Originally Posted by
nixrox
Hi: I am an aircraft mechanic and certified Non Destructive Testing Specialist (x-ray weld Inspector) with 40 years of experience. I don't usually comment on forums like this, unless I see a problem that is personal safety related. In the case outlined here 'welding an aircraft engine mount' - unless you are a certified AIRCRAFT welding specialist (either AWS or CWB), you should not be welding any LIFE CRITICAL components. You could be risking not only your life, but any passengers, or innocent bystanders on the ground, when you fall out of the sky. If you intend to continue with this folly, at least go out and buy the best Ballistic Recovery Parachute you can find, plus no passengers and no flying over populated areas.
Every certified aircraft engine mount was designed by an aeronautical engineer, a welding engineer, as well as a level 3 welding inspector. Each has a specific area of expertise. It starts with the computer design and testing of the mount and they will use stress analysis to make sure there are no weak spots in their design. Then a welding jig will be designed and built by the welding engineer and level 3 weld inspector, as well as the weld procedures, which a certified aircraft welder will follow to the letter. The procedure outlines the specific filler rod, the amperage settings, the speed and angle of the welding process etc etc etc. It follows with dozens of trial and error tests to make sure the welds will hold in the most impossible situations you can imagine. All this preparation before they even begin to weld the mount.
Welding is never as easy as it looks, especially on LIFE CRITICAL components. My recommendation - find a certified aircraft welder, who has extensive hands-on experience with this exact type of welding, as well as an approved weld procedure and welding jig. It does not matter how much it costs, if the end result is you do not kill yourself or others. OR the BRS is your last resort. I worked for two years in a helicopter search & rescue squadron - I carried more than my fair share of body bags.