A good quality grinder for stained glass work is one of the biggest expenses in starting or advancing your hobby.  Since they can cost up to about $200, making sure that proper maintenance is performed on them is crucial to ensuring years of trouble-free operation.

All grinders are designed to transfer water from a reservoir to the grinding surface, preventing the glass or the diamond surface from overheating.  If the grinder is run dry, or with little water, the glass can overheat and crack, or the diamond coating on the grinder bit can be worn off quickly.  Some grinders transfer water through a sponge, and some with a spray nozzle, but all need to be able to access water for coolant.  If the water reservoir is clogged with glass sludge, it can make it difficult or impossible to keep a constant supply of water.  Some brands of grinder have a lift-off reservoir that makes cleanup a snap.  Others have fixed reservoirs that require scooping out the glass sludge that builds up during use. 

Regardless of which method your grinder uses, the important thing to remember is NOT to rinse the sludge down your drain.  If you’ve ever let a grinder dry out, you’ve probably noticed how the glass residue hardens into a solid layer of gunk in the water reservoir.  Now imagine if that same layer of hard sludge was inside your pipes, and you can readily see why you wouldn’t want it going down your drain!  Always perform the cleanup while it is wet, so you avoid any potentially harmful glass dust from getting breathed in, and discard the sludge in a sealed bag or container.

Another step that needs to be taken as part of your grinder maintenance is lubricating the motor shaft, so the bit doesn’t seize up and lock fast to the shaft.  Nothing is worse than getting ready to re-position the diamond grinding bit, and finding that it’s rusted fast to the motor shaft.  Get in the habit of re-lubricating the motor shaft each time you re-position the grinding bit.  Some people use Vaseline, but our preferred method is to take WD-40 and spray it onto a paper towel, and then run the paper towel up and down the motor shaft to oil it.  This prevents excess liquid from pooling in the motor, and doesn’t attract dirt like a stickier substance (like Vaseline) can.  When re-lubricating the motor shaft, also take the time to oil the set screw on the side of the grinder bit.  Take it completely out, and give the threads of the set screw a quick squirt of WD-40 to ensure that it doesn’t rust fast to the motor shaft.

As you use the grinder, the sharp edges of the glass will scratch and cut up the work surface of the grinder.  This isn’t a problem, until the scratches get large enough to start catching the edge of the glass as you slide it over the work surface during use.  Instead of just buying a new surface, you can make your existing one work much better by simply sanding down the rough spots.  A palm sander can make quick work of sharp points that catch glass edges, and can make your work surface last for many more years.

We hope you’ve enjoyed our grinder maintenance tutorial, and be sure to check our other guides for more helpful information about stained glass.  Also, be sure to visit our eBay store for a wide selection of quality tools and supplies for all your stained glass needs, including the largest selection of sizes and colors of bevels on eBay!