MY-14's tail repairs, part two

Sunnuntai 25.9.2016 - Reino Myllymäki


Tuesday Club’s Matti Patteri made an assembly jig for joining of MY-14 fuselage and MY-9 empennage. Joining was done at Finnish Air Force Museum in Tikkakoski. Damaged tubes were straightened and cut where necessary. New pipes were taken from MY-9 fuselage as needed.

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Assembly and straightening was made as close to drawings as possible. Pipes were bended with the help of welding torch to align them exactly right. Also supporting wedges made of laminated wood were helpful during alignment.

Tube to tube joints were strengthened with sleeves. Corner joints where tube endings were shaped remained without extra support, unless there were original support flanges.

Myrsky’s fuselage is a welded frame made of chrome-molybdenum alloy steel tubes. Welding method was gas welding with unalloyed wire. By the time when Myrsky series was built, arch welding was just making its first steps at the State Aircraft Factory. Here it was decided to use TIG welding, which was done by Rauno Pylväläinen from Patria.

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Welding was done in two phases. When the fuselage and tail assembly were fixed into jig, some points could not be welded. For those last remaining points the fuselage was moved into a rotating platform.

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After welding, the tubes were first coated with phosphoric acid, then primed with Isotrol Klarlack and finished with Isotrol color tone RAL 7005.

Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14