Shaper head with router

[chiesa dan]

Hi,
maybe a dumb question, but would it be possible to have some kind of shaper head in a router that cuts a 3" tall profile? It would be in a router table with a big router motor, like a PC 7518.
Thanks,
Daniele.

[Peter Quinn]

Short answer, no way. A router cant spin the mass of a 3" tall shaper cutter effectively, not even in aluminum. There is also an issue with speed versus diameter that would result in excessive tip speed. Most shaper heads have a maximum safe speed well below a routers minimum speed. There are shafts slot that allow you to spin small shaper cutters on a router, but these are typically 1/2" cutters of small diameter and limited height. There are router bits close to 3" tall that require multiple passes, like crown cutters.

[david brum]

The Grizzly 3" shaper head manual specifically says that it should never be run on a 1/2" spindle (like a big router or small shaper) and should be operated at 4000 to 7000 rpm (Your PC min speed is 10,000 rpm). There are plenty of stories about guys who have bent 1"+ spindles. Pretty sure you'd be asking for trouble.

Grizzly manual:
http://cdn7.grizzly.com/manuals/g2606_m.pdf

On the plus side, there are router bits which will cut 5"+ molding:
http://www.eagleamerica.com/product/v175-2515/ea_-_molding_bits

[chiesa dan]

Thank you both; i'll see if i can find a local shop with a good shaper to do that operation for me.
best,
Daniele.