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Body And Paint

Quarter Panel Bonding Procedure

Alot of you People building your own cars
requested the process to attach skins using
Panel Bonding Adhesive.
Quarter Panel Bonding
Step 1. Remove all trim and any glass that needs to be removed.
Step 2. Jack vehicle up in rear and support
body with jack stands(try to make car level)
remove wheel.
Step 3. Look at new panel and determine attachement points and seams.
Using a grinder(air powered is best) with 24or 36
grit disc,grind paint off at any seams where
new panel must attach, grinding lead out of seam
exposing spot welds(not necessary on partial 1/4)
Step 4.Using a spot weld drill bit,drill out spot welds.
Drilling spot welds
A. Using a wire wheel on drill or die grinder
remove paint exposing any spotwelds that you
may not see,or covered with paint on all seams.
B. using a centerpunch,punch the center of all
C.Using a spotweld cutter(Blair,Blair RotaBroach)
Drill panel till it goes thru one thickness of
metal.Drilling out each weld.
Spotwelds are located on all seams,wheel opening,
and joints.Do Not Drill Thru Metal All The Way.

D. Using a flat scraper or chisel and hammer,
slide between the two metals and pry the two
layers of metal.If metal doesn't pop apart,look
for a weld you missed or not drilled deep enough.
you may have to chisel between welds to release
if small bit of metal is holding panel.

Step 5. After drilling all welds look for any
spots that may have been brazed(brass welding)
if you find take a torch heating brass and
using a small prybar or scraper lift on panel
while heatng(Caution,Do Not Get Metal Red Hot)
torch should melt brass and release panel.

Step 6.Remove old skin. Taking a hammer
and dolly.Straighten any edges that may have
gotten bent during removal.

Step 7.Grind smooth and remove paint from
all welding flanges and seams.

Step 8.Fit new panel in place making sure
edges and body lines match adjacent panels.
Hold in place using clamps or cleeko pins.
Cleeko's are good for realigning panel during
bonding process.
On the back seam along rear bodypanel,drill
some 5/16ths holes into 1/4 skin for plug
welding it to rear body panel later.
(stitch welds can be used instead also)
Step 9.Remove new panel and place face down.
Take ginder and remove black E-coat around
inside edges(panel mateing surface)grind coating
off about half to three quarters wide.
Step 10.Apply a bead of Panel Bonding Adhesive
around inside edge of 1/4 skin, using a plastic spreader,
spread adhesive smooth covering all bare metal.

Step 11. Apply bead of adhesive on body flanges
where 1/4 skin meets,and smooth also like above.

Step 12. Apply 1/8in. bead of adhesive around
body flange surfaces.
Step 13. Place 1/4 skin on car aligning panel
to adjacent panels,making sure gaps are even
and bodylines line up.Then clamp in place
using vice grips or cleeko holding pins.
Let panel dry according to adhesive instructions.
Plug or stitch weld the rear body joint after
the adhesive has cured.
Partial 1/4 skin supplement
A. When removing old 1/4 skin cut along edge
of 1/4 leaving approx. 2 inches extra metal
underneath where top edge of partial skin stops.
B. Remove old skin and place partial skin
in place,aligning panel to adjacent panels.
C. Taking 3/4 masking tape,tape along edge of
partial skin (tape above partial 1/4 edge)
D. This step requires a flanging tool
(Air operated or hand pliers)Flange a piece
of scrap metal.Measure from edge of metal to
where crimp in metal is.Using this measurement
mark old 1/4.
E. Measure from edge of tape down to the
above crimp width measurement.cut excess metal
off to bottom of new mark.
F. Flange metal along length of old 1/4 at edge.
G. Place new partial skin in place,align panel
and check to make sure edge of panel sits
flush in flange.(trim edge of 1/4 skin if
H. Clamp new panel in place(aligning gaps and
body lines) drill 1/8th in. holes thru
1/4 skin along seam halfway down from edge of
old and top of new panel.Secure with cleeko pins
or screws.
I. remove panel and grind coating off inside
of partial 1/4 approx. 1/2 in. down from edge.
grind any paint along old 1/4 edge.
J. Apply a liberal amount of adhesive to both
old 1/4 and new skin using same method as
above mentioned process. apply the 1/8th in.
bead of adhesive along flange and place 1/4 skin
in place.
K. align skin and put cleeko's or screws in
excisting holes along seam.Use Above method
for attching the other areas of 1/4 skin.
Let adhesive dry then smooth seam with grinder.
(Weld rear body seam as mentioned in above)
L. After removeing cleeko's and smoothing seam
with grinder,apply a coat of either
Duraglass filler or All Metal filler over seam.
smooth seam straight with sanding block
and 36 grit sand paper.
M. Finish seam with body filler then sand and
prime panel.(Inside trunk seam of 1/4 can be
smoothed over with above method then sprayed
with Paintable Rubberized Undercoating & Painted)

Tools and Materials Required
4-5 in. grinder with 24or 36 grit discs

Panel Cutter(cut-off tool or shear type)

Flat scraper or chisel

Body Hammer and Metal dolly

SpotWeld Cutter( Blair double blade or Blair
RotaBroach Cutters work best)

Cleeko panel holding pins or 1/8th in.screws
Cleeko Pliers

Flange Tool (Air operated or hand pliers)

SEM or 3M Panel Bonding Adhesive & Applicator gun
(SEM applicator gun is cheapest-Approx. $60)
(3M App. Gun is Approx. $130-$150)
Wire Feed welder for plug or stitch welding
rear body seam.
3/4 in. Tape
Pencil or Marker(Sharpie)
Sanding Block and 36 grit paper
Duraglass or All Metal filler
Body filler and Sandpaper
Paintable Rubberized Undercoating


Well if I believe the rep that sells the stuff to me, he says you can take two pieces and overlap them 1/4 inch with the adhesive then play tug-o-war with the metal between two frame machines and the metal will tear before the adhesive.
As far as acidents we were told never to use the stuff on frames etc as it will be strong enough to eliminate the crumple zones.
Can't answer as far as heat (or cold for that matter) or value but consider the following.

No gaps between spotwelds, a 100% seal all the way around, no place for moisture to hide between panels.

No laying down on your back trying to mig over your head.
No grinding down spot welds, which not only saves time but $ in discs.
The most heat generated is from grinding the surface to be preped, no welding near flamable stuff or worrying about catching carpets on fire etc.
Other then trying to duplicate the look of a factory spot weld, I see no advantages of welding over the adhesive unless you are good enough to butt (SP?) weld.
Just my but I havn't used the stuff since I left the bodyshop a few years ago, If anything I'm sure theirs alot of improvents since I've used it.



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