 80 pounds of excess material without compromising the airframe.

Jekyll

[jcoloccia]

It really does come down to WHERE you're trimming the weight. Especially on a -7, anything you can do to get that CG forward is going to help. If I were building an -8, I'd probably not cut them out.

The way I did mine, I cut them out a little smaller than called for in the plans. This just made the measuring easier (i.e. you can be a little sloppy and not sweat it too much....sloppy in my case was I got it in the right position, centered to within about 1/32...I could do better, but no need).

All in all, they added about 1 1/2 hours to the build time for me, including deburing and stuff.

[Rick6a]

Originally Posted by briand

Anyone ever weigh their plugs after drilling them in their VS808PP?

Yep, check out this thread for my before and after weight observation.
http://www.vansairforce.com/communit...ead.php?t=2445
Rick Galati RV-6A "Darla"
RV-8A empennage done

[N941WR]

Originally Posted by Vans

Build lightness in!

As you build there will be a number of places that Van's tells to you trim something just to make it lighter. Your call. Me, I'm doing everything I can to make mine as light as possible.

[Jekyll]

My earlier post sounded like I don't remove material where recommended. To the contrary, I do act on those recommnedations when possible. I just don't anticipate much net reduction and realize that my ultimate weight control is in watching what I add. I've got a QB so some of those parts with optional trimming have already been assembled and the factory didn't always do the trim. I am pleased that they made some of the trims. I'm not interested in dissassembling the QB to do those optional trims they passed on.

Back to the waistline issue....... My flight surgeon seconds my weight reduction concept.

Jekyll

[AntiGravity]

Jekyll, this is very true. Not flying yet, but skydiving and I've always been a fast faller. As a jumpmaster it just doesn't look good when gravity takes priority and you leave a student floundering on their own in mid-air . Losing 10kg has helped enormously! I sometimes wonder how my wife and I will fair when we get the -8A built, from a CG perspective. We're only 70kg and 54kg; I guess we'll cross that bridge when we get there! Meanwhile though, I'll save weight where I can, so longer as structural integrity and safety are not compromised...
Blue Skies!!