FC-8 Lightweight Bonding Putty

FC-8 Light Weight Bonding Putty


Are you looking for a strong, waterproof, lightweight bond? Our FC-8 Bonding Putty provides you a lightweight, flexible bond with high tensile and flexural strength. Great for areas that need weight reduction like T-Tops, sandwich bonds and cap to hull adhesion. Offered in multiple sizes.


*For Drum Quantities – please contact us via our Contact Us page.


FC8 Bonding Putty


FC8 Lightweight Bonding Putty by FGCI is a strong, lightweight, easy to use putty that is very thick, easily spreadable and is great for everything from boat building, automotive applications, parts production and so much more. FC8 is Polyester based, so it uses MEK-P catalyst, and can be applied to surfaces like:

  1. Polyester Laminates
  2. Vinylester laminates
  3. Wood
  4. Metal
  5. Gelcoat

FC8 has a gel time of around 20-25 minutes at room temperature, sets up in around 1-3 hours and fully cures in around 24 hours.

PLEASE NOTE: This information is provided in good faith and correct to the best of our knowledge. No warranty, guarantee, or representation is made as to the sufficiency of the information for the safe use of the product, nor to relieve the end user of any Federal, State, or Local regulatory responsibility.

Catalyst Concentration Chart - Resins and Gelcoat

Surface must be clean and dry. Roughen with coarse sandpaper for best adhesion. Remove any paint, rust, or scale.

Add 2% MEK-P by weight and mix thoroughly. Smooth on putty working well into pores.

Where holes go all the way through, extend putty beyond the damaged area for greater strength.


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    “Been working on a skiff project and using all FGCI products. They came highly recommended by my friends who are boat builders. It is the highest quality resins, glass, and gelcoat for the money. They made it really easy for a newer person to boat building. The customer service is phenomenal and they are always knowledgeable and ready to help with any questions I had.”