- Joined
- Jun 7, 2013
- Messages
- 10,004
Sash weights were mostly made out of what remained in the "pot" after all the molds were poured, literally "the bottom of the pot" it did not matter what the pour was, what the metal was suited for, how much slag it might contain, it was used to prevent waste of metal, and no need to go into the "rattler" to remove the burnt on "skin" and the chilled iron can take the edge right off most tools.It's no problem if you set up the shop vac with the nozzle near the cutter. Can be very messy but the stuff machines very well (sash weights and old railings not included!)
The iron that I've machined, has never had hard spots or inclusions, being cast by reputable foundries, I especially like to machine nodular iron, it has the strength of steel, but even in high strength formulations, machines easily. When I was building my compound steam launch engines, I had the two throw crankshafts made of 100-70-03 nodular iron, it has a 100,000 psi tensile strength, but still machines nicely and easily; I look forward to machining iron, and use Boraxo to wash it off me.