TM 5-3895-373-34 a. Screed    Tow    Point:        The    main    screed assembly  is  attached  to  the  tractor  on  each  side  of  the paving machine.  These points of attachment are known as the  screed  tow  points.  The  attachment  is  made  by  a metal flange plate to flange plate connection between the screed arm and screed tow arm. b. Screed Control Panels:  The screed control panels are located on both the left and right sides of the screed.      Each   control   panel   protective   cover   can   be removed     to     gain     access     for     repairs.          The     wire connections  inside  the  control  box  are  composed  of  pin connectors and hard soldered joints.  Both screed control boxes    have    identical    control    switch     functions     and indicators,  with  the  exception  that  the  left  control  box  is also  configured  with  a  fuel  pump  switch  and  indicator. The dual screed control box configurations allow  for  the positioning  of  two  screed  operators,  or  allows  a  single screed  operator  convenient  access  to  controls  for  safe machine  operation.    The  screed  control  boxes  contain the following switches: (1) Extension Screed Control (2) Extension Screed Blower (3) Extension Screed Burner Control (4) Tow Point Movement (5) Auger/Conveyor Reverse Control (6) Feeder Control (7) Flow Gate (8) Emergency Stop (9) Fuel Pump (left control panel only) (10) Main Screed Blower (11) Main Screed Burner Control (12) Panel Light c. Extension Screeds:  The extension screeds are   hydraulically   operated   with   two   extension   screed height  adjustments  mounted  on  each  extension  screed to control the desired slope.  The height adjustments can be   raised   or   lowered   independently   of   each   other   by removing  a  quick  release  pin  from  the  adjusting  wheel shaft.      Quick   release   pins   are   not   removed   from   the adjusting    wheel    shaft    if    the    same    adjustments    are required. d. Thickness Control:  Paving mat thickness is changed  by  altering  the  setting  of  the  thickness  control, which changes the angle of the screed in relation to the surface  being  paved.    This  is  referred  to  as  angle  of attack.    The  thickness  control  is  operated  by  a  manual hand crank mounted in a mounting bracket supported by two roller bearings.  The hand crank shaft is attached to a  universal  joint  which  is  connected  to  a  threaded  rod and link bolted to the screed arm. e. Screed Vibrators:  The screed vibrators are hydraulically  driven  and  operated  by  toggle  switches  on the    operator    control    panel.        The    main    screed    is configured     with     two     vibrators     connected     with     two universal   joints   on   rotating    shafts.        Each    extension screed is configured with one vibrator each. f. Screed   Burners/Blowers:      The   screed   is equipped with four independently controlled burners and blowers  to  increase  the  temperature  of  a  cold  bottom screed   plate   to   approximately   300°F   (150°C).      The burners   are   diesel   fuel   atomizing,   configured   with   a burner chamber and an internal fuel nozzle.  Each burner chamber has a glow plug used for the fuel ignition.  Each burner is also equipped with an exhaust heat distribution duct   to   deflect   the   hot   air   evenly   across   the   screed plates. Each fuel burner has a blower assembly driven by a 12 volt  DC  motor  mounted  on  support  brackets.    The  fuel burner is attached to the blower with a steel flexible pipe connected    at    the    blower    exhaust    and    the    burner chamber inlet. 1-22