Reconditioning a Relmac lathe

[Robin Hewitt]

Okay :D If they never machined it it has to be cast :D

You can't preheat the cast iron mould because you don want to detemper the spindle. You can't upend it and pour from the front because you can't remove the spindle to clean it up afterwards.

Suggestions :D

Get a lot more heat in the metal before you pour, howsabout barbeque charcoal.

A deep well around the sprue so you can pour faster.

A damp leather pad on a wood backing that you can put over the well. This is an old goldsmith's trick, steam forces the metal in.

Consider cuttle fish bone to seal the mould and make the well. It is very easy to cut, lets the air out and doesn't burn.

[irving2008]

... You can't preheat the cast iron mould because you don want to detemper the spindle. You can't upend it and pour from the front because you can't remove the spindle to clean it up afterwards...

I wouldnt have thought it would have been hot enough to detemper the spindle... Its been suggested it needs to be at 150degC or so, the bearing metal melts at 380degC-ish, neither of which are hot enough to detemper a steel spindle, agreed?