On 03/25/2015 09:10 AM, John McCoy wrote:
Doug Winterburn wrote in news:5511f77a$0$46442
:

It really does make a difference when cutting both sides. The same
rules apply as when cutting one side as the cutting action of the bit
will tend to keep the router against the guide.

How so? If the cutting edge on the right side of the groove
is pulling towards the template, then the cutting edge on
the left side of the groove is pushing away. They cancel
each other out.

It's about the leading edge of the bit in the grove where the cutting is
occuring, not the sides.

Other than when starting a groove with a non-plunge router
it shouldn't make a difference (when starting only one
side of the bit cuts, of course).

John


Experience is the best teacher.

The best way to prove it to yourself is to give it a try in both
directions with very slight pressure against the guide.


--
"Socialism is a philosophy of failure,the creed of ignorance, and the
gospel of envy, its inherent virtue is the equal sharing of misery"
-Winston Churchill