Ford F-150 2015 - Hem Flanges

Module�3�-�Aluminum�Joining�MethodsTextbook
2015�Ford�F-150�Structural�Repair�Training�Course�(FOR06) 44
Rivets�are�always�used�with�adhesive.
When�preparing�to�attach�a�rivet-bonded
part,�identify:
• which�type�of�rivet�or�rivets�are
recommended�by�the�vehicle
maker.
• if�a�hole,�dimpling,�or
countersinking�is�necessary.
• which�type�of�clamps�will�be
required.
• what�preparation�steps�are
required�for�the�mating�flanges.
• the�proper�adhesive�and
application�requirements.
Hem�Flanges
A�rope�hem�flange�is�designed�to�prevent�cracking�as
it�is�being�made.
Hem�flanges�are�commonly�used�on:
• door�skins.
• wheelhouse�flanges.
Aluminum�hem�flanges�are�made�at�the
vehicle�maker�before�the�6000�series
aluminum�is�bake-hardened.�By�doing
this,�the�aluminum�is�formed�while�it�is
still�soft.
A�rope�hem�flange�is�used�for�installing
replacement�parts�that�are�already
heat-treated.�A�rope�hem�flange�allows
for�a�larger�radius�to�be�made�as�the
replacement�panel�is�installed�on�the
part.
Thicker�material�will�be�more�difficult�to�roll�a�flange
without�cracking.
When�hemming�a�panel,�consider�the:
• alloy�of�the�aluminum.�Some
alloys�like�5XXX�series�alloy
materials�get�their�strength�from
work�hardening.�This�means�as
the�flange�is�being�rolled�over
and�set,�the�area�where�the�part
is�being�bent�is�gaining�strength.