Good question, see the http://www.patwarner.com/patternbits.html link
for some background.
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> This might sound like a silly question but why would I need pattern
> bits with different diameters ? I'm thinking the more intricate the
> pattern the smaller the diameter.
>
> Thanks.
Depends on how much you're trying to hog off in a single pass. I use them
for triming up curves after roughing them out on the bandsaw (large radius
curves like the arched back of a bench for example). So in my case I'm not
trying to follow intricate patterns so much as I'm avoiding spending time on
the drum sander :) And I like to use a large diameter pattern bit (1/2" in
my case, don't want to go so big as to stress my router either) so it takes
the stress better.
They also make dado cleanup bits (real shallow bits with a bearing at the
top) to flatten the bottoms of dados cut on a tablesaw (guess you'd only do
this if you were to see the dado from the side -- the bevel edges that
precut the edges to relieve tearout would be noticable in this case). These
range from 1/4" up to 3/4" in size.
Mike
"Joe I" <[email protected]> wrote in message
news:[email protected]...
> This might sound like a silly question but why would I need pattern
> bits with different diameters ? I'm thinking the more intricate the
> pattern the smaller the diameter.
>
> Thanks.