On Wednesday, December 28, 2016 at 4:21:48 PM UTC-5, David Billington wrote:
On 28/12/16 19:44, wrote:
On Wednesday, December 28, 2016 at 8:43:58 AM UTC-5, Ignoramus22750 wrote:
On 2016-12-28, Martin Eastburn wrote:
To hot for mud :-)

I suspect the rods were marked - hole smaller than this - and flange ......

The company doesn't want to pound out another or 50% for mistakes.

Wrought iron not pouring. And the base must be a beast into the ground!
Not much bounce in the ground near by or anywhere.

I think "we" went into pouring the form and then machine out the final.
But cast is not as strong as forged, no?

i
That piece is not iron. It's steel. Of course, if you're a nitpicker, steel is a type of iron. d8-) Big pieces of wrought iron are very rare and have been for around a century.

Cast iron is strong in compression -- stronger than forged (wrought) iron. But, except for ductile iron and malleable, more or less, it's weaker in tension and it's very brittle. You would not open-die forge any ductile or malleable iron to the degree of this example. It's not up to that much hot working.

Again, though, that piece is steel. It's much stronger than wrought iron. The forging will make it a bit stronger, but casting steel is an iffy proposition, anyway.

Why is casting steel an iffy proposition? it's done all the time. My
neighbour was building a miniature US steam locomotive and that
apparently had a one piece cast steel frame which from memory would have
been in full size some 60' to 80' long.

Higher casting temperatures and fairly low fluidity are limiting factors for steel castings. There are other issues that sometimes cause problems, such as shrinkage where section thicknesses change.

A piece like the one in the video clearly is a cutoff section of steel off of the first or second rolling stand; a custom order, probably, because it probably couldn't be made in a modern continuous-casting operation. It's too thick.

--
Ed Huntress