You can get more years out of your tattoo machine if you use it with care, and keep it maintained regularly. The constant vibration that goes with frequent use of the machine can get some of the screws and wires loose, so a few adjustments may be needed to avoid frequent cut outs and stoppages.
Part of your regular maintenance routine should be checking your contact points, your power pack and your clip cord, which are usually the problem areas that cause cut outs and stoppages on tattoo machines. You have to make sure that there is good connectivity between your contact points and screws. Check your power pack regularly as well for efficient performance.
What can deter connectivity is carbon build up along the contact points, the screws and even the front spring. You can easily keep these parts of your tattoo machine clean by using nail files and picks. Sand paper is not really a good material to use for cleaning, because it usually leaves some residue on surfaces.
Aside from the contact points, you should also check the clip cord and the power pack regularly. If your tattoo machine suddenly stops, you may have a short circuit on the cord or if your machine runs on batteries, they may need to be recharged. A short circuit can also happen if something is caught between your contact points.
Make sure that the stoppage is not caused by weak coils. Coil wires can break easily so it is a good idea to check your coils regularly and replace them with new ones.
If after all these adjustments, your tattoo machine is still not working, you may have to take it to a tattoo supply shop and have it checked thoroughly. If nothing else works, it may just be the right time to retire it and get a new one.