Product comparison
Bostik 940A vs 940A FS: Which Fits Your Marine Job?
Both products are Bostik SMP marine adhesive sealants. The main choice is how much time the installer needs to position, assemble and tool the joint. Bostik describes 940A as the longer open-time option and 940A FS as the faster-setting option. The right choice still depends on the joint, materials, conditions and work sequence.
Choose 940A when working time matters
Bostik 940A gives the installer a longer working window. Consider it for larger or detailed joints, assemblies that take time to position, and jobs with several steps before final tooling.
In Iris’s Florida experience, the standard version is often the more practical starting point when warm conditions make a short working window difficult. Confirm the actual handling requirements for the job.
Choose 940A FS when faster progress matters
Bostik 940A FS has a faster skinning and setting profile. Consider it when the work sequence benefits from faster progress and the crew can position and tool the joint within a shorter working window.
Fast Set is not automatically the better choice: a rushed or complex installation may need more working time.
What should you check before choosing?
- Both substrates
- Joint size and design
- Bonding versus sealing
- Exposure
- Installation conditions
- Time needed to position and tool
- Need for earlier handling
- Desired color
If the materials or preparation system are uncertain, ask Iris to review the application before selecting a product. See also general marine bonding & sealing.
Common questions
Is Fast Set stronger or better for every marine job?
No. The faster profile addresses a work-sequence need. Product selection also depends on the joint and materials. Do not treat speed alone as proof of better suitability.
Can either product be used for window perimeter sealing?
Both appear among Iris’s options for marine window perimeter work, but suitability depends on the glazing, surrounding material, joint design, exposure and preparation. Send Iris the window details for review. Neither product is a universal window adhesive.
What about fiberglass or aluminum?
Identify the material on both sides of the joint, any coatings and the service conditions. Iris can check the relevant Bostik guidance and preparation system for that specific assembly.
Where can I get current working and cure information?
Request the current technical documentation from Iris. There is no universal handling or cure time, because conditions and the specific installation matter.
Not sure which one fits?
Tell Iris what you are bonding or sealing, how much time the installation takes, and whether faster progress is essential. Our team will help narrow the appropriate Bostik option.