Hello. Newb here..
I have been slowly putting together a basic set of mortise chisels and opting for the advice of Mr Smalser have thus purchased these three. The thinnest with light colored handle and the middle on in the attached images are witherby ( winsted edge tool works) 1/4 and 1/2 inch respectively. The thickest of the three is a 3/8 inch beast which has no hooped handle but is a massively thick chisel. purchased from our favorite auction site. Its a W.Greaves and is a very old chisel.
Of the three the 1/4 incher is most charachteristically an old millwright mortise chisel. The 1/2 seems to fall in line as well. But that 3/8 is an odd one. I wonder if it could have been intended for slightly different use originally??
also of these the 1/2 inch has a nice flat back running nearly the length of the whole blade. The 1/4 incher curves up slightly near the edge giving a slighlty crowned back and the 3/8 is crowned so bad I am having a hard time determining a good way to flatten it. You can see how bad it is in the picture . I slapped some 60 grit down on my granite surface plate and it laughed at me after 15 minutes of feverish lapping.
Howw do these chisels get such a convex back? and how flat should the back be on a mortise chisel ? Seems like pretty flat to me so as to give me a straight sided mortise? Ergo Does anyone know of a good way to hasten the flattening of such a heavy chisel.. I have a Baldor 6 inch high speed with norton cool white wheel on it. I have considered maybe using it but I am not so sure. Belt sander?? Anything else I should consider?
Thanks.
Joel.