Corneel":2i66iyc9 said:
....... it looked like the chisel had a single bevel all the way of 35 degrees, instead of something like 20 degrees with a 35 degree secondairy bevel.......
He does single rounded bevel sharpening. Very sensible! Not many people realise that the obsession with two bevels, "micro" bevels etc, is a relatively recent fashion.
He certainly looks effective with his bevel edge chisel.
But I'm a bit doubtful about his OBM technique.
I was taught to do it quite differently:
1 First and most obvious is to use a big mallet - the biggest you can handle.
2 Hold the chisel
vertically with every single cut - no levering at all except when it comes to cleaning out the bottom of a blind mortice. Waste is levered out as a final operation, with a smaller chisel same as Sellers demo. - Through mortices don't need this, the waste just gets pushed through.
3 Work it in the direction of the flat face - opposite to Sellers.
I'm sure it is faster (helped by the big mallet) but it also has another big advantage - you can do your mortice flat on a bench top (if it's low enough) or on a mortice stool (cf Ellis) without the need of holding devices or a vice. This is because the cut is always vertically downwards, no tendency to push the workpiece in any other direction.
In fact you couldn't exert maximum bash with big mallet on something being held as the holding device would leave marks.
I'll stick with this as far as OBMs are concerned but 'll certainly have a go with a bevel edge next time I'm at it.
PS bench height - a normal bench is a bit high for morticing. Mine is adjustable - I just insert/remove blocks under the legs as necessary. An alternative is a little step up - just a piece of ply on blocks.
Matthew's worry about warranty - you wouldn't want to bash one of those pricey fashion-statement chisels with a big mallet, which is another good reason for not buying them!