[hayes]

I dig it! I do have a question though as I just don't know the answer - what would be better from a manufacturing, cost and rigidity perspective - a steel weldment or aged and hardened cast iron casting?

[engnerdan]

I dig it! I do have a question though as I just don't know the answer - what would be better from a manufacturing, cost and rigidity perspective - a steel weldment or aged and hardened cast iron casting?

Well aside from the cost of making the pattern for sand casting, a casting should be much cheaper than a fabrication like this. But making a pattern basically takes as much effort as a fabrication except in wood. I am hoping to I might be able to use the lost foam method and fabricate a copy of the headstock with the foam that is then packed with sand and when the iron is poured in the foam vaporizes.

A weldment will not absorb and suppress vibrations like a casting will. Plus a weldment will need a thorough stress reliving before machining. Additionally to make a mill headstock like this will take a fair amount of time and some expensive pieces of steel. I took a quick look for the steel stock (all higher grade than A36) and I came up with $400-500 in raw stock before cutting, fabricating, welding, heat treat. Stepping down to A36 cuts the cost down to $250-400.



Sometime in the next couple weeks I am going to stop a local foundry that does small odds and ends parts too see what they think of the design I have come up with and see if they can give me a ball park price. At that point I will take a serious look at what path I want to go down.

-Dan