Safety Instructions & Gear - Grinding Wheel Ring Test - CRATEX Abrasives

The manufacturers have a great responsibility to produce grinding wheels that are safe to use, but no matter how careful they are during the production, they have very little control over the products once they are shipped and delivered to the customer. The consumers are the ones who should make sure that the wheels are handled, stored, mounted and maintained properly. If not, their behavior can contribute to an unfortunate accident resulting in painful or debilitating injuries to both the operator or others present.

It is advisable that the storage room has a constant level of temperature and humidity since the variations ca damage the bonds in some wheels. The wheels should also be protected from banging and kept in a secured spot. To avoid bumping or dropping them, pay special attention to the way you handle them.

The Ring Test

Grinding wheels are breakable and can be extremely dangerous if used damaged. They can contain microscopic cracks in them which will cause them to explode at high speeds and send shrapnel flying across your workspace in all directions. It is essential to inspect every grinding wheel before you mount it and use it, regardless if it is a used one or it’s brand new that you took right out of the box. Remember – the wheel can seem to be in a perfect condition, but that might not be the case.

Since a cracked wheel can cause serious injury to the human body, and be lethal even, it is fortunate that there is a quick and simple way to test if your wheel is good to go or not. This is determined by a Ring test, and the name is self-explicatory, really: the grinding wheel is hanged on a screwdriver blade and suspended in the air. Next, you’ll visually divide the grinding wheel into 8 equal parts (best is to imagine pizza slices), you’ll take the second screwdriver by the blade, and you’ll tap 8 times, once in each slice with it’s handle. You’ll start at the top, then the bottom, left and right, following the cross shape, and then in remaining parts.

A high-pitched ring sound will tell you that the wheel is in perfect condition, and if you don’t hear it, but hear a dull thud, it means that the wheel has cracks in it.

Safety Gear

Angle grinders produce sparks when grinding ferrous metals and shards when cutting other materials. In addition, there is a possibility the blades could break, so safety goggles or a full-face shield and protective clothing (work gloves, fire-retardant clothing) is a must when grinding. Otherwise, the risk of seriously injuring your face damaging your eyesight is great. Angle grinders should always be used with their guard and handle, and the workpiece should always be firmly secured in a vise. Hearing protection is also necessary, as the grinders are often very loud, especially when cutting. Since abrasive cutting generates a lot of dust, different kinds of masked can be used depending on the material you’re working on.

When working on a bench grinder, it is essential to note the maximum rpm ratings that are printed on the wheel label. The rpm of the grinder must be either equal or lower than the wheel’s rpm. An overspeeding grinding wheel is bound to explode, which can be lethal. Wheel guards are there to intercept the exploding fragments, so make sure you never use a bench grinder without the wheel guards.