Planishing hammers have their place in auto body shops and the garages of serious hobbyists and do-it-yourselfers. Planishing is traditionally the hand done technique of flattening sheet metal using a planishing stake while the metal is struck by a planishing hammer to flatten out the small dents and undulations left behind after more extensive metal smoothing techniques such as “sinking” and “raising”. This makes work with the planishing hammer much different from other hammers such as framing or riveting hammers.
Before, planishing was done with the using of ball-pein or neck hammers. These hammers usually have polished surfaces and rounded edges that prevent the metal from being marred and distorted. Rubber mallets and rawhide mallets were also used to flatten out sheet metal. Using these soft headed hammers, planishing was less-mistake prone but also lacked the ability to flatten out wide imperfections across the metal. These planishing techniques are still used today and are quite effective, although they are very time and energy intensive pursuits.
These days the more commonly used planishing tools are the pneumatic planishing hammers. Made in the vein of pneumatic hammers, these planishing tools use air to provide power for the flattening strikes on the sheet metal. These are automated and electrically powered planishing tools such as the ones made by Eckold Tools and Grizzly Professional Planishing. For large scale and professional work, there are shop sized pneumatic planishing hammer tools such as Grizzily’s GO497 model. This model is measured at 62 inches in height by 31 inches in width and 34 ½ inches in length. It can deliver up to 4,600 blows per minute from 15-20 pounds per sq. inch of air. It can shape steel up to a 16 gauge thickness. This model is priced at 695 dollars.
For smaller scale jobs, a hand held pneumatic planishing hammer may be more suited for do-it-yourselfers and hobbyists. One such tools is the G2 model Planishing Hammer Kit from Eckold Tools. This planishing kit used a hand held planishing hammer that uses a 36 pound per square inch pressure for its “air hammer”. It has 5 steel inserts for the head and 5 synthetic inserts designed to prevent marring softer metals. It also has a 12 degree swivel adapter for planishing work on edges and corners. This kit also has 3 black synthetic inserts that may be shaped according to individual needs and a DVD on “Hammerforming” techniques. The entire kit is priced at 2,195 dollars.
Whether to use manual or pneumatic planishing is entirely dependent on preference. Manual planishing hammers are practical for small scale and irregular users. These offer good results for a low price. For professionals and regular users, pneumatic planishing hammers are a good option, with consideration for the type of work and resources available.