I would say that the 4 1/2" abrasive disk is the worst choice of all for
cutting thick materials that are wide, where the abrasive wheel is more
or less buried in the stock. ---Especially when hand-held.
A 14" chop saw, although messy, can be a good choice for
(solid)rounds, squares and rectangles, up to about 2" X 2" in my mind.
Tubes can be even bigger, since the wheel isn't in contact with all
that much material. the big problem, (again, in my mind) is that when
cutting materials where the wheel is deep in the material, the sides of
the wheel rub in the cut. This makes the wheel slightly tapered from
the cutting edge back toward the saw arbor. So, as the wheel goes
deeper, not only does the edge of the wheel cut, but the sides have to
cut as well to widen the cut to accept the thickest part of the wheel.
This takes a LOT of power and therefore, cutting action almost stops!


For cutting jobs as you have there, I use a "gas ax"; (oxy-propane
cutting torch). It doesn't care whether you are going straight or
curving. Plan for the rough kerf (depends on your skill level) and
grind to finish.

For the occasional cut, take the piece to a local fab shop. The one I
usually use considers 1/2" thick plate to be "sheet metal" and shears
it. One "thunk" and it's done.

I have a Porta band and like it a lot where it fits the work.

The saw that gets the most use in my shop is the 4X6 horizontal/vertical
band saw.

One other approach is the do the cutting on a horizontal milling
machine, using a slitting saw. There, you are only limited by the X
length of the table traverse.

Pete Stanaitis
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