Professionals and Amateurs Together

Resorcinol vs Epoxy Glue

Question

What are the differences in the use of resorcinol and epoxy glue for boat or outdoor uses?—John Watson

Answer

Steve Costain replies: I used resorcinol years ago to build some outdoor screen panels, but today I would use West Systems for any outside purpose. I recently bought a tiny scale to measure small lots of epoxy when the pumps create too much volume and waste. It came as a kit with the scale, a couple squeeze bottles, mixing cups and stirrers for about $40. I use epoxy more often now that I can mix small batches.

I would suggest that you get familiar with the thickeners that West System sells, epoxy can be thickened to the consistency of peanut butter and won’t drip—www.westsystem.com.

Jon Siegel replies: I have not used all the variations of these products, but here are some observations based on my experience:

Both are waterproof and weatherproof and both have to be mixed immediately before use.

Resorcinol—Mixed from powder and liquid resin. It is waterproof and non-flexible. Do not breathe the powder as it contains formaldehyde. It sets overnight. Wet cleanup is with water. It withstands direct sunlight. It dulls blades quickly. It has an open time of 30–40 min. It is dark brown in color.

Epoxy—Mixed from two viscous liquids. It is waterproof and somewhat flexible. Do not breathe the ammonia fumes given off. It sets overnight. Wet cleanup is with acetone. Keep painted or covered from direct sunlight. It is kind to blades. Open time depends on mixture. It is clear in color.

Tags: Epoxy, Finishing