On Oct 15, 6:03*am, Jim Wilkins wrote:
On Oct 13, 1:28*pm, xman wrote:

I notice most of my suppliers don't stock iron.

I use steel and aluminum for most of my stuff. Would like to try some
iron.

I know barbells, some flywheels (bike exercise equipment) are iron.

any ideas?

Do you mean wrought iron or cast iron?

Mild steel that's been heated red and cooled slowly in a fire is close
to wrought iron.

I've machined Chinese cast iron exercise weights a few times. A light
cut with carbide showed the hard spots which are lighter colored and
shinier. After grinding them out, frequently resharpened HSS was
enough to rough out the shape. I switched back to carbide for the
finish cut. My lathe is old and worn and tends to chip carbide on
heavier cuts.

Water pipe fittings are an easily machined grade of cast iron. You
might find a wider range of shapes and sizes and wall thicknesses at a
plumbing supplier than a retail store.

jsw

Pipe fittings are malleable iron, not the same as gray iron. They go
through a heat treat process that changes the structure, also makes it
easier to machine.

As far as barbell weights and sash weights, they're not machined
parts, except for holes in the barbell weights. My experience with
sash weights is that they're full of blowholes, generally chilled, and
will take the edge right off any tool you care to rub up against
them. I got to toss about 400 lbs of them into a recycler skip, most
broke up from a 10' drop. Probably the dregs of the dregs of the
cupola, they made sash weights out of any batch of metal that wasn't
fit for anything else. Probably the barbell weights are the same.

I've gotten some continuous cast rounds that have had a soft core but
the outer inch or so was high-carbide, apparently got chilled in the
processing. Ended up doing a very rough anneal on them, that helped,
but didn't get rid of all the carbide. There's a specific heat-
cooling regimen that needs to be done to get the structure back to
graphitic cast iron and I don't have the equipment for that. The
swarf from the inner parts was the usual black powdery stuff, changed
to silver when the bit hit the carbide layer and started squealing
like a pig. The tool edge went shortly after.

Unchilled gray iron machines like a dream, it's actually soft enough
that a guy can whittle on it with a pocket knife. Kind of the
pinewood of the Industrial Revolution. Downside is that you get a
whole lot of powdery black stuff off of it, all that free graphite
mixed with the iron dust. Way covers are a Good Idea.

If the O.P. really wants to get into it, Lindsey Books has a number of
backyard foundry books, scrap engine blocks and heads would be one
source for casting material.

Stan