Designing a better bed

[michaelw]

(1)

Designs for any machine beds come in two classes :

(a) Those which are set up in place once only and can remain in place for service life of machine .

(b) Those which have to be more regularly re-sited .

Considering only (a) pro tem the cheapest and most rigid bed is usually a deep cast concrete block with all the precision machine components bolted down to it .

(2)

Composite construction for machine beds is usually non preferred .

Your proposed design would be better with much smaller section reinforcing rods with grip into the epoxy mix . Common ragged reinforcing rods would be ok .

Personally if I wanted to use epoxy concrete construction I would just cast a solid slab of sufficient depth but with no reinforcing at all .

(3)

There are other types of machine bed :

(a) Based on (eg) quarry slabs of rigid slate .

(Think billiard tables and DMM's)

Granite would be super excellent but probably be too expensive for your purpose .

(4)

Consideration must always be given to how machine bed sits on the workshop floor .

Concrete block cast in place on adequate sub surface is usually ok anyway but any slab type bed mounted (relatively) loose on floor needs mountings which do not distort bed and which usually need to allow for some levelling .

Mountings in any case have to sit on floor and sub surface of sufficient rigidity .