Lathe Metal Finish Problem
I have noticed that ever piece that I turn in my lathe comes out with a wavy finish on it. Steel, aluminum, light cut heavy cut, there is a definite wavy pattern. I have had this Enco lathe for 11 years and this is the first time I have ever had this problem. Could it be a bearing preload problem in the headstock?
I'm no expert,but if it were my machine first thing I would do is chuck a piece of stock up something beefy sticking out like 2' then put an indicator on the face and OD of chuck and give the stock a tug and push to see if there is any noticeable play.I may be wrong but I would imagine you shouldn't get more than .002 travel on the indicators with moderate pressure on the chucked stock.
We had a lathe do similar cuts and the problem with it was the saddle was floating around on the bed.Had to drop the carriage to get to the adjusting screws that worked like a gib to hold the saddle down on the v ways.I moved it down to the far end of the lathe were the least amount of wear was and readjusted the screws that held the saddle down to bed and it worked fine afterwords.There were something like 6 set screws with brass ends on each side of the lathe,they were locked in place with a jam nut to keep them from backing off.