Part Four: Epoxy and Varnish
Epoxy as a wood coating has volumes of writing about applications and pitfalls. Getting a reasonable temperature to work in is the challenge. Heat of the summer and the coating dries really fast. Cold, below 55 degrees, and curing can take days.
First Epoxy the EMT: The EMT is the first time to get epoxy. The tubing is hollow so it needs to have a washer for the insertion Sanding between coats is nice and avoiding drips is the goal. With all that said, I just want to get 3-4 coats of epoxy down, as few sags as possible and sand once-twice to smooth out before the varnish coat. My wooden kayaks are entirely different. I carefully sanded and assured all was as sag free as possible. The fish are an outdoor installation that will see lots of conditions. So, a few sags does not offend my sense of perfection.
I crafted simple stands to assist in the epoxy and varnish stages. A pine 4X4, dado blade on the table saw, cut a depth around 2" and the width of a 2X4 and I have a base. The EMT is inserted into the underside of the shape. The tube is hollow so a washer needs to seal the EMT from the epoxy. I have found that a .05 cent coin is the perfect size for the washer. After lots of time in the big box hardware section and lots of leftover washers I found the solution. I was paying .13 cents for an imperfect fit that I taped to end of the EMT to insert in the shape. That worked. BUT, the nickel is the perfect friction fit. Tap in the nickel into the EMT, rough up the OD of the EMT with a file/60 grit sandpaper, prep some epoxy, coat the hole with epoxy and insert the EMT. If you have extra epoxy from the batch, coat the shape with the what is left.
From the material that I have read pennies are considered lucky and added to the weathervane. The number may represent the people in your family, dates of birth on the coins, number of cars? Or maybe just a weight to balance the weathervane. So, the nickel is not out there too far. When installing, I used a rat-tail file to ream/reduce the ridge/burr created by the tube cutter. Once that is done, the installation is tight. The nickel at the top of the tube will rest against the top ( or bottom depending on your view of the world ) of the forstner hole. That and it will have epoxy sealing around it. In the final installation, a single bearing will be inserted in the EMT tube, on top of the rebar. The result will be the bearing inside the EMT, between the nickel and the rebar. That gives the bearing a tight pivot point that is solid -- metal nickel, bearing and rebar. It works well and should last indefinitely. Add occasional lube, grease and the system is maintenance free.
Try and have the EMT level and plumb. When the epoxy sets, you are ready for the first coat of epoxy. Here are the re-purposed redwood shapes, EMT mounted on bases for easier epoxy and varnish application, indoors. The base for each allows for the shape to pivot in the wood base/EMT connection. No fins yet. Just the drilled hole for the EMT in the underside. The slots for the fins will be added after the epoxy and varnish are dry, cured and complete. Epoxy and varnish drip. I have paper rolled and cut below to catch the drips and assure domestic semi-tranquility.
Coat the Shape in Epoxy: The bases work for a solid support while coating with epoxy and varnish. In the past I suspended the shapes from the chandelier over the dining table for days while I was coating. Not the best move for household harmony. BUT, the temperature was controlled and it worked. I moved to larger shapes and the chandelier was going to have too much weight and household harmony too much at risk so I needed a solution.
The photo shows the 4X4 mounted on the 2X4s, drilled for the EMT to be inserted. I will probably drill a matching hole for the rebar to allow a bench/table top installation. Not ideal, but for some purposes just fine.
By now you have the idea that this is a bit of a project. It is. With the epoxy and varnish steps complete -- and that can take days with a 24 cure/dry cycle for epoxy/varnish/ sanding and coating -- you can begin to consider the Finishing. The application of the fins, shape, size and shape of the fins.
Part Five: Adding Fins
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