[dazp1976]

Started with the column and is bang on after shimming. Was leaning back slightly.

Problem is the head is out by at least 0.6mm leaning forward which seems a hell of a lot!
That will be a LOT of packing and the more I do the more I'm not so keen to have it like that.

What do you suggest?
So far I'm thinking of putting a small spacer plate between head and Z saddle that is deliberately thicker at one end. Nothing big, just 3mm thickness or so.
Don't really want to strip it all again.

I used a decent enough 90deg angle piece for the column.
Going to make an ally set square on the Sieg to double check it but I'm confident it's right.

I've had my digital angle tool on there too.
Result was:
Y dovetail slides = 0deg
Y table = 0deg
Z dovetail slides = 90deg
Z saddle = 90deg
Spindle/quill = 90.7deg

[dazp1976]

So I've worked out. That if I have a piece of plate skimmed so that it's 0.16mm thinner at one end and then bolted to the back of the head. I can get both the column and the head trammed close to 0mm across the Z and Y axis. The thinner part being put at the top.
Haven't got any longer head bolts so for now I figure I can use a piece that's 4mm thick and bolt it on as is.

For now I've tilted the column back by using aluminium foil shims of 0.16mm thickness to get the Y axis alone level. Technically the machine is within the listed tolerance of 0.1mm across Z and Y but I want it much closer than that. Sigh.