chisel and gouge sharpening angles

[Kel-Kat]

I just received a couple of large gouges and a corner chisel.
All are in need of sharpening.  Wondering what angles to sharpen them at for timber framing.  Some oak but mostly softwoods.   Any tips greatly appreciated.

Thanks, Scott

[Jim_Rogers]

Scott:
Hardwood has one set of angles and softwood has another. Usually framers working in both have two sets of chisels one for each to avoid having to change angles when sharpening.

My book on sharpening says:

15° to 20° for Paring chisels, skew chisels, low angle planes for softwood, skew-blade planes.
20° to 25° for All of the above (except skews) for hardwood or end-grain use.
25° to 30° for Chisels used both for paring and light mortising, firmer chisels for softwood, most plane blades and spokeshave blades.
30° to 35° for Mortise chisels, firmer chisels for hardwood, plane blades for hardwood with pin knots.
35° to 40° for Mortise chisels for heavy use, particularly and with brittle steel.

I many use only softwood so I think mine are set at 25°


Hope this helps.

Jim Rogers

[Raphael]

I have two ~1.5" chisels I use most, the house project combines hard and soft woods heavy on EWP:

  My old P.S.&W. is a bit over 1.5" and is hollow ground at 25º, the secondary bevel starts at 25º and slowly creeps up in angle until I regrind it (~27.5º).  It's good for paring harder wood and endgrain but it's generally used in soft wood mortices.

  My extra long Sorby is registered to a perfect 1.5" so it's ideal for 1.5" mortices (chisel and mortice checker all in one), it is hollow ground at 27.5º and I'll let the secondary bevel creep up above 30º before regrinding as it's used mainly in hardwoods.  This could stand to start out steeper but it works fairly well for the assortment of timbers I'm working with.

  My hollow grinding is done on a water cooled stone so I need not worry about burning the steel.  Secondary bevels are established and maintained on a lapping table with abrasive film (google "Scary Sharp") and field dressing is done on a soft arkansas stone.

  I've got corner chisels, they are a bit more tedious to maintain and they wear on the corners of my grinding wheel so I don't pull them out very often (more likely in a 1.5" mortice).  These are sharpened at a good 30º-35º as they usually get a good pounding.  I'll field dress these with an old carborundum stone, a $2 tag sale find that is still flat and has 90º corners.