How to bond fiberglass
How to bond fiberglass (also known as GRP or glass reinforced plastic)?
This is a composite material with extremely high structural strength making it popular for high impact or highly stressed applications.
It is lightweight, and there is a strong requirement for adhesives
to bond fiberglass as it cannot be welded and mechanical fasteners
not only add to component weight, rattling, and vibration loosening but can affect the structural integrity of the material if it has to be drilled.
- Bath tubs
- Hot tubes
1. Degrease with Permabond Cleaner A or isopropanol (do not use meths or white spirits as this can leave a residue).
2. Lightly abrade by one of the following methods
-Wet and dry grit paper (carborundum paper) 320 grade recommended.
-Red Scotchbrite pad
3. Degrease again to remove any contamination or loose particles.
It is OK to bond as received but if you wish to have a consistent bonding surface and better mechanical keying of the adhesive then it is recommended to carry out this surface preparation.
What is the best adhesive to bond fiberglass?
Several types of adhesives bond well. Understanding the desired cure process as well as what the bond will need to endure will help us choose the best adhesive for each carbon fiber application.
Cyanoacrylate – also known as instant adhesives, super glue, crazy glue, ca glue, etc. For bonding carbon fiber reinforced polymer consider a black, toughened grade such as 735 low viscosity or 737 medium viscosity. For clear bonds consider Permabond 731.
Two component epoxies – Permabond two part epoxies cure at room temperature and provide strong bonds to fiberglass.
Structural acrylics – MMA grades such as TA4246 are very strong carbon fiber bonders.
Polyurethane adhesives – All Permabond polyurethane adhesives offer high strength, high peel strength, and good impact resistance.
With so many choices of adhesives to bond carbon fiber, the desired cure process, the desired environmental resistance, and the desired temperature resistance are key factors in choosing the best adhesive for each application.