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Old 08-24-2009, 03:38 PM
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swisseagle swisseagle is offline
Join Date: Feb 2005
Location: 20km outside of Zurich, Switzerland
Posts: 522
Exclamation Be very carefull!

Hello Chris and others

There where lost a few RV's because of bad flarings within the first few hours of flying! In switzerland we lost the first RV-9 due to that! Be very carefull here.

It is a shame how the supplyer of the flaring tool describe how to use it. Also Vans should write a page about how to do it right!

In an accident report they refere to Norm SAEJ533 below I copy in that what I found on different sources. Resurch for yoursefl or ask your tecnical conselor!

Also is the material 3XXX not so strong, a "thinned out" flare will crack and separate from the tube under stress (due to not propperly adjusted, bended, under vibration, and so on, tube). 5052 is stronger but more expensive, especially to send around, they get sended straight and not coild.

Also when you tighten it the first time, let the material "settle" down, open the connection and tighten again. There is also a table with values for the tourque that is needet to tighten a nut or you can count the flares. Here is a link to Vans page with original information:

I hope it helps, and I hope also a person who is in the "flare" bussines join in and give his comment and advices.

Regards, Dominik

· Ensure that the end of the tube is cut square within ±1 degree and remove the burrs and sharp edges.
· Wipe the ID and the OD of the deburred Tube end properly.
· Insert the nut and sleeve on to the tube as shown below

Flare the Tube with a special flaring tool to 37 degree, dimensions of Flared Tube according to SAEJ533 standard as shown below.

Screw the nut on the body until finger tight. Further tighten the nut with a wrench ¼'' turn in order to make a leakproof metal to metal sealing connection.

Dimensions are for reference only, and are subject to change without notice.

Last edited by swisseagle : 08-24-2009 at 04:24 PM. Reason: added more information
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