|© Robb Gunther and Karl Schuler
The Forgery School of Blacksmithing
published in ANVIL Magazine, April 1998
This process works well on wrought iron base anvils and cast iron base anvils with a good tool steel top. It was developed with the help of several metallurgists and welding engineers at Sandia National Laboratories.
Grind all surfaces to be welded.
Preheat a wrought iron base anvil to 400 degrees and a cast iron base anvil to 450 degrees. The temperature can be verified with a Tempil Stick crayon available at Your welding supply store, which melts at a given temperature. (i.e., 350 degrees, 400 degrees, 450 degrees. A propane-fired weed burner works well to preheat the anvil. A wood fire call also be used if care is taken to wire brush off all carbon and smoke deposits before welding. Be careful to not overheat the anvil, particularly the heel and hardy hole area, as it's a thinner cross-section and heats faster than the more massive parts.
What You'll Need
When welding to a cast iron base anvil and on to the cast iron base, a layer of NI rod (high nickel) must be Put down first. Build Lip over the NI rod with Stoody 2110 (or equal); Unlimited passes (DC reverse); expect 45 Rockwell as welded. The last three passes (or layers thick), use Stoody 1105 (or equal) 1/8" rod (DC reverse); expect 50 to 52 Rockwell C as welded if you don't exceed three passes thick.
Cast steel anvils repair well using the combination of the Stoody 2110 and the Stoody 1105 (last three passes).
Repair to the Horn
If the area around the hardy hole or pritchel hole needs repair, weld using the above detailed process; however, inserting a chill (or form) made of 1/16" sheet copper into the respective hole before welding will save you a lot of grinding and filing to true up the hole.
These hard surfacing rods used here to repair anvils are quite gravity sensitive during the welding process. If you can lean the anvil at 445 degrees against a cinder block while welding on the edges, you will have more of the somewhat expensive welding rod on the anvil and less on the floor.
After all welding repair is complete and you are sure that there is sufficient buildup to allow for grinding to the desired finish (check with a straightedge), post heat back to 400 degrees or verify with the Tempil Stick that the anvil is still that hot from welding. Pack the anvil in vermiculite (crushed mica), available at most nurseries, to allow it to slow cool for a minimum of eight hours. This will minimize the potential for stress cracking from welding.
Obtaining the Desired Finish
This anvil restoration process has been used on several hundred anvils around the country with great success.