I want to check my CNC spindle for accuracy and I was wondering what the method is for this and what kind of gauge I need to use or get? I would normally hire a tech for this, but there is no one in my area.
From Contributor W:
When you say CNC spindle, are you wanting to check tram on the spindle or actual resolution as in distance and square?
You will want the right spindle alignment tool and base. You level out the base first and then you align the spindle to the level base. If you have a flat table machine, the table can be off compared to the spindle. This is normal especially with using the spoilboard. That is why you use a perfect machine surface, usually a granite surface that has been machined perfectly flat! Then you measure with the correct tool to this plate and see how far off you are in the X and Y directly. Depending upon the machine, aligning the spindle is not easy work and no one answer will work. This could be as simple as loosening the mounting bolts slightly and moving the spindle to align it. Or it could involve using carefully placed shims to align your spindle.
You also have to be careful on some machines as it involves removing other units to get to the one you want to align. Then you have to re-align the units you removed. A mark helps get it back into the general area, but once it has been moved. You will have to re-align everything. One you adjust the spindle, then you need to re-measure and possibly re-align if you haven't done it before. This could easily turn a couple hour job for a technician into a couple day job for you. Once you do it over and over it gets easier. Better to just hire a technician to come in and he should be happy to explain to you what he is doing on your specific machine. You can also watch and learn how it is done. This can easily be money saved compared to a machine cutting out of level for a few days!