Blacksmith Artists in the Southeast Georgia Region
How to Protect Your Ironwork
By Doug Bracken
What are the traditional options for finishing fine metalwork?
What follows are the six most common formulas for the wax or oil or wax/oil finish ingredients and methods for application. There are of course many others, some of them more mystical or dangerous, but the foundation for good oil/wax finishes is below.
To a clean, wire brushed piece of forged (properly textured) iron apply the following:
1. Raw beeswax is directly applied to warm iron (almost too hot to touch with one’s bare hand) and allowed to melt and penetrate the surface of the metal. After sufficient applications to form a protective coating, use an emery cloth to highlight the metal surface, then polish it with a rag. Last, apply one more layer of wax at room temperature, and buff the surface with a lint-free rag. It is important to keep the iron at a warm temperature to allow the wax or wax-oil to penetrate the pores of the metal, but allow it to burn. Since this is a natural material, this finish, like mineral oil, would be suitable for eating utensils.
As with all of the following waxes and oils, heat caramelizes the wax or oils and gives a rich black bronze color to the surface of the metal; using an even heat is important to achieving a consistent color from section to section. Different waxes and oils create different colors as they caramelize, and so experience in juggling all of the variables above is key to identifying your preferred final color.
2. Substitute commercially available Butchers Wax or Johnson’s Paste Wax or color tinted Briwax (or similar) for the above using the same application method. These waxes have additional ingredients that promote faster drying and a harder finish when they dry. Because they have solvents and other compounds that make them more resilient, these are not suitable for eating utensils. Once the emery cloth has highlighted the metalwork, the final coat of clear wax should be applied cold and buffed to a nice luster.
3. Follow the same steps as above, but substitute raw or boiled linseed oil for beeswax and use after the oil dries (raw linseed oil has no dryers – it will be sticky for days or weeks as it dries, depending on humidity and ambient air temperature). After burnishing the hot oil finish using emery cloth, apply a clear wax at room temperature and buff.
4. Substitute tung oil for the linseed oil. I have met several smiths who feel that this finish has enough penetrating properties that it can also be used cold. After burnishing, apply a clear wax at room temperature and buff.
5. Create a proprietary or unique mixture of wax and linseed (raw or boiled) or tung oil using turpentine as a thinner, and apply it in the same manner as 1, 2, 3 and 4 above. The formula I have seen most variations on is: 1 cup beeswax or Johnson’s Paste Wax, 1 cup turpentine and 1 cup linseed oil and 1 tablespoon of Japan dryer. The turpentine thins the mixture to allow for better penetration, and the Japan dryer promotes faster drying of the linseed oil. This oil/wax finish is burnished, and a final coat of clear wax is applied cold and buffed.
6. Add colored waxes or dyes to stain the solution, or waxes or wax-oil mixtures above (usually a brown or black tone).
The result is a rich, lustrous, colorful and semi-transparent finish that highlights the character and elegance of the metal starting at the very surface of the material. The materials are not expensive, but the process to apply them is fairly labor-intensive so this will be the driving factor in the cost associated with this work. As with any craft skill, the best results are achieved through experience and patience.
In an air-conditioned environment, this type of finish will last for years with little or no maintenance. It is recommended that the metalwork be waxed as often as fine furniture, but this may be excessive in many cases. If a spot of rust develops, simply rub it out with emery cloth and apply a coat of clear wax. Then wax as needed to maintain the finish. If the work at hand is exterior and not exposed to a lot of weather, the finish will perform well there too, but use caution or expect more regular maintenance of the metalwork if it is exposed to weather.
To realize your ideal finish, insist on samples which show some of the typical joinery using actual materials as they will be executed. The larger the better, as almost anyone can finish a small stick of material. The proof is in a full-scale mock-up.
Caution: For those inclined to try this at home, care must be taken to avoid exposure to burning oil and wax fumes. Some oils and waxes contain volatile compounds that are harmful when inhaled, even when cold. Additionally, mixing oils and waxes requires the creation of a very flammable hot liquid, so it must be done without an open flame – over a double boiler, for example.
For the full article follow this link: http://www.traditionalproductreports.com/ornamental-metalwork-finishing.html