For most mortises, the only "passes" you want to make would be on depth of
cut, not width.
Mortise widths are generally based on two things, the width of the material
into which the mortise is being, and/or the width of the chisel with which
it's being cut .
You would do better, IME, to get the exact size router bit for the planned
tenon, ie, 1/4", 3/8", 1/2" ... you can always plane or otherwise adjust the
tenon if need be to get that just right fit.
--
www.e-woodshop.net
Last update: 1/02/04
"Mike W." wrote in message
> If I get a spiral bit or two, should I buy the bit the exact size of the
> mortise/dado that I want or should I buy it smaller and make several
passes?
>
> I'm going to try my hand at some basic mission style rail/stile stuff at
> first like this: http://www.furnitureplans.com/pi_products/1100
I use a 1/4" bit regardless of mortise width and use a template and template
guide. Multiple passes are made for depth only as the full width is plowed
out per pass. The router bit width doesn't necessarily determine the
mortise width.
This page illustrates a template very similar to the ones I've made, and an
identical technique:
http://www.taunton.com/finewoodworking/pages/w00118.asp
A mortising template need not be fancy and complicated.
Brian.
"Mike W." <[email protected]> wrote in message
news:[email protected]...
> If I get a spiral bit or two, should I buy the bit the exact size of the
> mortise/dado that I want or should I buy it smaller and make several
passes?
>
> I'm going to try my hand at some basic mission style rail/stile stuff at
> first like this: http://www.furnitureplans.com/pi_products/1100
>
> Thanks,
> Mike W.
>
>
>