Re: not for chisels
ThomD
>As a general principle, one doesn't tap out chisels. Just plane/wide blades. Odate says this about taping out chisels "Unless chisels are over 2" wide their flats are not usualy taped out". For one thing, consider that a 3/8" chisel can have the same profile as a plane blade almost 3" wide. What is the chance of deflecting the 8 x narrower chisel. Think also of multi hollow backs.
As Pam's experience points out, any time one thinks it will work I suppose one can give it a wack and see what happens. Be aware of the shape of the hardened metal in your blade it has deep section, and narrow sections. Taping out depends on deflecting both the iron and the hardened steel. So wack away, but be aware of what you are trying to deflect if it is an area with a deep rib (say the sides of some chisels where they are wrapped up) you are asking for nothing to happen, or a crack.
I have tapped out plane blades and It takes some force, certainly nothing like sinking a 16d, but one is deflecting metal, the wacking leaves marks on the blade. You don't need a anvil, but you do need a means of supporting the blade just a little behind where you are hitting. Odate is pictured using the beveled edge of a post, I have the "proper" anvil which is in fact made out of railway track, or was made in that shape. One end has a bevel on it so that one can hold the blade on it at an appropriate clearance angle.
You only get experience of this stuff by doing it. Unless you can't hit a mark with a hammer I don't see the harm in trying. Do not hit the hard steel, hit about midway on the bevel. The blade may crack, but that can happen even to experienced people. The impact position is with the near edge of your hammer hitting the middle of the bevel, leaves little smile marks.