iron for machining

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?

Reply to
xman
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There's iron and there's iron. If you mean "cast iron" then you need to get some that's of a grade to be machinable -- it is very easy to cool cast iron too quickly for easy machinability, leaving it brittle and hard.

McMaster carries it (spendy!). Dunno about Enco or other suppliers, but you could check. Some older cars used cast iron crankshafts, but I've never done anything more than toy with the notion of trying to cut good bits out of them, and you'd certainly want to know if it was cast you're using and not forged steel.

Much cast iron is going to be cast in shapes already, making it hard to machine anything useful.

Reply to
Tim Wescott

You may want to differentiate between iron and cast iron. Iron as a pure material is not used for much but is sort after by blacksmiths as it can be worked at higher temperatures than steel. Steel is an iron carbon alloy at it simplest, typically having up to 1% or thereabout carbon. Cast iron typically has between 2% to 4% carbon. barbells and flywheels are typically cast iron. If cast iron is what you want then you may want to try asking for Meehanite which is a continuously cast material.

Reply to
David Billington

It is available in block, bar and plate in multiple flavors on the web....Google it. Steve

Reply to
Steve Lusardi

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I've machined many foundry patterns out of 40K psi (V2) gray iron from the above company. Is a wonderful material to work with.

Reply to
Black Dragon

FYI:

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"The Meehanite Process In a Nutshell

The dense, fine grain structure of Meehanite metal which assures casting solidity and consistent physical properties relate the carbide stability of the molten metal, both before and after processing to the casting section. These controls which are the basis of a series of patents dating back to 1927 are fundamental to the Meehanite process and are the primary reasons for the structural integrity exhibited by Meehanite castings.

Expressed in it's simplest form, Meehanite metal is first melted to a definite degree of undercooling or constitution which is related to the section of the casting to be poured and the range of physical properties such as tensile strength and hardness required. Nucleation with patented mixtures of graphitizing agents results in the removal of undercooling, in the controlled precipitation of graphite and in a fine grained eutectic cell structure which determines the density and physical integrity of the casting. Ordinary cast irons made to chemical specifications which do not include the benefit of controlled undercooling are influenced by mass effect to a maximum degree and for this and other reasons cannot be considered an equivalent to Meehanite metal."

Reply to
Black Dragon

I've used trailer wheel hubs to make a lathe face plate and a chuck backing plate. I've also used a barbell weight retaining collar. All cast iron ... machined nicely, as I recall.

Bob

Reply to
Bob Engelhardt

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

Reply to
stans4

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