Blocking and bracing materials and their applications

TM 38-260

make irregular-shaped items fit a regular-shaped container and to distribute the weight of irregular items over the

maximum surface area of the container.

(1) Blocking and bracing may be used to modify the original shape of an item so that it is protected adequately

and so that it fits the container.

(2) Materials used for blocking and bracing differ from cushioning in that they are not intended to absorb shocks.

Items having legs or other projecting parts which may become loose or broken or which might puncture the container

must be supported by adequate blocking and bracing.

(3) Blocks and braces shall be applied against portions of the container that are strong enough to resist forces

tending to distort them. Likewise, the bracing should be arranged to distribute forces to several reinforced sections of the

surface of the item.

c. Blocking and bracing materials and their applications. Materials used for blocking and bracing shall be strong

and rigid. The greater the need for support, the stronger and more rigid the materials must be.

(1) Use of lumber. Lumber used in blocking and bracing shall be free from cross grain and should not have knots

located near the center of a piece that is being used as a beam or column. If knots cannot be avoided, the following

should be carefully considered:

(a) Edge knots shall be placed so that the knots will always be in compression.

(b) Center knots shall not have a diameter greater than one-fourth the width of the piece of lumber.

(d) Thin pieces of wood split more easily than thick ones; therefore, thin pieces should not be used in blocking

unless precautions are taken against splitting. If thin boards are used, do not nail too close to the edge of the board, use

the correct size of nail, predrill holes for nails, and reinforce the board with a facing of plywood.

(e) All braces should, if possible, have their edges against the article in order to utilize their maximum strength. If

it becomes necessary to have the flat face of the brace against the article, the size of the brace must be increased.

(f) When bases of ordinary lumber are used, they shall be constructed with sufficient cleats at right angles to the

grain of the base boards and securely fastened with clinched nails to prevent the boards from splitting at the bolt holes.

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