Porshe 911 (997). Manual - part 1211

Item

Designation

Item

Designation

-B1-

Piston rod

-C1-

Double cartridge

-B2-

Gun grip

-C2-

Processing nozzle

Information on the use of structural adhesives in vehicle
construction

General

Structural bonding in the body shell means that the adhesive assumes functions of stiffness, crash strength and
endurance strength, whereby the characteristics of the body shell are positively influenced in a significant
way. In a conventional steel body shell, use is made of a high-strength, heat-hardening single-component
epoxy resin adhesive that fully hardens in the cathodic immersion paint drying oven. In the case of a repair,
this adhesive is replaced by a cold-hardening two-component epoxy resin adhesive, since the hardening
temperatures necessary for the single-component epoxy resin adhesive are not conceivable on an assembled
vehicle. For both series production of bodies-in-white and repair, structural bonded joints are regularly used in
combined jointing processes.
Resistance spot-welding combined with adhesive bonding and mechanical jointing processes
In the case of spot weld bonding for repair and series production, the entire extent of adhesive surfaces and
spot welds is replaced. In this case, before actually spot weld bonding, the unhardened adhesive must be
displaced from the joint area by an appropriate squeeze time. In the case of two-component adhesives, the
hardening reaction starts immediately after mixing and application; this increases the viscosity and so there is
only a certain time window in which spot weld bonding can be performed if the process is to be reliable. For
this reason, all time-intensive preliminary work (drilling, cutting to size, fixing etc.) on the parts to be joined
must be performed before application of adhesive and jointing. This also applies to mechanical jointing
processes where the adhesive has to be displaced from the joint area.

Separating body components

Diagnostic system: reading out fault memory and activating systems

Processing structural body adhesive

5001

Separating body components

In the case of 3-layer spot-welded panel joints with a hardened bonded layer in which only the outer panel
needs to be replaced, drill the outer panel in the area of the spotwelds sufficiently well without damaging the
spotweld and bonded joint in the second component layer.

Separating bonded body components

In the case of 3-layer spot-welded panel joints with a hardened bonded layer on the outer panel, drill the outer
panel in the area of the spotwelds sufficiently well without damaging the spotweld in the second component
layer. After removing the loosened body part, old adhesive must be removed and any uneven spots sanded
down. The flange area must then be pre-treated for bonding.

Welding in body components

Spot-welding body components

Note

In areas in which bonded flanges are spot-welded in an unhardened state, suction devices must be
used due to combustion products.

• 

Areas that can only be accessed from one side must be joined with MAG plug-welds or MAG welded
seams. In these cases, no adhesive can be used in the vicinity of the welded seam because this would
burn and would have a negative effect on the joint.

• 

The areas without adhesive must be protected using appropriate anti-corrosion and sealing measures.

• 

Once the spare parts have been attached, repair spotwelds must be placed on the old spotwelds because there

Diagnostic system: reading out fault memory and activating systems

Separating body components

5002

is no current flow possible in areas with a hardened bonded layer. Welding procedures other than resistance
spot-welding are not permitted since the thermal effect would destroy the bonded joint over a wide area.

Spot-welding body components

Processing adhesives

ATTENTION

Danger of poisoning and injury when handling adhesive!

Danger of poisoning from breathing in vapours or from swallowing adhesive.

• 

Risk of injury due to contact with skin or eyes.

• 

→ Ventilate the work area well.

→ Do not eat, drink, or smoke while carrying out work.

→ Avoid direct contact with eyes and skin. Wear suitable protective equipment, such as protective

clothing, gloves, and if necessary, a protective mask.

→ If clothing is soiled with adhesive, change clothing immediately and only use again after they

have been cleaned.

→ Also observe the product-specific processing and safety instructions on the packing container and

packing container imprints.

→ In case of eye contact: Rinse eyes immediately and thoroughly with lukewarm running water and

consult an eye doctor.

→ In case of skin contact: Rinse contacted skin areas immediately with lukewarm running water and

soap.

→ If adhesive is swallowed: Rinse mouth and consult a doctor.

Note

Bonding surfaces must be free from oil, old adhesive, dirt, moisture, and layers of paint and oxide.

• 

Body structural adhesive and primer must only be used on bare metal parts.

• 

Diagnostic system: reading out fault memory and activating systems

Welding in body components

5003

Ensure that clean gloves are worn when touching cleaned surfaces to avoid transferring sweat from
the hands and dirt onto the bonding area.

• 

The jointing operation must take place directly after application of the adhesive in order to guarantee
a high quality and reliable bond. Otherwise the adhesive bead must be removed, with pre-treatment of
the surface and application of the adhesive being repeated.

• 

After adhesive has hardened, carefully prime accessible bonding areas and seal with body sealant.
Protect bonding areas in cavities with cavity preservation against corrosion.

• 

Preparing adhesive flanges
To improve adhesion, the bonding surfaces must be roughened using sandpaper with a grain of 100 to 150.
Remove paint layers (cathodic immersion painting) using dry sandpaper or fibre discs with a grain of 100 to
150. The bare bonding surface must then be cleaned with a lint-free cloth soaked in acetone. Leave cleaned
areas to dry for approx. 1 - 2 minutes; bonding surfaces must be completely dry. Apply primer to the cleaned
surfaces. →  2-K-SIP
Bonding operation
Minimum ambient and material temperature during working and hardening is 18° C. The coating thickness of
approx. 1 mm should not be exceeded; if necessary, spread the mixed adhesive on the bonding surface with a
spatula. Areas not covered by cathodic immersion painting and exposed body panels in cavities must be
brushed or filled with structural adhesive.
Jointing operation
Join, fix and resistance spot-weld parts within the working time. The jointing operation must take place
directly after application of the adhesive in order to guarantee a high quality and reliable bond. Otherwise the
adhesive bead must be removed, with pre-treatment of the surface and application of the adhesive being
repeated.
Remove excess material
Remove most of the excess material with paper or cloth. Finish cleaning visible surfaces with a cloth soaked
in acetone. Hardened material can only be removed mechanically.
Hardening
The body structural adhesive used hardens at room temperature. Hardening can be accelerated by heat (e.g.
with an infra-red radiator in a painting booth). Do not load bonded parts until hardening is complete.

Betamate 2096
adhesive set

Initial strength at 23 °C

Approx. 10 h 1)

Initial strength at 60 °C

Approx. 2 h 1)

Hardening time at room temperature (23 °C)

Approx. 170 h

1) After this time assembly work is permitted

Corrosion protection
After adhesive has hardened, carefully prime accessible bonding areas and seal with body sealant. Protect
bonding areas in cavities with cavity preservation against corrosion.
Further work on the vehicle
The time from joining the repaired components to handing over the vehicle to the customer must be at least 48
hours. After repairs with adhesive, allow at least ten hours before moving or carrying out further work on the
vehicle (leave standing overnight) to avoid damage to the bonded joint by premature loading.

Diagnostic system: reading out fault memory and activating systems

Processing adhesives

5004