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Don Duden Using Cyanoacrylate for an outside finish: I first started experimenting with Cyanoacrylates in early 1993 with good results. Yes, if you do a good job of application and sanding, you can use it for a final finish. It will finish like a glass and hold up to almost anything. However, you do lose some of the patina of the wood, the soft touch. I have overcome this by adding a least one coat of deft. This gives the wood a more waxy feel and if you haven't done a perfect job, you need a final coat anyway. The application: Be careful! It will get all over you or go on very rough and requires a lot of sanding. However, it will sand easily and make a white dust. It will not gum up sandpaper. I have used a dozen different applicators in my experimentation, including small brushes, several varieties of foam, various paper products, plastics, acrylics, cotton, and just rubber gloves. I have probably applied 200 bottles at this point and find heavy duty shop paper towels folded into small pads to be the best. The best foam is that which is used to make round factory-ready covers for your pipes (water not smoking) to keep them from freezing. The rubber gloves work if you are reasonably fast and don't apply too much with one glove. Wood reactions: Light woods and very soft woods will streak, never-to-be-corrected if you allow a run or move too slowly. Use a sweeping stroke and keep moving. I've found the Medium thickness Cyanoacrylate to be the overall best. However, others are good depending upon the wood. If your surface is very rough, the Thick is best because of its filling capabilities, or if the wood is extremely hard, well finished, and medium to dark in color, the Thin will work well. The sanding: I use 220 grit for general sanding, then finish with 320, 400, 600, and 0000 steel wool. Be careful not to sand through your finish because a final coat of lacquer of other finish may soak into the wood and you will have a dull spot. Should you sand through, just add another coat of cyanoacrylate to the area. The accelerator: Most people tend to spray too much CA Activator when patching cracks and that causes a white coating or foaming to appear in the glue. When patching, this can be a real problem because it is so hard, if not impossible to remove. Go light with the spray. Generally a light touch will harden in 20 seconds or less. Aerosol Activator misting action is probably a better choice than pump spray to alleviate this problem. If you are finishing a flat surface and get "whiting" it will easily sand off. However, if you don't need to use and accelerator for a real purpose such as building several coats in a deep crack it's probably best to avoid it when using the glue for general finishing. The accelerator will create a micro moon surface hard to see until you begin to sand. The more your glue finish hardens, the easier it is to sand. Side Benefits or other values: If your wood is weak, very thin, or cracked, the glue finish will "Lock it up." It adds a lot of strength to the wood. If the wood is soft and a fingernail can mark it, this finish will reduce that possibility to almost zero. If you have a lot of cracks, you can keep working the glue finish until you have eliminated them all. You can still see the crack mark or color but the finish is perfect. Fill your large cracks in with a mixture of sanding dust and either the medium or thick glue. This gives strength and color. I keep small bottles of a variety of wood dust just or "coloring" the filler and can now match almost any color of wood. If your wood is in good shape and you use traditional finishes except you have one bad spot of punky wood, the glue will come to your aid on that spot. You can also apply it over many finishes if you find a bad spot after your first traditional coat. If you do this, always go back with a final coat of finish. For natural edge pieces, use the Thin glue to preserve the bark. It will give the bark strength and keep it from separating from the sap wood. |