Longeron bending!

[captain_john]

Forgive me, I know not what I do!

Here goes EVERYTHING! Yup, EVERYTHING! I have been holding onto these suckers for over a year and the time has come to SCREW THEM UP!!!



I got them rigged into the vise like so:



with the bitter end supported and am reading over the plans just to make sure of the sequence. The hacksaw is ready and I am willing!

I am also going to watch that video with the guy from Texas and the funny accent one more time just to hear him say "WARSHERS" again instead of "WASHAHS" like it SHOULD be pronounced!

Wish me well! Let's see if this Thanksgiving we truly DO have SOMETHING to be thankful for!

CJ

[cjensen]

CJ, if you can, or think about it, post as many pics as you can of this part. I'll need some reference in the future!

[captain_john]

I sure will!

CJ

[RV7Factory]

CJ, if you can, or think about it, post as many pics as you can of this part. I'll need some reference in the future!

Me too!

[Wicked Stick]

CJ,

Perhaps we can pick a night afterwork and get them done together.

Rob has done these on his 7A a while ago, so perhaps I can see if he's willing to stop by and assist.

[JohnR]

Yes, pictures would be good!

[jim_geo]

Good luck. I'd like to see those pix also.

[captain_john]

Yes to All!

Absolutely! This is one of those steps that is probably the most intimidating, but probably for no real reason at all.

Look at it this way, if ya screw up, ya just crate up some more. It is the crating/shipping charges that are the scariest!

WS, yes! I will be reading through the directions in the next few days. Trimming the ends and prepping the shop for the bend. I need to clear off the grinding table across the way from the door to make room for the ends to swing around. I think I have the space where the vise is located right now. If Rob would like to come over, that would be great! Have him order his harnesses while you are talking with him! He gave me a verbal, buuuuuuttt...

Pics to follow!

CJ

[captain_john]

Sooooo, before I got into the bending part of this, I figured it would be wise to get the "end cuts" done in case I screwed them up. Well, that was a good choice because I ended up cutting one off because I didn't like it! Put that one in your notebooks!

All I had to do was cut it off and slide it down a bit! Van gives you about 8 1/2" of excess material. This means you can screw up the ends once without ordering more stuff!







The Penn Reel box helps the camera to focus! Anywhoooo, the next thing to do is make the cuts for the F-711 bars. I drilled the end and then cut along the lines with a hacksaw. Once cut, I ran the drill up the center like a router.

I finished it off with the Dremel 3/16" router bit which was slightly oversize. Maybe 1/64" or so, but it really cleaned the edges up NICE!







Done deal!

Time to go to my health club and then to the EAA Chapter meeting! I am coordinating a Young Eagles thing this friday between my chapter and my school!

I will letcha know how that turns out!

Could be HUGE, Jerry! HUUUUGE!

What am I getting myself INTO!?!

CJ

[ptrotter]

CJ,

Your worrying about this way too much. I stressed over this and then it took me all of an hour to bend both my longerons. This is really not a big deal. I put them in the vise and couple of whacks with a rubber mallet and they were done.

[captain_john]

Yah Paul... I know I am.

It is all par for the course for me!



I am glad I began with the end cuts though!

CJ

[Wicked Stick]

CJ,

Your worrying about this way too much. I stressed over this and then it took me all of an hour to bend both my longerons. This is really not a big deal. I put them in the vise and couple of whacks with a rubber mallet and they were done.

Paul,
From what I hear the 7's are a bit more involved than the 8's to bend.
The 7's have an "arc" bend to them rather than a bend in 2 points and a single twist.

[captain_john]

UPDATE!!!

I am not sure that what I have done so far is the most precise method of construction. At first thought, I assumed that making the aft cuts and overall cuts and then bending would produce an accurate part. PROBABLY SO! Buuuuut, maybe now and I am not willing to do this all over if my little experiment fails.

Sooooo, I am going PER PLANS!

In the plans it says to cut them to length, bend them, fit them and THEN do the aft trimming.

Fortunately for me, there is plenty of excess material here to cut off the 7" or so of PERFECTLY SHAPED CUTS that I have already done!

Oh well, if I made perfect cuts once, I can do it again!

Besides, things always come out better the second time around!

Waaaaahhhh,

CJ

[captain_john]

OH, and Paul...

To add to Dave comment, we only need to bend 2 longs where the -8 had 4 of them.

Although these are slightly more complex, there are half as many.

Hmmmmmm, I should be able to do that!

CJ

[RVNewsletter]

there's a fair chance you'll end up doing some more trimming on the ends anyway. At least on the 7. This is a part that drove me nuts (the sound of longerons hitting the garage floor when thrown from across the garage is really cool!). But if there's a part you want to stay with and get it perfect, this is the one. The longerons are going to be a reference point for a couple of other important parts along the way....checking for level when attaching the wings (although you may want to go with the level on the 704 center section instead), for example.

When you go to add bulkheads to these things, the last bulkhead that fits the longeron -- the 712 -- is going to end up so the end of the angle that you cut is going to butt up against the bulkhead...and the longer prong is going to fit in the slot on the bulkhead and end up flush with the aft portion of the flange on the bulkhead. So you'll probably be doing just a bit more trimming to get it perfect.

The trick with longerons is just to do a little bit at a time instead of trying to twist and bend it all at once. Small steps.

You know what's cool about this phase, though? See how those longerons are all bendy and flexibile and kinda flimsy. In a few weeks, they're going to be the underpinning of a rock-solid airframe. It's cool how all these flimsy things fit together and get strength from each other.

[captain_john]

Thanks Bob!

I am also thinking that I need to cut off these nice cuts that I already made for another reason as well. Sliding them through the bulkheads will be hindered as well.

I sure am glad I have the extra length I need!

I will let ya know how I proceed!

CJ

[RVNewsletter]

No, you won't need to do that. You don't actually need to slide them through. You actually tilt the longeron inboard slip it into the slot on the bulkhead and then twist it back outboard. It's pretty simple. Might not hurt to have a second pair of hands but it's not really necessary.

This will be no factor at all as you assemble.

[JohnR]

So you got these bent yet CJ or are you still eating turkey?

I'm about there myself. Maybe this weekend sometime.

[captain_john]

BOTH!

Turkey was DAM GOOD! I had TWO MEALS TODAY!!!

Anywhoooo, here is the jiggy thing Wicked Stick came up with:



He IS a WIZARD!

He was going off on some tangient, but I reeled him back in and I think this ended up being a reasonable comprimise between his (I am sure AWESOME but over my head idea) and what I saw as feasible.



It worked VERY WELL, as it concentrated the bending force in one, rounded location!



The hammers sat idly by and all the bending was done by the weight of our bodies.

Here I am coaxing the sharp downward bend with a hunk of PVC as a "cheater".



Once they were bent and checked for accuracy, the side rails were drilled to the longs and they were hung up for storage.



Now I have configured the "JIG area" for the fuselage!



Here we go again!

CJ

[cjensen]

That looks like it worked well CJ! What kind of radius did you use on those boards?