Diamond Wheel Inc. Diamond bench grinding wheel
Crystal Kut Diamond Grinding & Cutting Wheels
Precision Grinding Supplies Diamond Wheels Chainsaw Wheels Diamond Plating
Diamond Wheel Inc. 7975 Stone Creek Drive Suite 10 Chanhassen, MN 55317
CBN High Speed Steel / Carbide = Diamond
Super Abrasive CBN 5 3/4” Diameter. 7/8” Hole 1/8” Thickness (CS575.8878E) for 1/4325 3/8 Lo Prof (Picco) Pitch 107.00 For use with: Oregon 511/510, 520,620,410 Timbertuff/Upright, Northern, Maxx/Pro-750, Tecomec, Jolly, Efco
Super Abrasive CBN 5 3/4” Diameter. 7/8” Hole 3/16” Thickness (CS575.3878E) for 3/8 404 Pitch 112.00
For use with: Oregon 511/510, 520,620,410 Timbertuff/Upright, Northern, Maxx/Pro-750, Tecomec, Jolly, Efco
Super Abrasive CBN 5 3/4” x 1/4” X 7/8” Hole Chainsaw Raker Wheel (575AC.06548) 112.00
For use with: Oregon 511/510, 520,620,410 Timbertuff/, Northern, Maxx/Pro-750, Tecomec, Jolly, Efco
Super Abrasive CBN 4” Diameter. 7/8” Hole 1/8” Thickness (CS4.8878E) for 1/4 325 Pitch 90.00 For use with: Oregon/Mini, Timbertuff/Bar or Bench Mount, Northern/Compact, Tecomec/Baby
Super Abrasive CBN 4” Diameter. 7/8” Hole 3/16” Thickness (CS4.3878E) for 3/8 404 Pitch 95.00
For use with: Oregon/Mini, Timbertuff/Bar or Bench Mount, Northern/Compact, Tecomec/Baby
Super Abrasive CBN 5 3/4” Diameter. 12mm Hole 1/8” Thickness (CS575.8812E) for 1/4 325 3/8 Lo Prof (Picco) Pitch 107.00 For use with: STIHL Sharpeners Franzen
Super Abrasive CBN 5 3/4” Diameter. 12mm Hole 3/16” Thickness (CS575.3812E) for 3/8 404 Pitch 112.00
For use with: STIHL Sharpeners Franzen
Super Abrasive CBN 5” Diameter. 1/2” Hole 1/8” Thickness (CS5.8805E) for 1/4325 3/8 Lo Prof (Picco) Pitch 103.00
For use with: Foley
Super Abrasive CBN 5” Diameter. 1/2” Hole 3/16” Thickness (CS5.3805E) for 3/8 404 Pitch 107.00
For use with: Foley
NEW Super Abrasive CBN 5-3/4″ Diameter. 5/8″ Hole 3/16″ Thickness (CS575.3858E)
for 3/8 404 Pitch 112.00
For use with: Oregon 700 Series
Super Abrasive CBN 8” Diameter. 1” Hole 1/8” Thickness (CS8.8810E) for 1/4325 3/8 Lo Prof (Picco) Pitch 130.00
For use with: Silvey
Super Abrasive CBN 8” Diameter. 1” Hole 3/16” Thickness (CS8.3810E) for 3/8 404 Pitch 140.00
For use with: Silvey
3/4″ PITCH HARVESTER CHAIN (CS575.6478) 5-3/4 X 5/16 X 7/8 Hole 176.00
For use with: Oregon 511, 510,520,620,410 Northern, Tecomec, Maxx, Jolly, Efco
Click here for Chainsaw information and wheel maintenance instructions. Click here for Diamond Chainsaw Wheels for Carbide Insert Chains.
How To Sharpen Rock Drill Bits With Ease?
Are you tired of using dull rock drill bits? Do you want to improve the performance and longevity of your drill bits? Look no further than learning how to sharpen rock drill bits!
But many Drill enthusiasts need to learn how to sharpen rock drill bits? Fret not, I have the ultimate solution to rejuvenate your drilling game.
Sharpening rock drill bits requires using a grinding wheel and a sharpening jig. The grinding wheel will sharpen the drill bit’s face, and the jig will tilt the bit at a precise angle.
In this article, I’ll guide you through the process, from selecting the right tools to achieving the perfect angle.
Whether you’re a seasoned professional or a beginner, mastering this skill will help you achieve better results on your next drilling project. So let’s dive in and learn How To Sharpen Rock Drill Bits!
What are Rock Drill Bits?
Rock drill bits are specialized tools for drilling into hard materials such as rocks, concrete, and masonry. They are commonly used in construction, mining, and geological exploration.
These bits typically consist of a steel body with a tungsten carbide or diamond cutting edge. The cutting edge is responsible for the penetration and removal of the material during drilling.
Rock drill bits come in various shapes and sizes to suit different drilling applications, and they require periodic sharpening to maintain their effectiveness and prolong their lifespan.
Types Of Rock Drill Bits
- Steel tooth bits
- Tungsten carbide inserts
- Diamond bits
Explanation Of How Each Type May Require Specific Sharpening Methods
Each type of rock drill bit may require different sharpening methods to maintain its efficiency and effectiveness.
- Tri-cone bits: Tri-cone bits have three cones attached to the bit’s head and are mainly used in oil and gas drilling. These bits require a specific type of sharpening method involving a grinder with diamond blades and a grinding wheel to sharpen the cones’ teeth.
- Steel tooth bits: Steel tooth bits are the most common rock drill bits with sharp steel teeth that cut through hard rock.
- Tungsten carbide inserts: Tungsten carbide inserts are used in complex rock formations and are attached to the bit using a welding process.
- Diamond bits: Diamond bits are the most expensive yet effective drill bits in drilling hard rocks. They require specific sharpening methods that involve resetting the diamonds by welding and polishing them diamonds to increase their lifespan and maintain their cutting efficiency.
Therefore, each type of rock drill bit requires distinctive sharpening methods to maintain its effectiveness and prolong its lifespan. Always sharpen your bits regularly to avoid unnecessary expenses and save time during drilling.
Tools Needed For Sharpening Rock Drill Bits
Before sharpening your rock drill bits, you must gather the necessary tools.
- A bench grinder: This tool will help you grind the bits to the desired shape and sharpness.
- A jig or gauge: This tool will ensure the bits are sharpened at the correct angle. You can purchase a jig or gauge online or at your local hardware store.
- Safety gear: Wear safety glasses and gloves to protect yourself from flying debris during the sharpening process.
Safety Precautions To Take Before Sharpening
- Test the wheel for cracks or damages before turning on the bench grinder. Damaged wheels can easily break during operation and cause severe damage.
- Securely clamp the bits before sharpening them to prevent them from moving around.
- Wear the appropriate safety gear, including safety glasses to protect your eyes from any flying debris and gloves to keep your hands safe from sharp bits.
Remember, if you need help with how to sharpen your rock drill bits correctly, consider consulting a professional.
Step-By-Step Guide To Sharpening Rock Drill Bits
Rock drilling is a complex and demanding task that requires excellent tools to perform correctly. In particular, rock drill bits require considerable upkeep and maintenance to keep their effectiveness.
Sharpening rock drill bits is necessary to ensure they operate at their full potential. I will discuss the different methods for sharpening drill bits and the step-by-step guide to make it happen.

To sharpen a rock drill bit, follow some standard procedures to ensure the process runs smoothly and safely.
Step 1: Clean the drill bit.
Ensure the drill bit is clean and free of debris. Any dirt or rocks present underneath the drill’s flutes could cause the bit to bind, leading to improper sharpening.
Step 2: Assess the drill bit.
Look at the drill bit and determine its number of lips or edges. A standard rock drill bit usually has two lips, but some may have three; a higher amount may have more. You must assess the number of edges present before proceeding.
Step 3: Place the drill bit into the jig.
A drill bit jig is necessary to keep the bit stationary while sharpening. Place the jig onto the grinding wheel and adjust the drill bit’s angle according to the bit’s lip angle.
Step 4: Begin the sharpening process.
Start the grinding wheel and slowly bring the drill bit toward it until it contacts the grindstone. Continue sharpening until the grinding wheel removes enough material to point the lip correctly.
Step 5: Alternate sides.
Sharpen one lip, then a short lip on the other side, then back to the first lip and so on. Ensuring they are sharpened evenly and giving extra attention to issues such as flat spots that might require attention.
Step 6: Use the marker.
After tightening your jig’s grips and beginning to sharpen the bit, it’s essential to always use a marker on the drill bit’s lip’s web. The marker will indicate the contact point.
Step 7: Cool the bit and jig.
Remove the bit from the jig and cool it thoroughly. This process is critical if your drill bit is made of high-speed steel to keep the steel from overheating, which can damage the bit.
Step 8: Test the bit.
Once the sharpening process is complete, clean the bit using a cloth. Now, test the drill bit by using it on a metal sheet to see the improvement.
Different Sharpening Techniques For Drilling Through Different Types Of Rock
Bits used in hard rock require a higher number of more extended carbides to help penetrate the more rigid surface.
Sharpening rock drill bits is crucial, and it’s worth emphasizing that not doing it correctly can lead to ineffective drilling that can be dangerous. Follow the steps outlined above to make your sharpening procedure as effective and easy as possible.
Knowing how to sharpen drill bits might make a big difference in how well your equipment performs and ultimately leads to better and more accurate drilling with less downtime and fewer equipment failures.
How To Test The Effectiveness Of Sharpened Rock Drill Bits
If you are a rock drill operator, you know that a blunt drill bit is a nightmare that leads to inefficiencies, costing you a lot of time and money.
But, by sharpening your rock drill bits, you can improve the efficiency of your drilling operation and cut down on expenses.
However, sharpening is only half the job. You need to test your sharpened rock drill bits to ensure that they are effectively sharpened, and this is what this section will FOCUS on.
Here are a few ways to test the effectiveness of newly sharpened rock drill bits:
Check for sharpness
by running your fingers across the tip. If the tip feels sharp, that indicates that the sharpening worked.
Drill a test hole.
Choose a position and drill a test hole with the newly sharpened bit. Assess the time taken to drill the hole and also the overall quality of the hole. A sharpened bit should make a clean and precise hole.
Hammer test
The easiest test to perform is by taking a hammer and tapping the head of the drill bit. A well-sharpened drill bit should make a clear metallic sound, indicating effective sharpening.
Testing newly sharpened rock drill bits is essential to assess their effectiveness and ensure they perform optimally. By implementing these testing methods, you’ll be able to approbate the effectiveness of your newly sharpened bits before putting them to use.
This will save you time and money and improve your overall efficiency in the long run.
The Dos And Don’ts On How To Sharpen Rock Drill Bits?
Remember, adhering to these do’s and avoiding the don’ts will ensure a safe and effective process when sharpening your rock drill bits, maximizing their performance and longevity.
Tips And Tricks For Maintaining The Sharpness Of Rock Drill Bits Over Time
- Avoid drilling in areas with a high water-to-rock ratio, as it causes rocks to soften and wear out the drill bits quickly.
- Always check the weight of your drilling machine and ensure that it is optimized; a heavy drill makes it challenging to maintain the bits’ sharpness over time.
- When operating your drilling machine, ensure that all the parts are well lubricated, as it reduces the resistance and provides a smoother drilling experience.
- After every drill, take some time to clean the bits with a brush and compressed air to remove accumulated rocks and prevent rust formation.
Explanation Of Regular Maintenance Practices
As mentioned earlier, maintaining rock drill bits is critical to the success of your drilling operations.
- Regular cleaning – removing the accumulated debris from the drill bits is essential. Use water and the right type of brush to clean the bits thoroughly.
- Check for wear and tear – examine the bits carefully for any signs of wear or tear. Replace any bits that are beyond repair.
- Sharpen the bits – you can either use specialized grinding tools or take them to a professional to get it done.
- Proper storage – always store the bits appropriately, dry and rust-free.
Keeping your rock drill bits sharp is crucial to your drilling operation’s success. Follow the tips and tricks we have shared, maintain your drill bits regularly, and you’ll ensure that they function correctly over extended periods, maximizing your drilling efficiency.
Frequently Asked Questions Of How To Sharpen Rock Drill Bits?
How Do You Know When A Rock Drill Bit Needs Sharpening?
If a rock drill bit no longer cuts efficiently, it could be dull and needs sharpening.
What Is The Best Way To Sharpen A Rock Drill Bit?
Use a good quality bench grinder, but a drill attachment is ideal for fieldwork.
How Often Should You Sharpen Rock Drill Bits?
It depends on how frequently you use them. Generally, once a month is recommended.
Does The Type Of Rock Affect Drill Bit Sharpness?
Yes, harder rocks like granites wear down the edge of the bit faster than softer rocks.
Can Rock Drill Bits Become Too Sharp?
Over-sharpening can lead to brittle tips and decrease the bit’s lifespan.
In Summary,
Properly sharpened rock drill bits can help you save time and money when drilling. Following the right steps to sharpen them is important to ensure they work efficiently.
Whether working in a quarry, mining site or construction project, knowing how to sharpen your rock drill bits can make all the difference in the world.
Remember to wear protective gear when sharpening your drill bits. To sharpen them effectively, clean the bits, secure them, select the right grinder and grind them, and sharpen the carbide buttons. Following these steps can extend the life of the drill bits and prevent costly replacements.
Sharpening rock drill bits is a crucial skill every expert in quarrying, mining, and construction must have. Take the time to sharpen your rock drill bits properly and reap the benefits of efficiency and long-lasting use.
Hey, I am Shihab Uddin, I’m a huge fan of DIY crafts. My workshop is where I spend most of my spare time, and I’m always working on some project. To that end, I’d like to share some of my knowledge and experience with you in power tools, woodworking, and other specialized materials fabrication.
I will guide you with genuine knowledge that can assist you with deciding whether a drill is appropriate according to your requirements or not. If you want to find the best drill and know which type of drill is most suited for your needs, then I can guide you with my expertise. My passion lies in helping others find the correct products they need at an affordable price.
How To Sharpen Rock Drill Bits With Ease?
Are you tired of using dull rock drill bits? Do you want to improve the performance and longevity of your drill bits? Look no further than learning how to sharpen rock drill bits!
But many Drill enthusiasts need to learn how to sharpen rock drill bits? Fret not, I have the ultimate solution to rejuvenate your drilling game.
Sharpening rock drill bits requires using a grinding wheel and a sharpening jig. The grinding wheel will sharpen the drill bit’s face, and the jig will tilt the bit at a precise angle.
In this article, I’ll guide you through the process, from selecting the right tools to achieving the perfect angle.
Whether you’re a seasoned professional or a beginner, mastering this skill will help you achieve better results on your next drilling project. So let’s dive in and learn How To Sharpen Rock Drill Bits!
What are Rock Drill Bits?
Rock drill bits are specialized tools for drilling into hard materials such as rocks, concrete, and masonry. They are commonly used in construction, mining, and geological exploration.
These bits typically consist of a steel body with a tungsten carbide or diamond cutting edge. The cutting edge is responsible for the penetration and removal of the material during drilling.
Rock drill bits come in various shapes and sizes to suit different drilling applications, and they require periodic sharpening to maintain their effectiveness and prolong their lifespan.
Types Of Rock Drill Bits
- Steel tooth bits
- Tungsten carbide inserts
- Diamond bits
Explanation Of How Each Type May Require Specific Sharpening Methods
Each type of rock drill bit may require different sharpening methods to maintain its efficiency and effectiveness.
- Tri-cone bits: Tri-cone bits have three cones attached to the bit’s head and are mainly used in oil and gas drilling. These bits require a specific type of sharpening method involving a grinder with diamond blades and a grinding wheel to sharpen the cones’ teeth.
- Steel tooth bits: Steel tooth bits are the most common rock drill bits with sharp steel teeth that cut through hard rock.
- Tungsten carbide inserts: Tungsten carbide inserts are used in complex rock formations and are attached to the bit using a welding process.
- Diamond bits: Diamond bits are the most expensive yet effective drill bits in drilling hard rocks. They require specific sharpening methods that involve resetting the diamonds by welding and polishing them diamonds to increase their lifespan and maintain their cutting efficiency.
Therefore, each type of rock drill bit requires distinctive sharpening methods to maintain its effectiveness and prolong its lifespan. Always sharpen your bits regularly to avoid unnecessary expenses and save time during drilling.
Tools Needed For Sharpening Rock Drill Bits
Before sharpening your rock drill bits, you must gather the necessary tools.
- A bench grinder: This tool will help you grind the bits to the desired shape and sharpness.
- A jig or gauge: This tool will ensure the bits are sharpened at the correct angle. You can purchase a jig or gauge online or at your local hardware store.
- Safety gear: Wear safety glasses and gloves to protect yourself from flying debris during the sharpening process.
Safety Precautions To Take Before Sharpening
- Test the wheel for cracks or damages before turning on the bench grinder. Damaged wheels can easily break during operation and cause severe damage.
- Securely clamp the bits before sharpening them to prevent them from moving around.
- Wear the appropriate safety gear, including safety glasses to protect your eyes from any flying debris and gloves to keep your hands safe from sharp bits.
Remember, if you need help with how to sharpen your rock drill bits correctly, consider consulting a professional.
Step-By-Step Guide To Sharpening Rock Drill Bits
Rock drilling is a complex and demanding task that requires excellent tools to perform correctly. In particular, rock drill bits require considerable upkeep and maintenance to keep their effectiveness.
Sharpening rock drill bits is necessary to ensure they operate at their full potential. I will discuss the different methods for sharpening drill bits and the step-by-step guide to make it happen.
To sharpen a rock drill bit, follow some standard procedures to ensure the process runs smoothly and safely.
Step 1: Clean the drill bit.
Ensure the drill bit is clean and free of debris. Any dirt or rocks present underneath the drill’s flutes could cause the bit to bind, leading to improper sharpening.
Diamond Concrete Grinding Wheel for Polishing
Step 2: Assess the drill bit.
Look at the drill bit and determine its number of lips or edges. A standard rock drill bit usually has two lips, but some may have three; a higher amount may have more. You must assess the number of edges present before proceeding.
Step 3: Place the drill bit into the jig.
A drill bit jig is necessary to keep the bit stationary while sharpening. Place the jig onto the grinding wheel and adjust the drill bit’s angle according to the bit’s lip angle.
Step 4: Begin the sharpening process.
Start the grinding wheel and slowly bring the drill bit toward it until it contacts the grindstone. Continue sharpening until the grinding wheel removes enough material to point the lip correctly.
Step 5: Alternate sides.
Sharpen one lip, then a short lip on the other side, then back to the first lip and so on. Ensuring they are sharpened evenly and giving extra attention to issues such as flat spots that might require attention.
Step 6: Use the marker.
After tightening your jig’s grips and beginning to sharpen the bit, it’s essential to always use a marker on the drill bit’s lip’s web. The marker will indicate the contact point.
Step 7: Cool the bit and jig.
Remove the bit from the jig and cool it thoroughly. This process is critical if your drill bit is made of high-speed steel to keep the steel from overheating, which can damage the bit.
Step 8: Test the bit.
Once the sharpening process is complete, clean the bit using a cloth. Now, test the drill bit by using it on a metal sheet to see the improvement.
Different Sharpening Techniques For Drilling Through Different Types Of Rock
Bits used in hard rock require a higher number of more extended carbides to help penetrate the more rigid surface.
Sharpening rock drill bits is crucial, and it’s worth emphasizing that not doing it correctly can lead to ineffective drilling that can be dangerous. Follow the steps outlined above to make your sharpening procedure as effective and easy as possible.
Knowing how to sharpen drill bits might make a big difference in how well your equipment performs and ultimately leads to better and more accurate drilling with less downtime and fewer equipment failures.
How To Test The Effectiveness Of Sharpened Rock Drill Bits
If you are a rock drill operator, you know that a blunt drill bit is a nightmare that leads to inefficiencies, costing you a lot of time and money.
But, by sharpening your rock drill bits, you can improve the efficiency of your drilling operation and cut down on expenses.
However, sharpening is only half the job. You need to test your sharpened rock drill bits to ensure that they are effectively sharpened, and this is what this section will FOCUS on.
Here are a few ways to test the effectiveness of newly sharpened rock drill bits:

Check for sharpness
by running your fingers across the tip. If the tip feels sharp, that indicates that the sharpening worked.
Drill a test hole.
Choose a position and drill a test hole with the newly sharpened bit. Assess the time taken to drill the hole and also the overall quality of the hole. A sharpened bit should make a clean and precise hole.
Hammer test
The easiest test to perform is by taking a hammer and tapping the head of the drill bit. A well-sharpened drill bit should make a clear metallic sound, indicating effective sharpening.
Testing newly sharpened rock drill bits is essential to assess their effectiveness and ensure they perform optimally. By implementing these testing methods, you’ll be able to approbate the effectiveness of your newly sharpened bits before putting them to use.
This will save you time and money and improve your overall efficiency in the long run.
The Dos And Don’ts On How To Sharpen Rock Drill Bits?
Remember, adhering to these do’s and avoiding the don’ts will ensure a safe and effective process when sharpening your rock drill bits, maximizing their performance and longevity.
Tips And Tricks For Maintaining The Sharpness Of Rock Drill Bits Over Time
- Avoid drilling in areas with a high water-to-rock ratio, as it causes rocks to soften and wear out the drill bits quickly.
- Always check the weight of your drilling machine and ensure that it is optimized; a heavy drill makes it challenging to maintain the bits’ sharpness over time.
- When operating your drilling machine, ensure that all the parts are well lubricated, as it reduces the resistance and provides a smoother drilling experience.
- After every drill, take some time to clean the bits with a brush and compressed air to remove accumulated rocks and prevent rust formation.
Explanation Of Regular Maintenance Practices
As mentioned earlier, maintaining rock drill bits is critical to the success of your drilling operations.
- Regular cleaning – removing the accumulated debris from the drill bits is essential. Use water and the right type of brush to clean the bits thoroughly.
- Check for wear and tear – examine the bits carefully for any signs of wear or tear. Replace any bits that are beyond repair.
- Sharpen the bits – you can either use specialized grinding tools or take them to a professional to get it done.
- Proper storage – always store the bits appropriately, dry and rust-free.
Keeping your rock drill bits sharp is crucial to your drilling operation’s success. Follow the tips and tricks we have shared, maintain your drill bits regularly, and you’ll ensure that they function correctly over extended periods, maximizing your drilling efficiency.
Frequently Asked Questions Of How To Sharpen Rock Drill Bits?
How Do You Know When A Rock Drill Bit Needs Sharpening?
If a rock drill bit no longer cuts efficiently, it could be dull and needs sharpening.
What Is The Best Way To Sharpen A Rock Drill Bit?
Use a good quality bench grinder, but a drill attachment is ideal for fieldwork.
How Often Should You Sharpen Rock Drill Bits?
It depends on how frequently you use them. Generally, once a month is recommended.
Does The Type Of Rock Affect Drill Bit Sharpness?
Yes, harder rocks like granites wear down the edge of the bit faster than softer rocks.
Can Rock Drill Bits Become Too Sharp?
Over-sharpening can lead to brittle tips and decrease the bit’s lifespan.
In Summary,
Properly sharpened rock drill bits can help you save time and money when drilling. Following the right steps to sharpen them is important to ensure they work efficiently.
Whether working in a quarry, mining site or construction project, knowing how to sharpen your rock drill bits can make all the difference in the world.
Remember to wear protective gear when sharpening your drill bits. To sharpen them effectively, clean the bits, secure them, select the right grinder and grind them, and sharpen the carbide buttons. Following these steps can extend the life of the drill bits and prevent costly replacements.
Sharpening rock drill bits is a crucial skill every expert in quarrying, mining, and construction must have. Take the time to sharpen your rock drill bits properly and reap the benefits of efficiency and long-lasting use.
Hey, I am Shihab Uddin, I’m a huge fan of DIY crafts. My workshop is where I spend most of my spare time, and I’m always working on some project. To that end, I’d like to share some of my knowledge and experience with you in power tools, woodworking, and other specialized materials fabrication.
I will guide you with genuine knowledge that can assist you with deciding whether a drill is appropriate according to your requirements or not. If you want to find the best drill and know which type of drill is most suited for your needs, then I can guide you with my expertise. My passion lies in helping others find the correct products they need at an affordable price.
The Grind-R-Lap.- A Low Speed Diamond Grinder
Diamond is the hardest known material so it is an obvious choice for grinding and is often used to grind carbide tooling. Diamond wheels are not recommended for grinding HSS because the heat causes the diamond to dissolve in the steel. The way around this is to rotate the diamond wheel slowly to keep the heat low enough so the diamond isn’t damaged. The Leonard Grind-R-Lap (shown above) was the first to commercialize the low speed diamond grinder idea but this idea has been used by others since: Accu-Finish, Cold Grind, Enco, Eskimo, K-K Calamar, SPI, Victory and possibly others. Most of these companies, including Leonard, have ceased making these grinders. Information on these great machines seems to be in short supply so here’s a manual(11mb pdf); the following notes are from examining and using this machine.
The Leonard design is elegantly simple with a surprising economy of parts considering its capability. The diamond wheels are 5″ diameter with a 3″ hole, held to the spindle magnetically; this allows changing wheels/grits in seconds. Most wheels use plating to hold the diamond grit but composite wheels were also available. The 1″ wide wheel oscillates sideways so when a tool is presented to the center of the plated area it actually uses most of the width; this avoids wearing grooves in the diamond abrasive. The oscillation can be stopped to allow grinding certain small features onto a tool.
The grinder is comprised of three major cast aluminum assemblies: the power unit, the case, and the table (shown at right, click to enlarge). The power unit mounts in the case on two bearings, one bearing is seen at the bottom of the power unit. This bottom view shows the sparse internals. The 1740 RPM motor is stepped down about 5:1 by the pulleys to provide a wheel RPM of about 350. The wobbulator is a small eccentric wheel, seen peeking out of its support in the top of the case; the spindle shaft rides on and drives this wheel so its eccentricity causes the grinding wheel to shift side-to-side about once per second. Gravity plus a small spring hold the spindle shaft against the wobbulator wheel.
The table tilt is quickly adjusted via the handle shown on the front of the case, referencing the degree scale on the right side. There are two handles on the right side of the case. The lower handle retracts the table away from the wheel to allow changing wheels. The upper handle is used to disable the wobbulator so small details can be ground easily. The upper handle is also used to relieve pressure on the wobbulator wheel so the spindle shaft doesn’t leave an indent in its rubber surface while parked; just push the lever to the rear prior to turning power off. the lever then supports the power unit away from the wobbulator wheel until the unit is used again.
Diamond wheels are available in various grits from several sources. In addition, a lap can be used where a steel wheel has a brass face attached and diamond paste is used on this to lap cutting tools to a mirror finish. Owners also make steel wheels and glue fine carbide paper to them for a finish similar to a lap. Cutting lubricant, generally water based (but some owners suggest WD-40), is used with the plated diamond wheels to minimize loading and increase wheel life. Diamond wheels can be cleaned with scouring powder, water and a toothbrush.

Grind-R-Lap User Notes
The Grind-R-Lap spins its diamond wheel at low enough speed that it can grind HSS without damaging the wheel through heating. It is also effective on carbide and brazed carbide, where it can grind carbide and the supporting steel without harming the wheel, unlike most high speed diamond grinders.
It is less intimidating to use a Grind-R-Lap than a bench grinder because its low speed steel wheel can’t fail catastrophically. Plus, it is a quiet machine to use and doesn’t spray grit in the immediate area as typical bench grinders often do so it can be kept near other machines for easy access. Grinding residue generally falls down below the wheel and can be cleaned up easily because the feet provide clearance.
While a coarse (260 grit) diamond wheel cuts rapidly, rough grinding is generally done on a bench grinder followed by finish grinding on the Grind-R-Lap. A medium (600 grit) wheel is appropriate following the bench grinder; it leaves a nice finish and generally doesn’t require further honing. When a finer finish is desired then a lap or carbide paper wheel is used. The hollow grind produced by the periphery of a bench grinder wheel can be refined very quickly on the Grind-R-Lap since only the cutting edge need be ground. Table tilt combined with a miter (not shown) allows grinding compound angles on bits.
I noted that after about 3 resharpenings on this unit, bits seem to remain sharp longer between resharpenings. My notion is that sharpening on a bench grinder overheats the cutting edge because there isn’t enough material nearby to conduct the heat away. Resharpening on the low speed diamond eventually removes this slightly damaged HSS so the real HSS characteristics return. Not easy to verify this is what’s going on but my tangential and parting tools seem particularly improved.
Grind-R-Lap Maintenance Notes
The Grind-R-Lap is designed for easy maintenance but this may be neglected because it continues to work well with minimal care. To dismantle, unplug power then tip the unit back onto a towel (to protect the paint). The power unit is easily removed by disconnecting the spring pulling it toward the wobbulator wheel, then remove the rear threaded shaft that supports the power unit. The complete power unit can then be maneuvered off the front support and placed beside the case. the power unit’s cord is long enough to allow this.
The wobbulator wheel can be removed through the front of the case. The grease in the shielded ball bearing is often dried up; it is worth trying a little oil on the shield which may penetrate and free a frozen bearing. This worked on my unit and although it is clearly not perfect it now works fine and will likely go for quite a while because it only runs about 60 RPM. If this doesn’t work out then it is a standard bearing and easily replaced. If the rubber tire on the wheel fails then a new tire must be fashioned since they aren’t available. The wheel is 3/8″ aluminum; the center of rotation is 1/8″ from the wheel center.
The reversible motor needs occasional oiling according to its nameplate. The spindle bearings are shielded and could be replaced if they fail. It isn’t clear how the spindle shaft is retained, it may simply be pressed into the bearings. Removal would be a learning experience 🙂 One source for replacement belts is McMaster-Carr.
The nut on the front power unit support had been backed off and not returned to what I assume is the correct position. This nut rusted onto the threads from liquid used on the wheel so I had to turn it down until the threads would peel off, then run a die over the 1/2-20 threads. I made two nylon nuts for the front and rear supports. Although there wasn’t a nut on the rear support I felt there should be one because the wobble turned the support on its threads rather than pivoting on the bronze bearings. I used these nylon nuts to lock the supports to the case with the idea that the nylon wouldn’t rust in place as the original nut did. Although grease is normally not used on grinders, I added a dab to the bearings supporting the power unit. The front support sets the clearance between the wheel and the table so thread it through until the wheel clears the table when the table is in its forward position. The rear support is spring loaded to accommodate this.
I removed the unit’s table to re-paint; this required tapping the table’s pivot pins out from the inside after removing the power unit. Some versions of the Grind-R-Lap use bolts instead of pivot pins so this can vary. Note that the table springs are right and left handed.
My unit didn’t include a miter so I made a couple miters from scrap. The small one came first and isn’t used much since I made the larger one.
Grind-R-Lap Wheels from Lapidary Disks??
Grinding wheels for the Grind-R-Lap are (2023, Lapcraft) about 120 each so I decided to try converting inexpensive lapidary disks for use with my Leonard grinder. I ordered three 6″ disks, 120/400/1200 grit, offered as a bundle by BangGood for 15; they arrived in 11 days. These disks are about 0.040″ thick steel so they’re reasonably sturdy,
Wheels for the Grind-R-Lap are 5″ in diameter with a 3″ central hole; thickness is about 1/4″ (and they are held on by magnets). I got a 5.5″ by 30″ piece of CRS at a local machine shop and cut 3 pieces 5.25″ long from it. A center punch mark at the center of this rectangular piece was used to scribe a circle 5″ in diameter and this was marked with a Sharpie to make it easy to see. The corners of the rectangle were removed with the bandsaw, much faster and easier than removing all that material with the lathe. The piece was centered in the 4 jaw, drilled to 1″ and then bored to 3.005″, picture at right.
To complete the outside of the wheel it was gripped on the inside of the 3″ hole using the 3 jaw on the Rockwell and the outside was turned down to 5.15″.- the wheels were made a bit over size since there is room on the grinder for this and it allows using more of the 6″ diamond wheels. It takes some time to turn the outside down because it is an interrupted cut and the RPM must be fairly low because the diameter is large. lots of hot chips so I rigged a shield to keep them off my hands during this process. This picture shows the first wheel complete, the second wheel with the central hole, and the raw material for the third wheel. I had read about internal strains in CRS being released during turning but had not seen a serious case until I turned the first wheel: it had a warp of near 20 thou which I had to face off. if you look closely you can see that a small amount of it remains. The other two wheels had only about 5 thou warp so the internal strains varied along the length of this piece of CRS.
This picture shows the completed wheels along with the disks. The disks diameter needs to be reduced to approximately match the wheels. The center of the disks will be left intact since the wheels are thick enough so the disk center will not contact the central hub.
A drive plate replaced the chuck and a piece of cardboard between the diamond side of the disk and the drive plate provided friction. The disk was centered and pressed against the drive plate by a rolling center. A threading tool was used to sort of trepan the disk along with a very thin (0.025″) parting tool to complete the cut. The friction drive was weak so the tool would catch and stop the disk occasionally forcing the infeed rate to be very slow. As the cut started to break through this catching prevented completing the cut but at that point the surface plating was holding the pieces together so it was easy to simply pull the rim off the disk. I used an old, worn file to clean up the cut edge of each disk and then sanded the edge with 100 grit garnet paper. Note the paper towel used to catch most of the chips. Despite this, chips and little diamond glitters were observed on the QCTP and the compound; vacuuming removed most of the fugitive diamond dust but some stuck to oil on the dovetails and had to be wiped off. I avoided using my chip brush lest diamond get into the brush and later get into the works.
The picture at right shows the wheels with the disks reduced in size to fit the wheels. The rims removed may be useful as sharpening stones when cut into short sections. The disks were glued to the wheels by covering the wheels with double sided tape. The wheels were mounted on the 7×12’s 3 jaw chuck via the 3″ hole with about 1/16″ extending out from the jaws. The covering was removed from the double sided tape on the wheel. The rolling center was placed about 1″ from the chuck, the disk was held on the rolling center to center it and the rolling center was advanced toward the chuck until the disk contacted the double sided tape on the wheel. this ensured that the disk was accurately centered on the wheel. The wheel was removed from the chuck and the disk pressed firmly onto the tape. When all 3 wheels were done they were stacked with cardboard between them and a 20 pound weight was placed on top over night to allow the tape to grip fully. All surfaces were cleaned with carburetor cleaner prior to applying the tape.
This is my Grind-R-Lap wheel collection with the new wheels in the top row. The wheels I’ve been using are in the bottom row, at left is a Cold Grind CBN wheel of about 400 grit, center is a diamond wheel of 600 grit, and at right is a worn out wheel converted to a lap by gluing fine carbide paper to it.
Initially, these DIY wheels worked normally. I’ve been using them for a couple years now and they continue to work well. I use water with my GrindRLap wheels; some people use WD40 which might affect the double sided tape. The 400 grit wheel gets the most use.
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