CARE and MAINTENANCE of a NEW or OLD ANVIL
Older anvils can be found with many problems associated with poor care and maintenance. Some of these problems include: electric welding slag or residue on the face of the anvil, cuts in the face from using a torch or angle grinder, broken horns, chipped edges, broken or loose face plates, rust or pits in the face plate, along with many other problems. Many of those problems could have been prevented with proper care and maintenance:
An anvil like any hardened steel tool when struck with another hardened steel tool such as a hammer can produce broken off pieces of extremely sharp metal which can fly through the air at velocities high enough to be extremely dangerous. Always work safely when around hardened steel tools.
1. It is not prudent to hit the face of an anvil directly with a hammer. This is particularly important regarding anvil edges and the tips of horns. The goal is to keep hot iron between the anvil and your hammer.
2. As errant hammer blows do happen, use hammers that are softer than the face of your anvil. The harder the anvil, the easier it is to find softer hammers.
3. When an anvil is cold, it helps to warm it before using. Cold anvils are more susceptible to breakage when struck. When an anvil can not be kept in a warm room, warm the cold anvil by laying on pieces of hot iron, hot irons normally used for ironing clothes, heat lamps, electric blankets, electric heating pads, or anything that will warm it up. Keep in mind that it takes a long time to warm up a cold anvil. Also, keep in mind that the overall anvil should not be heated over approx. 250 degrees Fahrenheit as higher temperatures could draw the hardness from the face.
4. Subjecting the small ends and/or fine tips of horns to heavy hammer blows is not good for the anvil. These areas of small mass are more susceptible to breaking, bending, and/or mushrooming.
5. A general rule is not to use a hammer or sledge any heavier than 1/30 of the weight of the anvil. Sometimes purveyors of blacksmithing information use 1/50 rather than 1/30. If the 1/30 rule is used a 150 lb. anvil could have a maximum hammer of 5 lb., and a 300 lb. anvil could be used with a maximum hammer/sledge of 10 lb. With the 1/50 rule those maximum hammers are 3 lb. and 6 lb. respectively. Remember that the safest place to use heavy hammers/sledges is at the anvil’s “sweet spot” which is the center of the face over the main mass of the anvil. When using a sledge over the horns, strike over the thicker portions of the horns.
6. Refflinghaus and other anvil manufacturers chamfer a new anvil's edges at the factory. If a new anvil comes with very square sharp edges they should be chamfered or rounded at least a little. This softening of the edges includes the hardy hole and possibly the pritchell hole. Anvil edge softening is always a compromise. The sharper the edge, the more susceptible the edge is to chipping. The bigger the softening/chamfering the less it may chip, but the less useful it can be for some of the more delicate forging operations where a square corner/edge would be preferred. Generally, the harder the anvil face and/or the heavier the anvil, the bigger should be the edge radius or chamfer. That is assuming that a heavier anvil will receive harder hammer blows with heavier hammers/sledges. See good article: http://www.anvilfire.com/FAQs/select_faq_index.htm.
7. For some forging and bending operations a small and short rounded edge on the anvil is very useful. This rounded edge is generally found on all old anvils. Both sides of an anvil face usually have a small (2 1/2 to 4 inches) portion of the anvils edges that are rounded. The reason for “small” is to preserve as much of the square edges as possible. The smaller the anvil, the shorter this rounding should be as there are less square edges on a smaller anvil. The heavier the anvil the more could be the radius, but with a new anvil start with the largest radius being no more than approx. 3/32 inch. That would be the roundness of a 3/16” drill bit maximum. The rounded edge can always be made a little bigger, if needed, but not smaller. My anvil has the roundness of a 1/4" drill bit and 4" long on my 330 lb. anvil.
The typical older anvil face would have this larger radius rounding start at the round horn and gradually decreasing/tapering to a square edge back about 1/3 of the length of the anvil face. That would leave about 2/3 of the anvil with the anvil’s sharper edges.
Today the trend with blacksmiths is to not taper this round edge 1/3 of the anvil face like was typical in the past. The current reasoning is that bending wider stock on a taper is generally not as good as when bending on an edge that does not taper. Also, limiting the length of the round edge preserves more of the anvil's square edge. Therefore, an even 3/32” radius about 2 1/2 to 4 inches long seems to be the current preferred method.
The weakest parts of any anvil are it's edges. With use and time all anvils suffer from edge damage of some kind, therefore everything possible should be done to preserve the square edges.
8. If a used anvil has enough of a square edge to be adequate, then any edge chips should just be minimally ground to a smooth radius and used as a forging die. Electric Welding to repair an anvil edge is not recommended until an anvil no longer has an adequate square corner. Welding on the heat treated face plate always takes the heat treatment out of the area next to the welding, and the only way to get that area hard again is to heat treat the whole face of the anvil. Heat treating an anvil in the home shop is usually not practical.
9. For centuries, the accepted or at times the only practical way to make hardy tools has been to forge the shank of the hardy tool to fit the hardy hole and to then to forge the bottom of the tool with the shank in the hardy hole. This helped insure a good fit and flat bottom on the hardy tool. This method has the potential for drawing the hardness out of the steel around the hardy hole, but this is still the accepted method. This is the method that I use. It has not had a noticeable effect on the steel around the hardy hole, probably due to the mass of steel in the anvil drawing the heat away from the hardy hole.
10. Most anvils rust when in contact with dampness or water. Wax, WD40, or similar products help keep the surface smooth and rust free. Objects left on an anvil face can result in condensation between the anvil and the object during periods of high humidity and temperature changes. It is best not to store items on the anvil. That said, an anvil that is not too slick and shiny is by far more useful. Therefore an anvil with a patina and/or mild rust is better than a shiny faced anvil.
11. Anvils with very smooth faces can be marred by bolsters and hardy tools if they are not smooth on the bottom or if they have slag under them. This can happen to even hard anvil faces, but not to the same degree as when the anvil face is soft. Most blacksmiths probably do not worry about this as it is a typical use of the anvil, but if you anvil is new or especially smooth it is something to consider if you want to keep it that way.
12. Damage such as nicks, sway backs, pounded down edges, chips, breaks, etc. happen to an anvil face only when cold steel hits or abrades the anvil face. Hot iron alone typically does not cause damage as it is soft.