On Fri, 25 Jun 2010 17:03:51 -0400, Jack Stein wrote:

wrote:
On Jun 25, 8:05 am, Jack Stein wrote:
Leon wrote:

These type cutters tend to require more hp because of the relative constant
contact with the wood as opposed to the straight knife cutters. Your
mileage may vary.

I've been seriously considering buying a Griz with a spiral cutter head.
I would think only a fraction of the surface would be cutting since
the head is made up of lots of small cutters in a circular spiral, so it
would seem LESS hp would be required than from a 15" knife contacting
all at once?

I don't think that's a good assumption at all. The same work is being
done.

The same work is not being done at the same time. Instead of cutting
15" wide swath each time a knife contacts the wood, only an inch or
whatever width a knife insert is cuts, so the work is spread out in lots
of little chunks instead 3 wide swaths. On the other hand, I reckon the
same amount of wood is cut at each full revolution, so you might be right.

Unless the knives stall when cutting, it's not going to matter. That's what
momentum is for. If you haven't got enough of it, get a bigger flywheel.

Anyway, the main reasons I want one is it handles wild grain better, but
also makes a lot less noise. I don't care much about the noise part but
I figure the reason it makes less noise is because it cuts more
efficiently, ie, needs less HP due to just one small cutter in contact
at a time.

I would expect knives to be a lot more expensive, though.

Yes, but an old lumber yard I used to go to had a big planer with a
spiral, segmented cutter head and it was one sweat machine. Wild,
opposing grain just doesn't plane well and I think I'd rather spend the
cash on a cutter head and be done with it. I'm more concerned with
maintenance, as in sharpening and installing a bunch of cutters as
opposed to 3 long knives. It could be easier, I have no clue? I can
manage my 3 knife jointer with out too much fuss, that I know.

Likely as much as I do. I would go with the spiral cutters if they really did
a better job. I'm not buying the lower power, though.