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Backup fuselage longeron

Lefty37

Member
Should I order an extra just-in-case longeron for the fuselage with my wing kit? Or is bending the longeron an easier task than imagined.
 
Extra longeron

Should I order an extra just-in-case longeron for the fuselage with my wing kit? Or is bending the longeron an easier task than imagined.

Yes and yes. It's not difficult but make a mistake and a replacement will cost more to ship than the item price.
 
errors

I don't think bending the longeron is a big deal. It was very nerve racking because I had never done it and everyone said it was a big deal, but like many other parts of the build, the fear is worse than the bite. I think if you just take your time, think things thru and be careful, the bending is not such a big deal. After having gone thru this, and seeing where others have had problems, the biggest issue seems to be drilling holes in the wrong spot later in the build. JMHO.
 
I agree with John. It?s not the bending but the drilling. I blew the edge distance near the tail. Having 1 extra would have been pointless. Just be careful and measure twice, three or four times before drilling. Buy a set of the Buller bending dies and that will be easier too.
 
There are two parts to the longeron bend. The side curvature and the downward bend. The side curvature is relatively easy and you get a full size drawing template. I transferred the drawing shape to an aluminum template by punching witness marks through the paper to the aluminum. I used a small bottle jack in a homemade press to bend the side curvature. I did both at once, clamping the longerons back to back and using a hardwood shoe with a slot in the middle on the jack to make the bend. A little patience goes a long way here.

The downward bend that conforms to the side skins I found much more difficult. I had the longerons mounted in the fuselage and ready to drill when a co-builder pointed out the downward bend wasn't sharp enough. So I removed the longerons and made another aluminum template based on the shape of the side skins. Vans instructions say to make this bend with a dead blow hammer which is what I did, but there was a LOT of hammering required to get to the shape I needed.

The answer to your question is: Go ahead and order a spare set of longerons, but don't be surprised if you don't need them. As you observed, the cost of shipping just the longerons exceeds their cost. And they are not likely to be able to be sourced locally.
 
Check first to see if there's a supplier of metal near you that carries the sizes used in the longeron in the same alloy, probably 6061-T6. If there is, then you can buy a replacement locally if needed. But often they won't carry the size.

The longerons are long and thin and light. It's easy to carry tied to a car or poking out a window, but easy to scratch, too. If you need to go get one, consider bringing along something to protect it with.

If for any reason you can't easily get one locally, then do consider ordering an extra.

Dave
 
I did on my 7 fuselage order just a month ago... figured I could use the angle for something else if I didn't need. Cheaper now than later.
 
Keep in mind that bending trouble isn?t the only mistake you can make on the longerons. If you drill them incorrectly, you?ll have to re-do them too. See this thread for example. If I were to go back in time I would have ordered two extra longerons with my wing kit, just to be sure.
 
Simple or not Ryan and I both messed up a longeron. I would order an extra. You'll use the angle lots of places if you don't mess them up so I don't see the down side. Sure you can buy from your local supplier but its a lot easier to have your own stock.
 
Them things are so cheap it didn't make sense to me to not include two extras in the wing order. As Dave said above, you can get it from a local metal supplier but if you live in the boonies like myself that isn't an option. Plus I figure if I don't need em I will make some kickin cool fuel storage tank for transport or something.
 
Check first to see if there's a supplier of metal near you that carries the sizes used in the longeron in the same alloy, probably 6061-T6. If there is, then you can buy a replacement locally if needed. But often they won't carry the size.

The longerons are long and thin and light. It's easy to carry tied to a car or poking out a window, but easy to scratch, too. If you need to go get one, consider bringing along something to protect it with.

If for any reason you can't easily get one locally, then do consider ordering an extra.

Dave

This may bear repeating...if you source locally, make sure it's *structural* aluminum angle extrusion (radiused on the inner angle).
 
I took the advice given to me and purchased 2 extra longerons with my wing kit. For around $20 per piece, it seems silly not to do it. I'm a long way from doing the bends but happy to know the reserve pair is there if I need them.
 
I?d order a length anyway for savings in shipping. Apart from mistakes I?ve found it useful for other things such as supporting the radio stack and bracketed here and there. I was lucky in that vans sent my buddy a bundle for free
 
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