Brian Sharrock wrote:

There ae many instances when it is necessary to utilise a table=saw without
a riving knife and or crown guard. Instances that spring to mind might be
_coving_ a plank; producing tenons; trenching (dado-ing) a board etc. etc.
A crown guard may only be used when a complete cut _through_ a board is
required.

Part of this is a design limitation of some saws where the crown guard
can't be remove without also taking off the riving knife. Things like
tenons, dados, trenches etc can be cut with a riving knife present. The
only operations where the knife will certainly cause a problem (that I
can think of) is cove cutting, and plunge cutting.

Crown guards can be used far more often if they do not require support
metalwork that passes through the line of cut.


--
Cheers,

John.

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