Consider These 6 PROMINENT Things before Buying a Used or Second Hand CNC Machine
2. Age Inspection of used CNC machine
When CNC machines are properly cared for, they can last for many years. This is one of the first things you should consider when looking at a used CNC machine. Obviously, it’s best to purchase the newest model you can afford, but older models can still function at peak capacity if they have been properly cared for and received regular maintenance and cleaning.
If you’re running a big operation where fast production speed is crucial, you should be certain that the used machine you’re looking at is capable of meeting the high demands of your business. A used CNC machine can be more than capable of producing what you need it to, but when you know that you’ll be using it often and running it for long periods at a time, you should avoid purchasing one that was used for the same reason. If this is the situation you’re in, then you should focus your search on CNC machines with a low hour count.
4. Check the Spindle
Run the spindle at multiple RPMS (50, 100, 1000, 5000, Max) and check for any noises.
Keep your hand on the casting and put the machine in rapid mode at 50 percent and move them. Try to feel if there's some oscillation. Listen for a low growl or any abnormal noise while operating in the rapid mode. This could mean that there are bad bearings, ball screw and worn ways. Listen to each of the servo motors for a high pitch humming. This could mean there are some problems as well
You should always make sure that a used CNC machine has been well maintained before you purchase it. You should ask the seller how often is has received cleaning and routine maintenance, and, if possible, you should also ask to see the proof of services performed. Sellers don’t always have these documents on hand, but if they do, they can go a long way toward putting your mind at ease. Also ensure that the machine has been upgraded to suit your needs, or that it is capable of being upgraded at all. If you plan on performing complex machining, you may require more advanced controls than what were originally included. Make sure to research the availability of replacement components and upgradable parts.
CNC Lathe Machines
Run an indicator on a few pockets to see how straight they are. You may see a gradual incline or decline which means that it is out of alignment. The important thing is to make sure it is gradual and there are no high spots and also to make sure all of the turret stations are the same. If the pockets are distorted then you will have problems keeping your drills on center and in other tooling