Im on board.

If this is mid level then its a good idea to go with linear rails or at least supported round rail. Ive not had a good experience with leadscrews and delrin but many have, and espesially if the rest of the machine is well designed. :whistling: might be a way to compromies on the cost......

My machining skills are limited and cnc knowledge is growing but I do understand structures and forces so could help here if required.

I'm currently looking at a composite beam design that uses mateials to their best and combine to form an effecient structure.

As I understand it Cast iron is the choice of a professional machine as it is rigid, strong and dense enought to damp vibration. and it is the small movements (deflection)from the vibration that cause poor surface finish or in worst cases tool breakage.

But the high density has the problem of being heavy so requires large motors to move. I propose to use an aluminum skin as a former, and for asthetic reasons, but filled with concrete and steel of the correct proportions and place to make a cheap beam that is much stonger than ali extrusions, able to provide moderate damping but not be to heavy.

I know this sounds similar to the epoxy granite idea but will be much cheaper and hopfully stronger. Its still only an idea and I havent done any calcs yet but the principle has been used in buildings for many years and yeilds a 50% saving in materials for the same strength.

Sorry if this is off topic but seems a logical approch to an affordable mid range machine.

Any one have any data on cutting forces? I seem to remember 20N for Ali for some reason :whistling:Probably wrong tho.

Ok wake up. I've finnished :heehee:
Later