micrometer setting types (fig. 2-35). When using the deflecting  beam  and  the  dial  indicating  torque wrenches, the torque is read visually on a dial or scale mounted on the handle of the wrench. To use the micrometer setting type, unlock the grip and adjust the handle to the desired setting on the micrometer-type scale, then relock the grip. Install the required socket or adapter to the square drive of the handle. Place the wrench assembly on the nut or bolt and  pull  in  a  clockwise  direction  with  a  smooth, steady motion. (A fast or jerky motion will result in an improperly torqued unit.) When the torque applied reaches the torque value, indicated on the handle set- ting, a signal mechanism will automatically issue an audible  click,  and  the  handle  will  release  or  “break,  ” and  move  freely  for  a  short  distance.  The  release  and free travel are easily felt, so there is no doubt about when  the  torquing  process  is  complete. Manufacturers’ and technical manuals generally specify  the  amount  of  torque  to  be  applied.  To  assure getting the correct amount of torque on the fasteners, it is important that you use the wrench properly ac- cording  to  manufacturers’  instructions. Use that torque wrench that will read about mid- range  for  the  amount  of  torque  to  be  applied.  BE SURE THAT THE TORQUE WRENCH HAS BEEN CALIBRATED BEFORE YOU USE IT. Remember, too,  that  the  accuracy  of  torque  measuring  depends  a lot on how the threads are cut and the cleanliness of the  threads.  Make  sure  you  inspect  and  clean  the Figure   2-35.—Torque   wrenches. threads.  If  the  manufacturer  specifies  a  thread  lubri- cant,  it  must  be  used  to  obtain  the  most  accurate torque reading. When using the deflecting beam or dial indicating wrenches, hold the torque at the de- sired value until the reading is steady. Torque   wrenches   are   delicate   and   expensive tools. The following precautions should be observed when using them: 1. When using the micrometer setting type, do not move the setting handle below the lowest torque setting. However, place it at its lowest setting before returning it to storage. 2. Do not use the torque wrench to apply greater amounts of torque than its rated capacity. 3. Do not use the torque wrench to break loose bolts  that  have  been  previously  tightened. 4. Do not drop the wrench. If dropped, the accu- racy will be affected. 5. Do not apply a torque wrench to a nut that has been tightened. Back off the nut one turn with a nontor- que wrench and retighten to the correct torque with the indicating  torque  wrench. 6.  Calibration  intervals  have  been  established  for all torque tools used in the Navy. When a tool is cali- brated by a qualified calibration activity at a shipyard, tender, or repair ship, a label showing the next calibra- tion due date is attached to the handle. This date should be checked before a torque tool is used to ensure that it is not overdue for calibration. MICROMETERS The type of micrometers commonly used are made so the longest movement possible between the spindle and the anvil is 1 inch. This movement is called the range.  For  example,  a  2-inch  micrometer  has  a  range from 1 inch to 2 inches, and only measures work be- tween  1  and  2  inches  thick.  Therefore,  you  must  first determine the approximate size, to the nearest inch, of the piece to be measured and then select the proper size micrometer. The size of a micrometer indicates the size of the largest work it can measure. Outside   Micrometer The  nomenclature  of  an  outside  micrometer  is illustrated in figure 2-36. 2-24