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Bending Servo Trim Tab Ribs:: Blog Excerpt


Radial Skybolt Builder: 220.45% completed
Supporting Member
Aug 21, 2006
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South Jersey
The multitude of things you need to do after you thought you were just about ready to do it. And the time that it take to complete the task at hand is squared by the desire to get 'er done.

It's not that I didn't realize that I had these tasks to do before I started putting together the pieces for the tail feathers... it's the fact that there are sooooooooooo many tasks. I believe that bending the metal ribs for the servo trim tabs are the last task before moving on to the "big" project, the actual putting together of the tail feathers.

Thought real hard all last week of just calling up Steen Aero to see if they'd sell me just the four metal ribs for these servo trim tabs. Decided that since I had these pieces already cut and partially bent I'd give it a try. More than give it a try... I was going to make them.

Set my table saw up to cut the shape of the metal rib with angles of 60 degrees and 30 degrees. No hardwood sitting around so I picked up a piece of partical board. (Pretty damn hard compared to a pine 2x4.) Turn the saw on and made sure my fingers weren't in the way of the blade as I cut the thin strip of wood that was going to be my template/bending block.


<DIV align=center>The "bending block."

I used the vinyl flooring as my table as I began to bang away on the metal rib with a dead blow hammer. I was suprised at how fast this was taking shape. A little tweak here and a little tweak there and I'll be done in no time. And I thought that this was going to be a long night with not a lot accomplished.


<DIV align=center>The first few bends I had made on a bending brake.

After about ten minutes of sculpting this masterpiece I was "close" to being finished. Laid it up on the table to see what a nice job I had done and was surprised at what was once a flat metal rib now turned bowl shape. Actually, I wasn't surprise... nothing surprises me. I thought about it and banging the heck out of it like I did was no different than taking this thing to an English Wheel. I had always thought that that piece of tooling look primal... something out of theMedieval Times. What I was doing was taking this concept back to the Stone Ages. (I only wished I had started doing this stuff, er continued doing this stuff back when I was younger. I'd be pretty good with the English Wheel by now. I digress....)


<DIV align=center>Shot of the rib against a aluminum bar to show bend.

The trick now was to finess it back into being straight. I set about to bang it some more... bend it a lot... finess it a little... I wasn't getting there as fast as I wanted or as fast as I thought that I should. Thought about making the call to Steen Aero tomorrow to place that order for these four ribs. Thought about it a few times. Then thought.. the hell if I'm going to give in when the learning is getting a little tough... the hell if I'm going to lay down and give up. So I continued doing what I was doing and learning a little of the art that I was to learn.

And learn, I did. Twenty mintuesof bangingtwo metal ribs close to the shape they needed to be... another two hours and twenty mintues of learning; of banging and squeezing to put the finishing touches on them.


<DIV align=center>Finished product. One of four servo trim tab ribs.
<DIV align=left>

I liked the outcome of the last three hours. Another three and I'll be ready to make those tailfeather... Edited by: Jerry

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