Indeed, you should open your ears! Sound can tell you a lot about your grinding performance. You can tell a wide range of issues related to the grinder and/or material by listening to the sounds they make.
Reasons to Listen to the Grinder’s Sound
Every angle grinder will have whirring noises, among other sounds. These noises are usually made when its disc is rotating and making contact with a material.
These sounds are normal because these show the power tool’s working. But there are times when the sounds are unusual in their type and pitch. Knocking sounds replaced the whirring noise, the pitch changed, or the sounds become louder.
These changes are likely caused by issues related to the grinder and/or material. You must keep in mind that issues in grinding aren’t usually the result of a single factor.
You have to consider all possible causes and check them before making your diagnosis. Your considerations should include:
- The type and condition of the work piece
- The type and condition of the wheel or disc used
- The heat levels generated by the process
- The sound created during normal grinding
An angle grinder with proper engagement with the work piece has a constant pitch, more or less. You have to keep your ears open when the pitch increases or decreases during the grinding process.
You shouldn’t worry when the pitch changes in a subtle manner. Your worries will start when the pitch becomes inconsistent in a significant way. You should keep your ears open for too high or too low pitch.
Of course, you have to listen well to the angle grinder’s sound when it’s properly used. You can then determine whether its sound is higher or lower than normal.
One of the reasons for unusual pitch in angle grinders is the amount of pressure applied on the material. The rules of thumb are:
- Lower pitch that dips repeatedly – Apply a lighter pressure
- Higher pitch with chatter – Apply a heavier pressure
In the case of a higher pitch, the grinding disc’s likely bouncing across the ridges of the material. The bouncing effect results in the high-pitched chattering noise.
You can practice by handling the grinder at the correct angle. When you can hold it, you may turn on the grinder to begin working.
You may also check the wear pattern on the disc face in relation to the disc thickness. The wear pattern should be double the thickness as a general rule. For example, the wear pattern on a 0.25-inch thick disc should be 0.5-inch on the wheel.
If the wear pattern’s higher than 0.5-inch, then the approach is too flat. If the wear pattern’s too lower than 0.5-inch, then the angle is too high.
The pressure applied on the forward and backward motions. Your natural instinct will likely be to apply more pressure on the forward motion. Your pressure on the backward motion will probably be lighter.
This means that you’re getting the worst of both worlds. On the forward motion, the disc overheats because the disc grains become glazed. On the backward motion, the disc bounces on the material, thus, the chattering sound.
You’re inefficient in your work. This is because the disc doesn’t remove much of the excess weld metal.You can resolve these issues by applying consistent pressure going forward and backward.
You have to avoid applying excessively light and hard pressure. You must let the grains do the work for which these were designed.But pressure isn’t all there is to the unusual sounds coming from an angle grinder.
You should also look into the following possible solutions for low- and high-pitched sounds.
Sudden Increase in Pitch
This can be caused by issues related to wheel speed, stock removal, and feed rates, among others. The possible solutions can be a few or several of the following:
When we say sufficient support, we are referring to the body’s neutral position while in a sleeping posture meaning:
- Decrease stock removal
- Decrease wheel speed
- Increase traverse feed rate and dressing amount
- Increase traverse feed rate and in-feed rate
- Increase either coolant pressure or volume
- Raise coolant concentration
Sudden Decrease in Pitch
The possible solutions include the following:
- Increase wheel speed
- Increase the angle setting of the dresser
- Increase coolant pressure or volume
- Decrease stock removal
- Decrease traverse feed rate and in-feed rate
- Decrease traverse feed rate and dressing amount
The use of an angle grinder will always result in grinding or whirring noises. But you have to be aware of unusual noises emitted by your angle grinder.
Your practiced ear will come in handy in determining the possible cause for them. You can then decide on the right solutions for the root cause, thanks to your extensive training.
Remember that there are other possible causes and solutions to changes in grinder sounds. Your experienced ear and informed judgment can find the right remedies for these things.