TM 55-8115-203-23 & P
(8) Bevel to a thirty degree angle the rail edges which will butt against the corner fittings.
(9) Tack weld the replacement rail in place. Check standard dimensions according to figure 3.1 and adjust
(10) Continuously weld the rail to the corner fittings, roof panels and side or end panels.
(11) Paint the replacement area according to procedure 2-4.
(12) Test for weatherproofness using procedure 2-5. Caulk if necessary.
3-6. Bottom Rail. Avoid using heat when repairing the bottom rail. Use repair procedures in the following order of
preference: Filling with weld metal welding repair with inserts, sectioning and replacement of the rail.
All patches, inserts, sections and replacements for panels, rails and crossmembers should be
steel conforming to the AISI-409 standard. AISI stands for the American Iron and Steel
Institute. This steel is corrosion resistant and has a minimum tensile strength of 65KSI
(thousand pounds per square inch).
a. Repair of small cracks and tears. Small cracks and tears less than two inches in length should be filled with
(1) Carefully smooth ragged edges of tear with file or hammer before welding.
(2) Grind along length of crack. Grind crack to depth of 3/16 in. (5 mm or 5/6 of metal thickness) to ensure
full weld penetration.
(3) Continuously weld along length of crack.
(4) Paint according to procedure 2-4.
b. Inserting. If the damaged bottom rail cannot be repaired by gouging and welding the bottom rail may be
repaired by inserting. The minimum length of bottom rail inserts is six inches.
(1) Restrictions for insert repair of bottom rails are as follows.
(a) The insert must be at least six inches long. See figure 3-9, example A.
(b) New inserts must end at least six inches from existing inserts or other vertical welded seams. If the
area to be repaired is closer than six inches to an existing vertical welded seam, the insert must extend
to meet the existing vertical welded seam. See figure 3-9, example B.