On Tue, 16 Nov 2004 07:42:44 GMT, Bob Martin
wrote:

Andy, I'm a bit confused by this comment. The Freud dado set sold by
Machine Mart (p. 296) specifically states "NOT to be used on any machine
with electric braking".

That's the problem. Most saws (all retail size ?) use a left-handed
nut to lock the blade onto the arbor. With a heavy dado set, rapid
braking may cause this to unscrew.

Laws require moderately rapid braking.

Some saws use simple electric braking to achieve this, which is very
quick indeed.

Rapid braking is definitely unsafe with simple LH nuts.

Therefore you can't use a dado set on a simply made saw consistent
with most of the saws complying with PUWER.

You could achieve this safely with an extra arbor lock. If you have a
3 phase saw with a VFD (variable frequency drive) it's possible to
brake more gently at a controlled rate, which would be safe with dado
heads, rather than simple injection braking. Either of these
mechanisms add cost though and I don't know of machines that do it.

UK practice for a large production shop would be to use a moulding
head on a moulder or planer, rather than a dado head in a table saw.
--
Smert' spamionam