TM 1-1500-204-23-3 (2) Internal  and  External  Loose  Seams  (Lap or Splice, Edge, or Fitting Flange), With Up to 1/4 Inch of Material Missing or Damaged.. WARNING Acetone  and  repair  adhesives  are flammable  and  toxic.    Keep  away from heat, sparks and open flame. Wear  safety  glasses,  gloves  and protective     clothing     to     prevent contact.  Wear a NIOSH approved air-purifying respirator for organic vapors and work in a well ventilated area.  If contact occurs, flush   areas   with   water   and   get medical   attention.      H   ingestion occurs   get   medical   attention   at once. (a)    Gently  pull  back  loose  seam,  etc. and   dean   area   to   be   bonded   using   a   piece   of   dean cheesecloth    (item    16,    table    2-11)    dampened    with acetone (item 3, table 2-11).  Wear gloves (item 4, table 2-11). (b)    Lightly,  hand  buff  both  surfaces  to be bonded. (c)    Clean buffed areas using a piece of dean  cheesecloth  (item  16,  table  2-11)  dampened  with acetone (item 3, table 2-11).  Wear gloves (item 4, table 2-11).  Allow cleaned areas to dry. WARNING Repair adhesive is flammable and should   be   kept   away   from   any ignition source. NOTE Adhesive materials should be kept tightly sealed in individual containers in a cool, dry place. (d) Refer to paragraph c(1)(e) for mixing instructions. NOTE Do   not   apply   adhesive   beyond buffed areas. NOTE The    adhesive    should    be    used sparingly.        Two    (2)    thin,    even coats will provide better adhesion than   two   thick,   puddled   coats. Acetone  is  used  as  a  solvent  for the adhesive and, when the cemented  surface  appears  dry  to touch,   it   may   be   freshened   or made  tacky  again  by  application of this solvent. (e)    Brush   coat   buffed   areas   with   one coat of adhesive and allow to dry 20-60 minutes. NOTE To determine if adhesive is tacky, test    it    by    pressing    a    knuckle gently against the cemented surface    and    withdrawing    it    (if practical).      Proper   tackiness   is achieved  when  a  few  threads  of adhesive    stick    to    the    knuckle. This  procedure  is  referred  to  as the knuckle test. (f)    Apply   a   Second   coat   of   adhesive (item  18,  table  2-11)  to  buffed  areas  and  allow  to  dry until  tacky.    Adhesive  can  become  tacky  within  2  to  4 minutes,     depending     on     ambient     temperature     and humidity. (g)    If  necessary  to  restore  tack  to  the cemented  surfaces,  use  a  piece  of  dean  cheesecloth (item  16,  table  2-11)  dampened  with  acetone  (item  3, table  2-11),  lightly  wipe  over  cemented  areas.    Allow solvent to evaporate 10 to 20 seconds or until cemented areas  become  "tacky."  NOTE  If  adhesive  dry  times  for the  second  coat  is  exceeded,  application  of  one  more coat of adhesive may be done, for a total of three coats. If   dry   times   for   all   three   coats   are   again   exceeded, remove  all  adhesive  from  applied  area  using,  acetone and/or buffing with emery cloth (120 grit minimum). (h)    Press cemented surfaces together. (i)    With   a   one-inch   or   smaller   roller (item 20, table 2-11), roll over repaired area to remove any trapped air. (j)    Place   a   10   to   25   pound   force   by damping (C-damp (item 21, table 2-11) and two pieces of wood (item 22, table 2-11)), shot bag (item 23, table 2-11),  etc.,  if  practical  on  repair.    Polyethylene,  waxed paper   (item   24,   table   2-11),   or   equivalent   should   be placed  between  the  repaired  area  and  force  applying device, to prevent sticking of the force applying device to the repair. Change 2  2-59