The welded steel frame with epoxy leveling is a well established design but the comment has been made more than once that welded steel contains stresses that will distort the frame over time unless the whole thing is heat treated. My two questions are:

1) Has anyone got some real life experience of a frame that has changed shape over time and how badly has it affected your machine?

2) If I eventually get round to welding up a new base frame for my machine will throwing it on a bonfire of old palettes etc. count as adequate heat treatment?