[TheForge] While we're spring cleaning - chisel handles

[Andrew Vida]

On 2/15/2013 10:51 PM, Craig Schaefer wrote:
> While I was cleaning out a toolbox, I ran across a socket chisel with
> no handle.   Looked around the shop and found a suitable piece of
> zebra wood and fashioned rough handle. How are the wood handles and
> chisel sockets supposed to be held together?

There are three methods for fixingwooden handles to chisels of which I 
am familiar.  The most common is the tapered tang and shoulder.  Drill 
an appropriately sized hole in the wood and drive the handle onto the 
tapered tang until it seats against the shoulder.  Such handles should 
always be ferruled to prevent splitting.

The other way is the pure socket where the taper of the chisel is 
comparatively long with a low angle.  I do not know whether they are 
retained in the same basic way as metal tapers where a non-releasing 
arrangement is obtained when the coefficient of static friction is 
greater than the tangent of the taper angle, self-releasing otherwise.

I have found in many such chisels a bur at the opening but am not sure 
if these are put there on purpose to bite into the handle to retain it 
or are the result of abusive ninnies hammering on the bare socket.  The 
thought makes my head hurt.  In any event, such handles must fit 
precisely in order to stay put, unless one uses a very long and narrow 
taper.

The third style is a hybrid where the socket is a separate piece from 
the chisel, which has a shoulder and narrow, pointy tapered tang.  The 
socket slips over the tang and against the shoulder.  The taper of the 
handle is driven onto the tang and inside the socket, which is something 
like a large and relatively heavy, tapered ferrule.  The tang presses 
outward on the wood, seating the handle very tightly both in the socket 
and on the tang.  There is also a shoulder often cut on the handle 
itself such that when it is driven hard it will seat against the end of 
the socket before the end of the handle within the socket seats against 
the shoulder on the chisel.  This provides the best of both worlds and I 
have always preferred this arrangement.  Years ago I had occasion to 
make a 3" slick this way.  Seemed to work well enough.


   I can make the bevel
> match and knock the socket over the wood and get a good friction fit,
> but should it be held with anything like epoxy or ?

No glue necessary and not desirable because someone, some day, will need 
to change it.  Besides, if a mallet is ever used, for example if it is a 
firmer chisel used in chopping mortises, the epoxy will fail in no time.

>I know they're supposed to be able to come
> apart for different length of handles for the job at hand, unless one
> has enough of the same size chisel for all the handle
> lengths.........

I've never heard this before.  The handle on a chisel must be absolutely 
firmly affixed.  It is a matter of safety for one thing and of tool 
efficiency.  In operation the tool must be very predictable in the path 
it is going to take through the wood.  A handle that is loose to even 
imperceptible degrees will diminish that predictability and as such 
poses a very definite safety hazard in a manner similar to that posed by 
a dull edge.