REPAIR INSTRUCTIONS USING FIBER GLASS MATERIAL FIBER GLASS TYPES HAND LAY-UP TYPE In the past, most fiber glass parts have been made from a hand lay-up type fiber glass.  This material is made of woven fiber glass cloth which has been impregnated with a molding resin and molded to a desired shape.  Much of the manufacturing process is done by hand as the name implies. SHEET MOLDING COMPOUND (SMC) TYPE Currently,   various   parts   are   made   from   a   newer   type fiber glass called Sheet Molding Compound (SMC). This  compression  molded  fiber  glass  differs  from  hand lay-up fiber glass in that it is made from a resin molding compound to which short or shredded glass fibers  have been    added.        The    resulting    plastic    mass    can    be compression molded to any desired shape without using cloth as is used for the hand lay-up type. RESIN TRANSFER MOLDING (RTM) TYPE A third kind of fiber glass called Resin Transfer Molding (RTM) is also being used.  This type fiber glass is similar to both hand lay-up and SMC types in that it uses a glass mat or cloth in a closed mold to which the resin molding compound    is    added.        A    room    temperature    catalyst (curing or hardening agent) is also used.  This type fiber glass also lends itself to production method of manufacture. NOTE  -  The  external  surface  appearance  of  all  three types  of  fiber  glass  material  Is  similar.    However,  the hand lay-up type material Is rough textured on Its Internal surface  (back  side)  while  "SMC"  and  "RTM"  materials are smooth. FIBER GLASS REPAIRS All   types   of   fiber   glass   repairs,   whether   cosmetic   or structural,   are   covered   on   the   following   pages.      The procedures    are    illustrated    using    the    Sheet    Molding Compound  (SMC)  type  fiber  glass.    These  procedures are also applicable and recommended for repairs to the hand lay-up type and Resin Transfer Molding (RTM) type fiber glass. NOTE - The Illustrations used in this write-up are typical and   do   not   necessarily   represent   a   particular   part   or model. TOOLS Most    of    the    hand    and    power-type    tools    (Figure    1) required to repair fiber glass or sheet metal body components  with  fiber  glass  material  are  common  tools that  can  be  found  in  any  automotive  body  repair  shop and include: Figure 1.  - Tools Required • Pneumatic     or     electric     drill     with     sanding attachment,  burr bits and tapered bits. • Sandpaper  and  sanding  discs  (24-80  grit  and 360- 600 grit). • Electric sander and sanding block. • Masking tape. • Sabre saw or hacksaw. • Assortment of clamps. • Assortment of files. • Plastic separating film. • Safety goggles & respirator mask. • Xylol, acetone or equivalent solvent. SAFETY PRECAUTIONS Observe  the  following  when  making  repairs  with  fiber glass: 1. Avoid  spilling  the  resin  or  hardener  on  skin  or clothing.  If this occurs, remove with paint thinner or denatured alcohol.  Then wash with soap and water.    If  the  mixture  contacts  the  eyes,    flush thoroughly   with   water   Immediately.      Continue flushing  for  at  least  15  minutes  and  contact  a physician as soon as possible. 2. In some cases, some Individuals may have skin sensitivity    to    the    use    of    these    materials. Because   of   this,   protective   creams   can   be applied to the hands to guard against Irritation. 3. When    protective    creams    are    not    available, rubber gloves may be used to protect the hands. The  gloves  can  be  removed  quickly  leaving  the hands clean for other work. CTS-4049 Page 3