"Buerste" wrote in message
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"Harold and Susan Vordos" wrote in message
.. .

"rodjava" wrote in message
...
I was planning a project which calls for a simple milled t-slot in
some mild steel.
I don't have the cutter yet. What is the difference in a Woodruff and
T-slot cutter?

Can a Woodruff cutter act as a T-slot cutter and vise versa?

Which cutter would have a dual purpose and be the most useful?

Thank you in advance for your help.

Rod
San Francisco

You're likely to discover that a T slot cutter is side cutting, whereas a
Woodruff cutter is not. Both can function in the same capacity.
Woodruff cutters don't have the ability to cut on their sides, but they
are hollow ground for relief, and can be stepped over and plunged to
achieve slots of specific widths.

A Woodruff cutter demands that the spindle be at a right angle to the
cut, otherwise there can be loading that isn't desirable. A T slot
cutter will cut in most any attitude, although proper head alignment is
desirable.

I don't know that one is better than the other, although you may find one
has features that are more desirable for certain applications than the
other. Woodruff keys and keyways are expected to be held to a tight
tolerance, thus the lack of side cutting. T slots generally have a
greater tolerance, so if the cutter cuts slightly oversized, no big deal.
Let your need determine which would serve you best.

Harold


I've never had to cut "T" slots but the thought scares me. Is that
operation as hairy as it appears to be to me? Or, just another irrational
fear?

Many factors will play into the results you achieve, and the problems you
face. One of them is the size of the T slot, as well as the material you
intend to machine. Rigidity of the machines is also a huge factor. If
you have a large slot to machine and it's in steel, running a light duty
machine, you'd do well to rough the slot with an undersized cutter, one that
maybe is narrow in height and somewhat smaller than the full diameter (width
of the finished slot). Rough all of the features aside from the opening in
the slot, then take it to size. That can be useful in all cases, truth be
known. Be certain to lube the cutter well, although if you machine gray or
ductile iron, you likely will not need lubrication.

Steels of all kinds will demand more from the machine, and aluminum will
demand less. Do what you can to keep chips from accumulating in the cut.
Provide air if you have it available---to clear the cut. If you allow
chips to accumulate, you'll have grief.

The more area you have in contact with a cutter, the greater will be the
demand from the machine---in all ways. Minimize the amount of material that
is removed (per pass) and you'll lower the effort required. Opening the
straight portion of the T slot is a good way to eliminate a lot of material.
You can do that with an undersized end mill. Stop slightly short of
finished width and depth, then rough the T, leaving a few thou for a finish
cut. Go back and finish the slot with an end mill, then take your finish
cut(s) on the T with the cutter you chose to use.

Don't let the task intimidate you---take it easy and feel your way as you
go. Don't run the cutter beyond recommended surface speed, to avoid killing
the cutting edge-----especially if you run a carbon steel cutter.

Such cuts can go smoothly, or give you fits. Make sure you lock the saddle
and spindle when you take a cut with the table. Use good sense and you
shouldn't have trouble.

Harold