Simple fluting question

[markpsmith]

I just started my RV-8 tail kit. I understand what fluting is now, however, if the rib is not bowed and the pre-punched holes line up - do I need to flute?

I am confused of all the fluting talk since all of my empenage ribs are all pretty much flat from the factory...Is this normal or am I missing something here?

Thanks,
Mark

[Paul Eastham]

As long as the holes match up with the skin or other parts, I wouldn't touch it. You may find parts that appear flat but need fluting anyway for hole alignment.

Paul

[briand]

The rounded tipped ribs are the ones that usually require fluting. All of the H-S and V-S ribs needed fluting in my -8 kit.

[Tom Maxwell]

Perhaps you are just not looking at them critically enough. I thought the same thing when I started my tail kit but a more experienced builder pointed out to me that what I thought was perfectly flat was not.

The laws of physics tell us that if we take a flat piece of aluminum and smash it into a three-dimensional object, there will be forces on the object that tends to distort it. Any formed piece of aluminum in your kit will likely need some fluting.

The key to learning to see this it to assure you have a perfectly flat surface upon which you can lay these pieces. A wooden bench top is not optimal. I built my tail at the Alexander Technical Institute and they have a large piece of 3/8 inch steel plate set into a table top. My instructor laid each rib on the plate and pointed out where and why it needed to be fluted or where I might have over fluted. A piece of 1/4 inch class such as a glass cutting board or your wife's glass table top will work well also. Well, maybe not.

I think the key is learning to see the issues you are trying to correct. This isn't necessarily as intuitive as one might think. It isn't difficult once you learn what to look for, but to the neophyte eye, it can be difficult to see and getting an experienced person to point it out to you is usually all that it takes.

Good luck!

[cytoxin]

are not on a radius as in a wing rib you may not need to flute. if it were square there is not much if any fluting required. if clecoes will very easily go in all the holes then fluting may cause a misalignment. clecoe the end holes and at rest if all the holes align then let it ride..

[gpiney]

The real key is to get the holes to line up. Always square the flanges first before fluting. Check out this thread to read about what I discovered about fluting the empenage.

http://www.vansairforce.com/communit...hlight=fluting