Grinders are rugged and resilient tools, but they’re not invincible. They pack a lot of punch, but even the toughest equipment can require repairs.

Did you have a strong role model as a child? It may have a parent or a sports coach or an older sibling. You probably saw this person as bulletproof. To you, this person was a leader. They weren’t just strong. They were undefeatable.

 

Hopefully you have someone in mind now. If you still keep in touch with this childhood hero now, I’m sure you’ve realized that they’re not as strong and mighty as you thought they were when you were young. You’ve discovered that everyone, even your once invincible role model, has weaknesses and vulnerabilities. It’s impossible to be all-powerful all the time.

 

Like people, grinders have faults and can become worn down as time passes by. No matter how tough your power tool is, eventually it will lose productivity or even break. That means it could be time for a repair.

 

Keep in mind that repair may not always be your best option. Knowing when to repair your grinder versus when to start shopping for a new model is not always easy. But more often than not, repairs are a convenient and economical alternative to having to buy a brand new tool. And over time, these little repairs add up to significantly extend the life of your grinder.

 

If you’re thinking, “I don’t know how to perform any grinder repairs,” don’t worry. It’s important to note that tool service should only be performed by qualified tool personnel. But there are some simple steps you can take to extend the life of your grinder.

 

Whether your tool repair is performed by you or another qualified person, these four easy service tips will make sure you have a power tool that runs great and lasts.

 

Grinder Service Tip #1: Make the Right Preparations

Before assessing the state of your grinder, you must first check yourself. Are you a qualified tool personnel? If not, don’t attempt repairs and take your tool to a repair facility.

 

Believe it or not, power tool repair can be dangerous. Taking apart and exposing yourself to the inner workings of powerful equipment like a grinder could cause serious harm if you don’t know what you’re doing. Not only that, if your grinder isn’t put back together properly after performing repairs, more danger can ensue. Power tools are like puzzles. If one piece isn’t placed in the right spot, even slightly, it won’t be complete.

 

If you are qualified to perform service repairs: always – I repeat, always – unplug or otherwise disconnect power supplies to your tools before servicing.

 

 

 

Be Familiar with your Power Tool

Be prepared and set yourself up for tool servicing success by familiarizing yourself with the appropriate parts and accessories for your specific tool. Always use identical replacement parts for your specific grinder. And if you’re not sure, check the instruction manual or the manufacturer’s website. Even when performing something as simple as rotating the gear casing, make sure you know and have the correct accessories for the repair.

 

The following steps will explain how to rotate the gear case head on your grinder if that’s the repair you need. This simple procedure can do wonders for lengthening the life of your grinder. But, keep in mind that these steps are for general repairs and may not be applicable to your grinder.

 

1. Remove the guard and flanges from your grinder.
2. Then, remove the screws that attach the gear case to the motor housing.
3. Rotate the gear case head to your desired position. The gear case should not be separated from the motor housing by more than ¼”.
4. Without overtightening, re-install the screws to attach the gear case to the motor housing.
5. Re-install the guard and the correct flanges for the appropriate accessories.

 

Grinder Service Tip #2: Perform Periodic Inspection

It makes sense to go to the doctor when you’re sick. Similarly, you’re quick to try to fix your grinder when it’s not working right. But both people and power tools need periodic check-ups. When inspecting your grinder, check its carbon brushes first. This is because they’re easier to access and damage is easier to spot. Using a bad brush, whether you know it’s bad or not, can lead to costly damage to the armature.

 

If your grinder’s carbon brushes are damaged and need replacing, here’s how to accomplish it:

 

1. Take out the screws in the back of the grinder and remove its housing cover.
2. To remove brushes, wiggle them out or detach them with a screwdriver. Some brushes may have holder caps that are easily removable as well.
3. Use a Q-tip to clean the armature.
4. Replace brushes if they have clear breakage, crumbling, burning, or excessive wear. If your tool’s carbon brushes have a limit mark, replace them if they are worn down to that mark. Also, replace brushes if there is damage to the springs.
5. After the replacement brushes are installed, reassemble the grinder without overtightening screws.
6. After your repair, make sure it’s running great by running the tool for five to ten minutes with no load.

 

It is best to perform periodic inspections of your grinder’s brushes, even if the tool is working fine. However, if your grinder is emitting a burning smell, stalls during use, or produces sparks visible through the cooling vents, brush inspection is even more important.

 

 

Grinder Service Tip #3: Always be Proactive

Picture this: you’ve had your grinder for a couple years now, and you’re beginning to experience difficulty when getting it started up. But once the tool starts up, it runs fine. Your trouble getting it started is annoying, but you don’t think it’s a big enough deal to further inspect the tool. After all, it runs great once it gets going.

 

But this issue is actually a sign of a faulty switch. Even if it seems like a minor annoyance now, the difficulty starting will only get worse until the tool quits working altogether. That’s why you must always be proactive when it comes to the health of your power tools.

 

Take the initiative and inspect your grinder’s switch if the tool has trouble starting or if it has decreased power (these can also be symptoms for faulty brushes). Here is a quick guide to replacing your grinder’s switch:

 

1. First, open the housing and carefully take out the grinder’s parts until the switch is accessible.
2. Remove the screws or fasteners holding the switch down.
3. Keep detailed note of how the switch is wired. You can draw a diagram or snap a picture with your phone.
4. Remove wires from the grinder, and then remove the switch to inspect it more closely.
5. Visually inspect the switch. Look out for heat damage revealed by melted parts or discolored wiring.
6. If there is no visible damage, check if the switch works using a multi-meter. If you want to ere on the side of caution, go ahead and replace the switch regardless.
7. Re-install the wires using the diagram or picture from step three. Be sure the wires don’t get pinched during re-installment. Keep in mind that wiring for the new switch may be reconfigured, so don’t forget to read the instructions.
8. Make sure that all external parts are put back in their proper place, and remove all external tools.

 

By taking steps to determine what is wrong with your grinder at the first signs of equipment trouble, you can extend its life and reduce the risk of serious harm to the tool and to you.

 

Grinder Service Tip #4: Utilize All Your Senses

It’s easy to tell that there’s something wrong with your grinder if it’s not running properly or has decreased power. But your five senses can be helpful indicators of when your grinder needs attention.

 

You already know that an electrical burning smell can mean it’s time to replace your tools carbon brushes. Your eyes are often the first to detect issues too, such as when you see sparks coming off of your power tool. Visible damage to your grinder is a sure sign that something’s not right.

 

Your ears can be invaluable tools too. This gets tricky because using power tools can be loud, and you may even be wearing hearing protection while using your grinder. But your ears can help detect equipment faults that would’ve otherwise not been seen, smelled, or felt.

 

 

For example, worn down bearings create high-pitches screeching noises. Replace noisy bearings immediately. If not, overheating or motor failure can occur. Use these simple steps when replacing the bearings on your grinder:

 

1. Remove the grinder’s side handle and guard.
2. Remove the screws to separate the two halves of the rear housing.
3. Pull any brushes away from the armature. Disengage brush holders if necessary.
4. Remove the separator fan from the back of the armature, depress the spindle lock, and unscrew the fan.
5. Separate the gear case assembly from the motor housing by removing the screws and gently prying it off.
6. Pull the armature from the gear case assembly by hand.
7. Remove the pinion gear by unscrewing the nut and sliding the pinion gear off.
8. Remove the front armature bearing, being careful not to damage the armature.
9. To install the new armature bearing: slide it over the shaft, place a socket onto the bearing over the shaft, and tap a mallet on the socket to move the bearing into place.
10. Replace the pinion gear and tighten the nut that holds it in place.
11. Be sure that all the pieces line up and that the wires don’t get pinched.

 

Utilizing your five senses to detect grinder trouble will make sure its running optimally and that it lasts as long as possible. Engaging all your senses will also keep you alert to the many hazards you should avoid when using a grinder. That said, it’s probably a smart idea to refrain from using your sense of taste!

A Long, Happy Life

Not unlike your childhood hero, grinders are not invincible. But they do boast a great amount of strength and power when looked after properly.

 

Power tools can be a big investment. You want a low-maintenance, efficient tool that you can use for a long time. These useful service tips will help lengthen the life of your grinder so that it’s ready to defeat and task. Do you have any other equipment repair pointers?