In this post you'll learn
One of the questions we get asked the most is about knowing when it’s time for a pneumatic tool repair.
To answer this question, we must first discuss the components of an air tool and how each part can need repair or replacement. We’ve talked about how an air tool motor works, and we have PDF manuals for all the tools in our catalog where you can find exploded views of all of them.
However, to really understand the inside workings of a pneumatic tool, you have to look at how each part interacts with each other.
This gives you an idea of the life expectancy of the tool in terms of wear and tear of each component. Knowing this allows you to get the most out of each tool, use them safely and when the tool needs maintenance.
For this article, we are going to analyze the FUJI Air Tools FA-20-1 F Angle Grinder. This is one of the tools our customers prefer the most, due to its power and versatility even with such a small size.
The Exterior of an Air Tool
Let’s begin with the outside of the tool.
Unlike other less specialized tools, our pneumatic tools exterior is made out of aluminum and steel. This makes housing durable and lightweight. By utilizing aluminum where saving weight is smart, and utilizing steel where strength is required we maximize the lifetime and usability of the tool while enhancing ergonomics and performance.
If you compare the outside of a brand new FUJI Tools angle grinder, against the same grinder but that has been used for years, all you really see is the paint was worn off. Other than that, the tool is not bent, broken or anything that may hinder its proper use.
Air Tool Motor
To talk about the inside components of an air tool, we have to talk about the heart of the tool: the motor.
Parts of an Air Tool Motor
- Rotor Blades (see Exploded View above, part 208)
- Rotor (see Exploded View above, part 207)
- Cylinder (see Exploded View above, part 209)
- Lower plate (see Exploded View above, part 211)
- Upper plate (see Exploded View above, part 210)
- Ball Bearing (see Exploded View above, parts A-01, A-02, A-04)
Once assembled, the rotor blades get attached to the rotor, which once the tool is connected, it will allow the motor to spin and work as intended. Again, we’ve discussed this and other topics in our Pneumatic Tools Learning Center.
What Kind of Repairs Does an Air Tool Motor Need?
The part of the air tool motor that will wear down the most are the rotor blades.
As the rotor blades spin, the friction will eventually wear away the blade, which will decrease its size and ultimately the tool will lose grinding power.
Another thing that can happen is that the rotor blade breaks. Normally this happens due to poor lubrication.
The solution, in this case, is simple, as all we have to do is replace the worn-down rotor blades for new ones.
In the angle head of the grinder, where the grinding wheel goes, there’s the Bevel Pinion (part #423 in the Exploded View image), which is connected to the rotor.
This Bevel Pinion spins and connects with the Wheel Spindle (part #015) to make the grinding wheel spin.
Parts of the Angle Head
- Bevel Pinion (see Exploded View above, part #423)
- Wheel Spindle (see Exploded View above, part #015)
These components allow the grinding disc to spin, letting you do the work.
What Kind of Repairs Does the Angle Head Need?
Since most of the grinding work happens in the friction between the bevel pinion and the spindle, eventually the teeth will reduce in size, and lose tightness. This will make the grinding process more difficult. The solution is to replace these parts.
Safety Tips for the Angle Head
Of course, something important to consider is the safety precautions for the proper use of an angle grinder. Since most of the work happens in the angle head, make sure you follow OSHA’s safety recommendations, so you avoid any possible angle grinder accidents. Make sure you replace the wheel guard when necessary and that it tightens correctly.
The Importance of No Moisture in Compressed Air Used During Operation
One of the most important things you should take into consideration when operating a pneumatic tool is the quality of the compressed air you use.
In the case of pneumatic tools, air quality is measured by the moisture in compressed air.
As a general rule, the inside of the pneumatic tool should be water and moisture free. But properly lubricated with oil at all times.
If the air is wet, the operation of the grinder will be sluggish as the components will jam, stick and rust as a result of the moisture.
The part of the tool that suffers the most from moistured compressed air are the ball bearings.
Water Damage in Air Tools
Water is one of the most damaging elements for your pneumatic grinder.
The easiest way to keep your tools dry is to use the best air tool oil you can find.
Oiling the air tool will repel water and keep all parts working properly.
It’s normal for a pneumatic tool to get wet. This happens often in shipyards, and factories. However, you need to make sure that the tool does not get stored wet. Make sure you dry the tool before putting it away.
Long Term Replacement Parts
We have talked about the air grinder parts that are commonly replaced. There are however, a couple more components that last longer, but eventually need to be replaced.
Lower and Upper Plates
As the rotor turns, the plates will wear down, especially with poor lubrication.
We have said it before, but your pneumatic tools need daily oiling. It is one of the most important good practices you can do to extend the life of your tools.
How Long Can I Expect My Pneumatic Grinder to Last?
We’ll talk about FUJI Tools Pneumatic Grinders here.
If you give the tool proper maintenance, you can expect your angle grinder to last years.
As an average, we usually give maintenance to tools that have been used for 3-4 years, and after maintenance, they can be used another 3-4 years and so on and so forth. Please keep in mind the time we mention is estimated and in no way is a guarantee. The lifetime will depend greatly on many factors as discussed in this and other articles.
Ultimately, replacing the inside components is like getting a new tool for a fraction of the price.
At TFT-Pneumatic we have all FUJI Tool parts available for replacement and repairing. We can do the repairs in-house, or supply the parts to your location if you want to do the maintenance yourself.