Wednesday, September 21, 2005

Bridi Utter Chaos



I test flew my new Bridi Utter Chaos today. I am reluctant to really call it an "Utter Chaos" because I made so many modifications to it. Here is what I changed:
1. I clipped one wing rib off of each side of the wing. My Killer Chaos' wing was just too long and this is basically the same wing. With the wing clipped, it is almost exactly the same as the Super Kaos. I had hoped for better roll rates and I was not disappointed!
2.The horizontal tail and elevator are a built up framework that should be covered with an iron on covering. Since I was going to fiberglasss the fuselage, I sheeted the horizontal tail with 1/16" balsa and used 3/8" balsa for the elevator halves.
3. I made the plane a tail dragger instead of using the tricycle gear arrangement.
4. The plans call for a fuel tank hatch on the top of the fuselage. I put the hatch on the bottom and put the canopy a little more to the front of the airplane.
5. I made the rudder about twice as big as the original and I made the leading edge of the rudder at a 90 degree angle to the plane where the original Utter Chaos' rudder slopes aft.
6. I used a single dowel to hold the front of the wings to the fuselage instead of two. I hope I don't live to regret this change!

I used Rustoleum paint over the fiberglass and used a DuPont clear coat but I found out that the clear coat is not fuel proof! The funny thing is though, I'm running FAI fuel with absolutely no nitro and it is still eating up the finish! I used Rustoleum Gold on my Super Kaos and the FAI fuel at it completely off. Another problem I have had with the Rustoleum is that it will not stick to the fiberglass or the primer. I actually used a different Rustoleum primer on this plane. On the Killer Chaos, I used a gray, sandable primer. On this modifed Utter Chaos, I used Rustoleum Auto Primer. It is black and quick drying. I am hoping the paint will stick better to it. On my Great Planes Super Skybolt, I tried using a Rustoleum latex primer so I could brush the first coat on to fill the low spots. The problem I found with this is that I can't wet sand the fuselage. The latex primer starts to ball up and come off.

The plane's paint job looks really good. One of my fellow pilots saw the plane today and thought it was an ARF and he thought the fuselage was covered with Monokote until he got closer and saw that it was painted. I hope the paint will stay put so I don't have to refinish it. I can build a Chaos in one day but it takes me several days to finish one.

Have any of you developed any good painting tips for fiberglassed airplanes? If you have, let's talk about it!

I used a Fox Eagle 4 .60 in the plane. I bought it used and it doesn't have the compression I would like to see. I may need to replace the piston and cylinder sleeve. In the meantime, I have replaced the .60 with my Fox Eagle .74. It is exactly the same engine except for a larger bore. The performance specs of the .60 and .74 are almost identical though! I was going to go back out to the modelport to try the .74 but we had a heck of a rainstorm move through the Salt Lake Valley this afternoon. I'll go back out in the morning and see how much more performance I get with the .74. I've run the engine on the test stand and it runs great.

I'll let you all know how it goes.

Jay Mc

1 comment:

Robert Forester said...

Ok so do you have the instructions for the modifications you made above to start to build an old utter chaos kit I have just acquired would be interested in the modifications you mad for better preformance.