Leveling a CNC Machine

[samualt]

I've been looking at different systems to level my cnc machine. It is especially important in my case because my machine is made to be stored and setup repeatably. Here is one way I thought of that doesn't look expensive or difficult:

1. Use a rotary laser level that is self-leveling to determine if your x-axis is correct. These can bought for under $75 on ebay (make sure it says "self-leveling" and "360 degrees" and "rotary". It should also state the rpm). This is as simple as setting the laser level in the middle of the table and letting it produce a 360 degree line. Adjust the height of the line to match the tops of your x-axis rails. If the line matches all four corners of your x-axis rails then they are level. Otherwise adjust your machine feet or use shims.
2. A simple horizontal bubble level on your z-axis will tell you if it is exactly perpendicular to the x-axis. You could just use any small level you had against the z-axis plate (plate that holds your router).

I can't think of an easier way without allot of measurments and such. The above method makes sure that not only is either side of the x-axis level but also that both sides are level with each other. Assuming the x-axis is perfectly level then the z-axis needs no more than the cheap, small, bubble level.

Does that sound reasonable?
Anyone know of a faster or better way? (must make sure both x-axis rails are level, and level with each other).
I'm not sure of the accuracy of these rotary laser levels but I would assume within a few feet it would be pretty accurate. Anyone know different?

P.S. Look for these rotary laser levels to be dirt cheap in retail around next Christmass.

[trubleshtr]

Did would depend on what type of accuracy you wanted, the average Lasers typicaly are out by a few degrees over several meters unless you buy a laser set-up designed for acurate set-ups $$$$. They act like transit's (or theodilites).
Precision leveles are the normal way for machine builders to level with accuracy, providing the machine itself has a precision surface to mount the level., but these too can be quite expensive ($500-1000 for 8" level)
A regular torpedo level and a real keen eye can get you most the way if you are not after thousands of an inch for accuracy.
Once you have it set-up, consider benchmarking key items or better yet drill and dowel pin for location, you can buy metal dowel pins that are threaded, to remove easier with a slide hammer, simply returning the dowel pins to their holes at set-up will gaurentee accuracy as metal dowel pins themselves are usually accurate to within a few thou of an inch. Drill rod can also be used as dowel pins as it too is very accurate........