Dear Applications:
Why do CNC machines need to be calibrated?


Dear
All Haas machines are fully inspected for linear accuracy and three-dimensional squareness prior to shipping.
CNC machines, like all types of equipment, are subject to change over time. The thing most likely to change with a machine tool, and most likely to affect accuracy, is the machine’s level. The quality of a machine’s level is crucial to the quality of the parts produced. For this reason, checking a machine’s level should be part of a regularly scheduled preventive maintenance program that is appropriate to the machine and its operating environment.
Sincerely,
Haas Applications

________$$$$$$$$________


My question is this: Do I need a yearly calibration if I am using my machine just for prototyping and Never crashed it.........YET !!!

I check the spindle run-out and linear accuracy if I am not busy....

I need some input regarding this matter.

Thanks,
Burgerboy

Please call me.
Wayne Reilly
Applications Manager
Haas Automation Inc.
805-278-8560

What about the Haas Mini-Mill? The setup instructions specifically say that precision leveling is not necessary.

If you can get by with out checking the level of the machine depends alot on the machine, the foundation and where you are located and the accuracy you wish to maintain. If it is a new installation I would definately recheck the level after a month or two because things do settle. Many smaller verticals are not effected much by level, larger machines usually show more effect. If you are in an area that gets freezing temps in the winter it may even be necessary to check the level a couple of times a year (after the winter freeze and after the spring thaw) If the mill is near an outer wall the movement from freezing and thawing will be greater.

Releveling most machines is pretty easy, you do need a precision level and having 2 people (one to watch the level and one to turn the screws) can really speed things up. If I have to level a machine by myself I will often use a little monitor and video camera so I can see how much the bubble is moving as I turn the screws. On bigger machines where you have to lay on the ground and reach under to get to the screws this can help alot.

Some machines can be a real hassle to level, for example Hardinge's RS lathes come with 3 fixed and 3 adjustable feet. You level the lathe by shimming the the fixed feet untill it is level and then using the adjustable feet. On a 8 ton lathe jacking and shimming is very time consuming.