hi all, i have just brought a used arrow 500 and now its set up i have done a bit of machining with it.

it seams ok and very nice to set up and use but i am struggling to get a good surface finish, only machined 7075 T651 so far and the machine seams to be lacking in rigidity. even with light finishing cuts i am getting a ruff surface with a face mill and when profiling i just get a dull irregular judder almost. the machine indexes very well but there seams to be a fair bit of play between the bed and the spindle (side to side not up and down)

i am more used to brand new machines with hardened box ways at work but this is for my own stuff at home so a brand new machine is not an option, am i expecting to much from an old machine with linear bearings? would it be worth putting new linear bearings in the Z? or all round for that matter?

if anyone with experience of these machines could give there ideas that would be great!

thanks in advance,
Richard