Components, contact, and open time determine the result.
Product and application
Select the system so that only relevant test steps appear. If no system is specified, the test will remain general.
01
What are you observing?
02
Identify the cause
03
For reference
All test steps in this guide can be used even without the guided process.
Terms briefly explained
Hand strength
The parts should be handled carefully. The connection is not yet fully load-bearing.
Complete curing
The curing conditions and times prescribed for the product were adhered to.
Adhesive gap
Distance between the two joining surfaces, not the length of the adhesive seam.
Pot life and nozzle life
Test the processability of a mixed quantity and the processability in the mixing nozzle separately.
Does not harden or only hardens in places; 3 test steps
Distinguish between resin/initiator systems and mixed A/B systems.
1 · Mixture
Do the components, mixing ratio and mixing nozzle match the product data sheet?
Uneven application or unsuitable nozzles will leave unmixed areas. A general mixing ratio does not apply to all products.
Check the correct resin/hardener combination and prescribed ratio.
Check the cartridge piston, the discharge of both components, and the recommended mixing nozzle; pre-run the nozzle according to the manufacturer's instructions.
For dosing systems, check the actual quantities of both components. Document any streaks or unmixed areas.
2 · Contact & Joint
Do the reactants meet completely within the permissible joint?
When applying without a mixing nozzle, the beads must meet correctly. Uneven materials can create gaps that are too large in places.
In the caterpillar-on-caterpillar method, the caterpillars are placed on top of each other instead of next to each other.
Check contact, ratio and maximum gap from the respective TDS; hold the joint still during the reaction.
3 · Storage
Has the material been stored within its shelf life and according to the data sheet?
Aging, humidity, separation of components or unsuitable temperatures can alter processing and hardening.
Record batch number, expiry date and inventory history.
Check for segregation, thickening, and contamination. Do not correct conspicuous material with unauthorized additives.
If the material quality is unclear, check a fresh, correctly stored batch for comparison.
Adhesive becomes viscous; 2 test steps
MMA monomer can evaporate if the container is open or if it remains open for too long.
1 · Storage
Has the material been stored within its shelf life and according to the data sheet?
Aging, humidity, separation of components or unsuitable temperatures can alter processing and hardening.
Record batch number, expiry date and inventory history.
Check for segregation, thickening, and contamination. Do not correct conspicuous material with unauthorized additives.
If the material quality is unclear, check a fresh, correctly stored batch for comparison.
2 · Open time
Does the material remain sealed until processing, and is the joint joined quickly?
Monomer loss can also impair subsequent strength.
Bring the container to room temperature before opening it.
Do not spread MMA adhesive too widely or leave it exposed for long periods of time.
If applying separately, first prepare the initiator, then apply the adhesive as a bead and join promptly – according to product specifications.
Initiator clumps or gels 2 test steps
Distinguish between unopened material and a container that has already been used.
1 · Clean extraction
Are only clean tools used, without any back-transfer?
A brush that alternately touches the component and the container can contaminate the initiator.
Use clean or fresh brushes; avoid cross-contamination.
In case of an unopened, conspicuous container, report the batch and transport/storage history to Permabond.
2 · Storage
Has the material been stored within its shelf life and according to the data sheet?
Aging, humidity, separation of components or unsuitable temperatures can alter processing and hardening.
Record batch number, expiry date and inventory history.
Check for segregation, thickening, and contamination. Do not correct conspicuous material with unauthorized additives.
If the material quality is unclear, check a fresh, correctly stored batch for comparison.
Stress cracks in plastic: 3 test steps
Incomplete mixing and uncured residues can damage the plastic.
1 · Mixture
Do the components, mixing ratio and mixing nozzle match the product data sheet?
Uneven application or unsuitable nozzles will leave unmixed areas. A general mixing ratio does not apply to all products.
Check the correct resin/hardener combination and prescribed ratio.
Check the cartridge piston, the discharge of both components, and the recommended mixing nozzle; pre-run the nozzle according to the manufacturer's instructions.
For dosing systems, check the actual quantities of both components. Document any streaks or unmixed areas.
2 · System selection
Has a system that reliably hardens completely been selected?
The guide mentions fast-curing 1:1 products with a mixing nozzle as a possible alternative.
Check a suitable mixed system.
Demonstrate compatibility and hardening on the specific plastic.
3 · Surface
Are the actual materials clean, dry, and properly prepared?
Oil, release agents, varnishes, and weak oxide layers can impair adhesion. Changing suppliers can also alter the surface.
Determine the material and alloy or plastic mixture. Ask the supplier about any changes to release agents, plasticizers, and coatings.
Adjust the cleaning process to the material and allow the cleaning agent to evaporate completely. Check the blasting media for cleanliness and condition.
Apply adhesive promptly after pretreatment and avoid further contact or oxidation. If necessary, test wettability using suitable testing methods.
Disturbing Odor 1 Test Steps
Capture MMA fumes at their source.
1 · Extraction
Is effective local suction in place?
The odor nuisance also depends on the workplace and air circulation.
Check the extraction system and airflow.
Consider using acrylates with lower odor, such as the TA452/TA4522 mentioned in the source, or another suitable technology.
Insufficient strength: 3 test steps
First, define the fracture pattern and then examine the surface, application, and load.
1 · Surface
Are the actual materials clean, dry, and properly prepared?
Oil, release agents, varnishes, and weak oxide layers can impair adhesion. Changing suppliers can also alter the surface.
Determine the material and alloy or plastic mixture. Ask the supplier about any changes to release agents, plasticizers, and coatings.
Adjust the cleaning process to the material and allow the cleaning agent to evaporate completely. Check the blasting media for cleanliness and condition.
Apply adhesive promptly after pretreatment and avoid further contact or oxidation. If necessary, test wettability using suitable testing methods.
2 · Order & Fixing
Is sufficient adhesive applied to the correct area and is the joint held still during the curing process?
Gaps in the order, incorrect contact points, and movements during curing can explain local failures.
Check the dosage and actual wetting of the contact surface.
Maintain fixation until the required strength is achieved; pay attention to air gaps and torn structures.
Document the error rate and distribution. Individual failures may indicate fluctuating process conditions.
3 · Load
Is the bond only subjected to stress within its operating conditions after sufficient curing?
Premature stress, peeling forces, media, or differing thermal expansion can weaken a connection that initially appears to be good.
Compare the waiting time before loading with the product data sheet.
Capture joint geometry, temperature, chemicals and humidity in real-world use.
For peeling loads or different materials, test tougher or more flexible systems with the application engineer.
German version prepared according to the archived Permabond guide troubleshooting-structural-acrylics.md. Always compare product-specific values and procedures with the corresponding technical data sheet.
