.0625 woodruff cutter

[miketheknife]

I have to machine a 2" long 3mm keyway in mild steel I intend to use a 1/16" thick woodruff key cutter What speeds and feeds and depth of cut per pass would anybody recommend

Thanks
Mike

[One of Many]

I have to machine a 2" long 3mm keyway in mild steel I intend to use a 1/16" dia. woodruff key cutter What speeds and feeds and depth of cuts per pass would anybody recommend

Thanks
Mike

Woodruff key cutters will not be 1/16" in diameter. They are side cutting and designed to cut a sunken keyway with a width to thickness ratio based on torque shear loads. So, the actual diameter does not work out to standard inch increments. Say a 3mm metric key cutter will be 10.5mm diameter and a 1/16" key cutter will be .505" diameter.

Key cutter Dim's

That said, they can still be used to cut a long key way, T-slot etc. As long as the application does not require a captured key since these cutters will leave a radius at both ends of the cut beyond the length of the key to be used.

If a captured key way is expected, an end mill would be used. Best to start the key slot with a smaller cutter and finish by moving side to side. Using a cutter the size of the key can cut the slot oversize more often than not.

Feeds and speeds are based on the materials SF/M. Mild steels fall into the 50-150sfm range. Conservatively, I'd stay with the mid to lower end of that as not to compromise the cutter life without flood coolant. The rest can be calculated, but again stay conservative on the feed rate per tooth of .001-.002 and your IPM around 4 or less. Maybe .06 depth of cut.

I know this does not match this feed rate calculator, but by experience, overloading a cutter always gets ugly. Feeds and speeds assume optimal cutting conditions. Machine and set up rigidity can introduce chatter and a host of other undesireable circumstances. Therefore cutting forces need to be adjusted to suit rather than relied on as calculated.

Calculators/SpeedsFeeds.aspx


DC