Comment

Comment by Gary Lee Weber on February 6, 2012 at 12:22pm

Jesse,

There's more than one way to skin a cat.(or rudder in this case)  Here is what I did.  I took a piece of heavy non- corrugated cardboard and laid out the right side rivet lines and spacing on it.  I drilled holes through the cardboard and used this pattern/templet to make sure everything lined up on the rib and spar centerlines.  Once everything looked good I laid this on my rudder blank and drilled right through the holes into the blank and table. if you drill into your table you can put a few clecos in to hold everything lined up.  once the right side was done I flipped the templet and did the left.  I then bent the blank on the center line.  

In hindsight it would have been better to bend the blank and drill both sides at the same time.

Mistakes are inevitable.  Made three #2 and  two #1 ribs before I was happy with them.

Also, good Idea from Phil to leave the trailing edge holes until later.

Have fun and remember you can always make small parts from botched up larger ones.

Comment by Joe Harrington on February 5, 2012 at 10:36pm

Phil has it correct. The trick is to get shared holes all in the correct location. By this, I mean the hole in rear skin, the leading edge skin, and the rudder spar will all share the same rivet. You have to think ahead where everything will be. Once you yet the hang of it, the methodology is the same all the way through the project. You WILL make some mistakes, especially early on. Don't sweat it. Many mistakes can be fixed or compensated for and the ones that can't, then simply remake the part. All part of scratch building...

Also to add to Phil's procedure, draw a centerline down the rib flanges which you will line up through the rivet line holes in the skin. This is how you correctly position the rib inside the skin for drilling. Hope this makes sense..

Good Luck!

Joe

Comment by Phill Barnes on February 5, 2012 at 7:10pm

Hi

If you lay out your rivet lines on one side of the skin, using a pitch guage and a 3/32" bit, drill right through both layers of metal. When you get to the trailing edge holes, it may be worth leaving these till later to check where they fall on the rib to make sure there is enough distance between the flanges of the rib to accomodate the rivet bodies back to back. Alternatively, stagger the the these holes by 5-10mm. Be sure to use gentle pressure when drilling through the skins particulary if you have a soft surface undneath like cardboard. As long as you have positioned the ribs in their exact location in reference to the plans and use the same measurements and rib angles on the skins, then all will be well. Happy building.

 

Phill

Comment by Jesse Hartman on February 5, 2012 at 7:07pm

im building a ch 750 from plans. the manual is set up for kit builders.

Comment by Marvin W Miller on February 5, 2012 at 4:31pm

Are You building a Zodiac 650? If so and You have Your rudder frame clecoed together. Next step, disassemble, deburr, and rivit it together. I am assuming You have the rudder kit. You just have to read and study the manual You got with it. follow their steps and You will come out with a good rudder.