Been busy of late and the conversion of the Seig X1LP super has been succesfull to date, now time to build something from scratch. Started badly as I couldn't resist a bargain and came across a couple of sets of Rails Bearings and screws at the right price Sub £300 delivered. So my starting point now is:
4@ SBR20-300mm Linear guide
4@ SBR20-600mm Linear guide
4@ SBR20-1000mm Linear guide
24@ SBR20UU Linear blocks
2@ SFU / RM 1605-350mm- C7 ballscrew with end machined
2@ SFU / RM 1605-650mm - C7 ballscrew with end machined
2 SFU / RM 1605-1050mm- C7 ballscrew
2@ with end machined
6@ BK12 support for ballscrew

6@ BF12 support for ballscrew
6@ Couplings
Major considerations, I have a workshop in a spare room in my first floor flat so everything gets carried up and down as required, and I try to limit noise to be considerate to neighbours. Been looking at Fusion 360 which I find simple and straightforward to use with the Seig conversion so knocked up a quick mock up of a machine to get some comments and advice sure there are lots of traps I have fallen in to pictures below .
My requirements call for a 700x400mm work area and max 100 mmZ axis. Not included in pictures are 2 SFU / RM 1605-1050mm- C7 ballscrews driving Y axis, either 1 or 2 SFU / RM 1605-650mm - C7 ballscrew driving X axis and single SFU / RM 1605-350mm- C7 ballscrew driving Z axis with a Chinese 2.2 water cooled and VFD. A lot of my strength I am relying on a solid base I intend to bolt whole thing solidly down onto a welded steel framed table with a solid cast iron top.
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Material wise two bed sides are100x100x10mm T section which can be backed up by another 25-35mm plate without losing work area, X and Z main components 25mm and 30mm Ecocast, first draught so nothing much fixed apart from overall size, my idea is based on ease of build, welding in the flat is not an option.