In an ideal workshop, an ammeter is always present. But because we don’t live in an ideal world, we have to keep an eye on spark flow while grinding. Your eyes are also the best gauge of spark flow, even in precision jobs.
Reason to Keep an Eye on Spark Flow
The rationale in being aware of the grinder’s spark flow is simple. The spark flow is a good sign of the pressure applied on the work piece.The grinder may be pushing too hard or too little against the metal.
You have to make the necessary adjustments, ASAP. Indeed, grinding can appear simple to the untrained eye, but it isn’t. Effective grinding demands that the operator combines three crucial aspects:
- The application of enough pressure on the material from the grinder’s disc
- The angle of approach should be between 5 and 10 degrees from the horizontal
- The duration of the contact should be best to the job
Even a simple miscalculation in one of these factors can result in unsatisfactory results. Your risks for injuries also increase.
The Main Goal
Let the grains remove most of the welded metal in the shortest possible time. The disc and grinding tool shouldn’t be prematurely worn or burned out in the process, too.
By keeping an eye on the spark flow, you can adjust the pressure and angle of approach. Your work piece will likely come out according to pre-set standards for this reason.
Tips in Looking at Spark Flow
You can use two methods in keeping an eye on the spark flow. Your best bet is to use both methods for best results since digital and visual means work well together.
First, you can use an ammeter in determining the current in a circuit. When it’s hooked to an angle grinder, it reveals whether the applied pressure is too much or too little.
The right pressure will depend on the tool and its grinding wheel’s rating, as well as on the material. But for general industrial applications, it ranges from 8 to 10 amps.
You have to check that the ammeter’s reading stays on this range. The right pressure will depend on the tool and its grinding wheel’s rating, as well as on the material.
But for general industrial applications, it ranges from 8 to 10 amps. You have to check that the ammeter’s reading stays on this range.
If the meter reading exceeds 10 amps, you’re putting too much pressure. You have to decrease it so that the material and disc aren’t grinded beyond the desired point.
If the meter reading falls below 8 amps, your pressure’s too light. You have to increase the pressure to remove the excess weld metal.
Second, you can use your eyes, especially when there’s no ammeter available. You will also find that it contributes to faster and easier work.
You don’t have to check the ammeter’s readings on a regular basis. From the safety of your face shield or goggles, you can look at the spark flow while grinding. Be sure to look out for these signs.
The sparks flow should be about 3 to 4 feet away from the metal. The flow itself should be consistent instead of being on and off while grinding. This means that the grains on the grinding wheel are actually removing the weld metal.
The sparks flow will not be as pronounced or consistent with inappropriate pressure.
If you push too hard, the disc overloads and overheats. You will see the disc’s grains being too smooth so these don’t cut into the weld metal. The spark flow decreases.
If you push too little, the disc isn’t engaged with the weld metal.Both the spark flow and weld metal removal decrease. Indeed, too little and too much pressure on the metal contributes to unsatisfactory results.
You have to look at the spark flow to determine which of these two mistakes is happening. You can then make the necessary adjustments, either putting more or less pressure. You should also look out for these signs in relation to the spark flow.
The grinder’s sound while in operation. You have to listen for a consistent pitch. If it’s too low, then you’re applying too much pressure. If it’s too high, then you’re pushing too little.
For example, a reduced spark flow with a low-pitch sound means you should ease up on the pressure. You have to use both your eyes and ears to determine the best remedial action for the issue.
The type of material for grinding. For example, stainless steel can quickly turn blue under an angle grinder. You have to use a different method – pull-and-lift – so the sparks flow will be different, too.
In fact, you have to change your technique with each type of material. You may also want to reduce the steps in the grinding process. You can, for example, use another abrasive media to cut certain finishing steps.
When using a power tool, you have to use all your senses to determine the work’s progress. This also applies to an angle grinder, a power tool with a highly abrasive capability.
By using your eyes and ears, you can adjust the amount of pressure placed on the material. You can also determine whether your angle of approach and contact duration are appropriate. Your experienced eye can tell all these partly by looking at the spark flow.
You can use an ammeter for keeping an eye on the spark flow. But your eyes and ears are still the better judge of this matter. You can practice on an angle grinder and observe the way expert grinders do it.