Aviation Form-A-Gasket No. 3
Non-hardening gasket sealant · US · manufacturer-sourced
How long before you can put Permatex Aviation Form-A-Gasket No. 3 back into service?
Short answer
Gasket-sealing stages
Assemble, wait, then fill and pressurize
- Apply the Non-hardening gasket sealant to clean, dry flanges
- Assemble within the stated time
- Fill and run only after the stated cure
This product’s stated stages Quoted at 73°F
- Return to service4 hours
- Full cure1 day
Worth noticing: Return to service at 4 hours; full cure at 1 day.
Common mistake: Adding fluid or pressure before the gasket has cured; leaks follow.
Bond-strength path
Assembly, handling and full load are different stages
Time the gasket cure
Your countdown
Stated times
- Return to service4 hours
- Full cure1 day
From Permatex data sheet · checked 2026-10-25. Anything not listed isn’t stated by the manufacturer.
Manufacturer website: permatex.com
Conditions & fine print
- Stated conditions: 73°F (23°C)
- Times depend on temperature, humidity, film or bead thickness and airflow. Follow the current data sheet and label.
- Region US. Formulas can differ between countries; check your container.
- Return to service: Dry times vary with temperature, humidity and gap.
- Full cure: Dry times vary with temperature, humidity and gap.
- Entered from the cited manufacturer documentation. Check the current label for the exact formula and region. Report outdated information
- Actual results depend on preparation, thickness, ventilation, temperature, humidity, mixing and substrate.
Confirm this is your product
Closely named formulas, colors and regional versions can use different times. Match these details to your container before starting a countdown.
- Exact listing
- Permatex Aviation Form-A-Gasket No. 3
- Variant
- Non-hardening gasket sealant
- Region
- US
- Listed use
- gaskets
- Timed stages recorded
- return service, full cure
- Source checked
- 2026-10-25
Documentation: Technical data sheet copy · AAM Revised 03/18
Condition attached to the stated time: Dry times vary with temperature, humidity and gap.
About this product
A slow-drying gasket sealant formulated to give more work time. It never fully hardens, staying a pliable, tacky film as the solvent leaves. The sheet says the assembly is operational after 4 hours and fully cured at 24, with continuous service from -65 to 400°F.
Using this specific product
Permatex Aviation Form-A-Gasket No. 3 is listed here as the Non-hardening gasket sealant version for gaskets. For using this product, the useful question is not simply whether the surface looks finished—it is whether the exact next-action milestone shown above has been reached.
Before you start
- Confirm the package says Non-hardening gasket sealant; related versions can use different timing.
- For gaskets, pay particular attention to the exact variant, preparation and environmental conditions.
- Dry times vary with temperature, humidity and gap.
How to check readiness
Check the real material or treated area at the slowest location before the next step. The data sheet says the assembly is operational after 4 hours. Reserve full cure for demanding use, chemicals, washing, immersion or load—not merely gentle handling.
Avoid this mistake
The first visible change is not always the manufacturer’s final-use milestone.
Questions
How long before you can put this product back into service?
Permatex states: The data sheet says the assembly is operational after 4 hours. Conditions: Dry times vary with temperature, humidity and gap.. The data sheet says full cure is effective after 24 hours. Conditions: Dry times vary with temperature, humidity and gap.. These are the manufacturer’s stated times, not a guarantee.
Does Aviation Form-A-Gasket No. 3 harden?
No. The sheet says it changes to a pliable, tacky film through solvent evaporation. It gives 4 hours to operational and 24 hours to full cure.
How long does this product take to fully cure?
Permatex states: The data sheet says full cure is effective after 24 hours. Conditions: Dry times vary with temperature, humidity and gap.. These are the manufacturer’s stated times, not a guarantee.
What affects how long this product takes to dry or cure?
Times depend on temperature, humidity, film or bead thickness and airflow. Follow the current data sheet and label. Follow the product label for your conditions.