KitLog pro

Powered By Kitlog Pro v2.0

Jims RV-8
' style=
Date:  10-12-2013
Number of Hours:  2.50
Manual Reference:  7-7
Brief Description:  Tube flairing

Today I learned how to properly flair aluminum tubing. Again, this was something that I had a bit of anxiety about – fear of the unknown mostly. But, as has been the case – Get the right tool, do a little research on the internet and with some practice, I was able to make some really good flairs! Nothing too serious in the wings, but the tanks both have a vent line which brings in air as the fuel leaves the tank to go to the engine. There is also the option of putting in a fuel return line that some fuel injected engine require. That same fuel return line can also be used as a fuel purge to help with “hot starts” – by removing the hot fuel at the injectors and replacing it with colder fuel. More about that much later. Otherwise, I can easily seal the fitting. To get the idea, the air vent line goes all the way out to the end of the tank, (highest part of the tank). The fuel return line goes over to the 4th fuel bay and dumps the return fuel there. The idea is to get the fuel far enough away from the fuel pickup so that it can mix with other cooler fuel before it is sent back to the cylinders.

On with the building…so the proper way to flair a tube is on the following website.

http://www.gen-aircraft-hardware.com/images/pdf/GAHco_Flaring_Stainless_Tubing.pdf

I followed it with very good results. Even using the 5x glasses showed a good flair, no cracks or stress marks. The process is as follows :

1. Place the tubing in the base of the flair tool and using the back side of the flair tool (flat side) cut the tube with a 32 tooth/inch hack saw blade.

2. Using the debur tool, gently debur the inside of the tubing

3. Using a file, file the remaining tubing flush with the flair tool side.

4. Take the tubing out of the flair tool, and further debur the exterior edges with the file and then scotchbrite pad until nice and smooth.

5. Then, reinsert tubing in the flair tool and flair it.

That’s all there was to it, it took me about 4 practice flairs
' style=

start here

start here

' style=

all ready for final install

all ready for final install

' style=

return line terminating on left...vent line on top

return line terminating on left...vent line on top

' style=










Copyright © 2001-2024 Matronics. All Rights Reserved.