Pillow and mattress patches were installed from the exterior. While interior patches required less to no rigging, they were quicker, less complicated, safer and usually secured with wooden, steel angle or pipe shoring. For some holes protruding outward, Sailors installed a prefabricated patch on the inside, securing it with T, J, L or folding “T” bolts, a line with turn buckles, or shoring. Using these methods and procedures, they patched areas where rates of flooding were the highest first.

During damage repairs, reports were made to the on scene leader when the hole was under repair, the flooding rate, when the repairs were completed, when the compartment was being dewatered, upon completion of dewatering and residual leakage, if any.

1. Pillow Patch
   This method of temporary DC repair was quick, simple and required few personnel. Prefabricated materials could be used, or personnel could improvise a suitable patch.
    
   For holes protruding inward, an excellent patch could be quickly made with a pillow with a hole punched in the center. The back-up board and plate also had to have a hole in the center. A stout line was passed through the padding and board and knotted on each side of the patch assembly securely. The entire patch was then placed on the outside of the hole and hauled into position. The weighted, bitter end of the line was passed through the hull hole. A Sailor retrieved the line and attached it around a stanchion. A Spanish windless was fabricated to take in the slack and create tension on the patch line until it was securely pulled into place. Once secured, they tied it off and secured the Spanish windless to prevent it from unwinding.
    
   For holes protruding outward, the patch was installed on the inside and secured with either a T, J L or folding “T” bolts and a line with turn buckles; otherwise it could be shored it in place.
    
   A boatswain’s mate second class (BM2) was in charge, with three personnel required to fabricate, rig and install the patch. They were usually one boatswain’s mate and two damage controlmen (DCs) or carpenter’s mates from repairs 1 and 3 and their unit lockers.
    
    
2. Mattress Patch
   Mattress patches were used on damage generally caused from shell, bomb or torpedo fragments. This method of temporary DC repair took more time, was more difficult to fabricate and rig, was more risky and required more personnel.
    
   To fabricate the mattress patch, Sailors started by drilling two holes through a mess table top and mattress. They ran two ¾- by 10-inch long threaded eye hook bolts through the holes in the table top, then inserted large washers and backing plates. Oakum was wrapped around the throat of the bolt stock on each side, between the nuts and washers, to reduce leakage. The bolts were then tightened to a snug fit. They also drilled 5/8-inch holes in each end of the table or backing plate to insert and tie off ½-inch guy lines. A 1-inch by 25-foot line was inserted through the eye hooks. For weight to facilitate catching the line and hauling it in through the damage hole, Sailors attached a large set of steel washers or metal “O” rings on the bitter end of the line.
    
   As the mattress patch was lowered over the side, guy lines were used fore and aft to control the movement and guide the patch into place. A Sailor stood by in the designated damaged compartment below decks to retrieve the line and patch, pull the bitter end of the line through the damage hole opening and attach it around a stanchion or other stable structure. A Spanish windless was fabricated to take in the slack and create tension on the patch line until it was securely pulled into place. Once secured, they tied it off and secured the Spanish windless to prevent it from unwinding.
    
   A boatswain’s mate first class (BM1) was in charge because of the rigging and safety involved, with four to five personnel required to fabricate, rig and install the patch. The team usually came from repairs 1 and 3 and their unit lockers and included one boatswain’s mate for rigging, two damage controlmen (DCs) or carpenter’s mates to fabricate and assist in rigging, and one shipfitter-metalsmith (SFM) for welding if required and fabrication.
    
    
3. Box Patch
   This method of temporary DC repair was quick, simple and required fewer personnel than pillow or mattress patch methods. Prefabricated materials could be used, or personnel could improvise a modified patch to match the damaged hull configuration.
    
   Patching for holes protruding inward, and especially for holes with jagged edges sticking inboard, were miniature cofferdams or open box patches. It could be made of either wood or metal. The open wooden box was usually 18 inches square and 6 inches deep. It could be made and shaped to fit the contour of the hull, fitted with a rubber gasket, placed over the hole, and shored in place. The steel boxes were fabricated with the same dimensions, with a rubber gasket glued around the 1-inch face of the box patch and welded with angle iron. “L”-shaped clips, 4 by 1 ½ by 1 ½ inches, were welded on top for shoring anchor points. Some box patch sizes were prefabricated and stored near the repair lockers in each section of the ship.
    
   A damage controlman (DC) or carpenter’s mate was in charge and assisted, with one shipfitter-metalsmith (SFM) for welding, fabrication and installing the patch. These personnel were usually from repairs 2, 3 or 5.