Rudder skin edge break mistake
 

Despite practicing on some scrap metal I still made a mistake while putting the edge break on the rudder skins. I was using the vice grip edge forming tool and while I was pulling it along the edge the skin moved outside of the flange on the roller and I bent the skin way too far. And to make it even worse I did the same thing again a little farther along the edge. I did my best using my hand seamer to straighten the edge out and clean it up but there was only so much I could do.

Since the trailing edge is so important on control surfaces I'm wondering if this will be a bigger problem than a cosmetic issue and if anyone has any suggestions on how to smooth the skin out a little better.

Here is a picture from right after I made the first mistake


And here are some pictures from after I tried to fix it

Hey Tim -
One thing you could try is to cleco it together to see if the edges come together. My guess is that it's not as bad as you think.

Additionally, take some pressure off the pliers - you don't need them so tight as you pull to make the edge break. IF you're pulling that hard, it makes it difficult for the rollers to turn and then they can wander.

When I was first starting, I had the mindset similar to dimpling where there is not an overpressure situation. In this case, too much pressure doesn't hurt the material but can affect your ability to keep things straight and smooth.

Try it on some scrap. YMMV

I actually did cleco it together but don't have any pictures. The edges do come together fairly well with just some very small gaps. I think the waves in the skin at the edge are what's bugging me the most. Of course it may not be too visible to anyone else who doesn't know it's there but to me I feel like it will be the only thing I see when I look at the rudder.

I think you're right about too much pressure on the pliers. I just didn't feel like it was doing anything before I tightened them up, so maybe there was some middle ground that I went right past.

rudder TE
 

I did something similar. My mistake was going over the trailing edge twice with the edge forming tool. In a couple spots the big part of the roller that rides along the edge of the sheet metal got slightly separated from making contact. Result was the metal got double-bent. It didn't give double the angle but it was still pretty similar to what I see in your pic.

I didn't even try a hand-seamer, just pressed it hard against the table surface to get it mostly smoothed out. Once i prosealed it and cleco'd to my chunk of angle steel, the boo-boo was invisible.

This video might be helpful to properly adjust the tool.

https://www.youtube.com/watch?v=DbAEuFbFaco

Tim,

When you final rivet it together, you'll use Proseal in between the skin and the AEX wedge. When you do this step, you could always apply some clamps in between the rivet holes (if needed) to help bring it all together. I used a steel angle, with the clecos going through it, to bring it all together nicely and, more importantly, keep it straight until the proseal began to cure. Then I riveted it together per Vans instructions. I think yours will come together fine. Besides, have you looked lately at the trailing edges of the POS Cessnas you rent!? :p

I definitely had a learning curve with this tool, and the Cleaveland video link is a good vid. I use very little clamping pressure on the tool (really just enough to where it won't fall off the sheet). Hard to describe, but I don't really pull the tool. I steady it using the handle and with my other and I kind of rotate the top roller. This gives much more control and prevents the type of excursions you had. Some people curse this tool, but I really like it now that I've found a technique that works. Lastly, the 'bend' is almost imperceptible to the naked eye. You can barely tell the edge is broken, however it is enough to prevent the edge from drawing upward when riveted.

The sad part is that I actually watched that video first and I still set the pliers too tight. I still think it's a good tool though. I'll just be more careful next time I need it.

I'll probably try to flatten the skin out on my workbench but since I've dimpled it already I imagine there's no hope for it being any better than it is.

I was actually planning on giving the tape a try for the trailing edge instead of the ProSeal, and I have ordered the tape already, but I'm sure the ProSeal will create a much stronger bond and might hold the edges together better so I'm second guessing that decision.

Technique
 

After a couple botched breaks and lots of curse words, I found this technique works perfect. I also roll the rollers with a finger. Better control.

Two-handed method
 

I found the safest way to use this tool is to use two hands. Much better control. I made a small nob to screw on to the exposed 2 or 3 threads on the end of the top bolt. Clamp the sheet down to the bench with a few inches overhanging. Make 2 to 3 passes along the edge tightening the tool after each pass rather than trying to get the chamfer in one pass.

Stewart Willoughby, 6 panel/wiring