Marine Varnish needs a good base or it will crack and fade. Here’s how to make a great base for your next marine varnish project.
Review of WEST SYSTEM(R) Epoxy Resin and 207 Hardener
We were given this lovely old Oregon spar which looked a bit tired and neglected. Instead of being coated with an appropriate marine varnish, it had been painted. The spar is apparently well over 100 years old and has been out in the weather for most of that time.
Like anything to do with wooden boats it certainly needed some TLC.
This spar will return to being out in the sun and salt air. So we wanted a product known for its toughness and weather resistance as a base for our marine varnish.
If you only use marine varnish as a coating, it faces two problems. Firstly the substrate expands and shrinks forcing the varnish to stretch and shrink to remain attached.
The second issue is the oxidation from exposure to the sun’s UV light, which reduces gloss and causes cracking.
Product:
We used WEST SYSTEM Epoxy Resin 105 and 207 Hardener. While not marketed as a marine varnish, this product combination has a reputation for producing a tough and lasting plastic bond. It is widely used for new builds and repairs on many boats, including wooden boats.
It makes a great base for a final coat of marine varnish.
Product Description – excerpt from https://www.westsystem.com.au/product-category/epoxy-resin-and-hardeners/
105 Resin
WEST SYSTEM 105 Resin is a low viscosity, solvent free liquid marine epoxy resin. Formulated for use with WEST SYSTEM hardeners, it can be cured in a wide temperature range to form a high-strength solid with excellent moisture resistance. 105 is designed specifically to wet -out and bond with wood-fiber, fiberglass, reinforcing fabrics and a variety of metals when mixed at the correct ratio with a WEST SYSTEM hardener. An excellent epoxy adhesive, 105 mixtures will bridge gaps and fill voids when modified with WEST SYSTEM fillers and can be sanded and shaped when cured. With roller applications, it has excellent thin-film characteristics to flow out and self-level.
207 Special Clear Hardener
WEST SYSTEM 207 Special Clear Hardener has been specially developed for coating applications where a moisture resistant, natural wood finish is desired. 105/207 mixtures resist clouding in humid conditions and exhibit extremely low blush formation – as low as any epoxy, including so-called “no-blush” epoxies. 105/207 has strong physical properties, so it can be used as a structural adhesive for glueing and laminating. It has excellent compatibility with paints and provides a beautiful, long lasting finish when used with quality UV-filtering varnish.
The Epoxy Resin can be combined with the hardener which suits your application.
Method:
First the spar needed a good sanding. We started with 80 grit then 150 and finally 220 grit for a smooth finish.
Then Craig the furniture maker applied four coats of the 105 and 207 mixture.
Note: Mix according to manufacturers’ instructions. If you are new to this product, it’s worth taking a little time to read the instructions and prepare accordingly. The results will show that it is time well spent.
Result: The spar hasn’t looked that good for a long time and with a few coats of marine varnish to provide extra UV protection, should be good for another 100 – well, many more years.
What we liked about this product:
The finished product is tough and looks great. It provides an ideal base for the final coats of marine varnish.
Be careful of:
Check the temperature before using this product.
Mix well – follow the instructions carefully.
Comments from some of our Facebook group members:
“Best epoxy in the world.” Marintechnik Nord, Germany
“Industry standard. It’s the main ingredient to any fiberglass boat renovation or building. I used it with roving cloth to reconstruct and replace my transom on my 1965 fiberglass Bertram. ” Dominic Fontaine, Captaining for 28 years and holds 200 ton lic. Maine, USA
“World standard epoxy resin and associated products“. Chris Morris, Marine Industry Professional, Tasmania
