A variable speed bench grinder allows you to perform a range of tasks you would not perform using single-speed bench grinders. The adjustable speed enables you to tailor the machine to the needs of each job. It is this level of versatility and compelling performance that makes variable speed bench grinders popular among DIYers and professionals.
Comparison Chart
Detailed Product info & Reviews
1. Delta 23-198 8-Inch Variable Speed Bench Grinder
With a variable speed of 2000-3400 RPM, Delta 23-198 can perform a range of tasks including sharpening, grinding, polishing, and buffing. It has a 5-amp motor that operates at 120 volts ideal for handling iron and steel-based alloys.
The machine has a rubber base that prevents vibration especially when operating at high speed. It is also equipped with adjustable tool rest, and a flexible gooseneck allows you to position the workpiece at any angle.
The 36 and 60-grit wheels are designed to handle on coarse and fine grinding applications while the guards allow you to replace the wheels when they are worn out.
Product Highlights
- 5-amp motor
- Uses 40-watt bulb
- Has 36-grit and 60-grit wheels
- Speed of 2000-3450 RPM
- Left-hand tool rest
- Water tray
- Two-piece tool rest
What I Like
I loved the fact that the machine comes with a diamond-based wheel dresser for cleaning the wheels. Apart from the rubber feet, its cast-iron construction reduced vibration significantly. The bit rest fitted on the tool rest came in handy as it helped achieve a suitable working angle regardless of the shape of the workpiece. Additionally, the tool rest is adjustable to allow you to work on the workpieces in different angles while compensating for wheel wear.
What I Don’t Like
I found the bench grinder pretty heavy. As such, I had to designate a particular location for the machine.
What We Like
- Sharpens, buffs, and grinds
- Low vibrations
- Comes with a six-foot cord
What We Don’t Like
- Assembly can be difficult
- The washers are not high-quality
2. Wen 4280 5-amp Bench Grinder
This bench grinder is ideal for DIY projects and professional grinding operations thanks to its 5-amp motor with a variable speed of 2000-3400 RPM. As such, it sharpens drills, screwdrivers, scissors, among other such tools.
The slow speed enhances precision when sharpening tool edges while high speeds improve the rate of material removal. This 8-inch bench grinder has wheels with 80 and 36 grit. What’s more, its cast-iron base is fitted with mounting holes to keep the machine sturdy during operation.
Product Highlights
- 80-grit and 36-grit wheels
- 2000-3400 RPM
- 5-amp variable speed motor
- Flexible work light
What I Like
I found the machine extremely powerful, spending a relatively short time sharpening scissors, dull blades, and screwdrivers. Additionally, it was pretty easy to remove the wheel guards when making wheel changes. The adjustable eye guards also made it easy to angle them in a comfortable position to avoid interfering with the project.
What I Don’t Like
The light only switched on when the wheels rotated. I also didn’t find the tool rest as sturdy for its heavy-duty operations.
What We Like
- Easy to assemble
- Does not vibrate
- Solid construction
What We Don’t Like
- The light depends on the rotation of the wheel to light
3. Porter-Cable PCB525BG Bench Grinder
This is our best pick thanks to the vast range of functional and safety features it has. First, it has a medium-sized 60-grit wheel and a 36-grit coarse wheel for performing a variety of DIY projects, including grinding, tool cutting, and grinding. The wheels can be removed for buffing or when you want to fit a wire wheel.
Secondly, its variable speed ranges from 2000-3400 RPM, which enables it to work on different objects: knives, lawnmower blades, and garden tools. What’s more, the machine is fitted with a two-piece tool rest that enhances precision when working on the tools.
The tool rest is equipped with a groove for easy drill bit sharpening, and it can be adjusted for wheel wear. The machine also comes with a removable water tray for cooling objects during the grinding operation.
You Will Also Love The Product Highlights
- Speed range of 2000-3400 RPM
- Adjustable tool rest
- 40W lamp
- 60-grit and 36-grit abrasive wheels
- Retractable wheel dresser
- Cast-iron base
What I Like
I loved its thin housing profile. It allowed me to work on large, long workpieces like lawnmower blades as I could easily position them on the grinding wheel. The machine also comes with a wheel dresser for reshaping and cleaning the grinding wheel between uses. Additionally, the 40W built-in lamp provided adequate light on my designated working area.
What I Don’t Like
I found the six-foot cable slightly tacky as it compromised on the placement of the machine.
What We Like
- Compact design
- Adjustable work light
- Removable cooling tray
- Retractable wheel dresser
What We Don’t Like
- Wheels are not stable
- Not equipped with locking shaft for changing the wheels
4. Shop Fox W1840
The bench grinder has a unique industrial design ideal for performing heavy-duty grinding applications. With speed ranging from 2000-3400 RPM and a ¾ HP motor, you can perform a range of tasks including sharpening of tools and removal of unwanted material.
The grinder has aluminum oxide grinding wheels. Aluminum oxide is known to hold its form well hence used to grind heat-sensitive alloys and high-speed steels. The chemical also enables the wheels to cut without generating extreme heat.
Additionally, Shop Fox W1840 operates vibration-free thanks to its vast variable speed range.
Product Highlights
- 5/8-inch grinding wheel bore
- Motor speed of 2000-3400 RPM
- 36 coarse grit and 60 fine grit
- Eight-inch aluminum-oxide grinding wheels
What I Like
I loved the large safety eye shields, which made it easy to work on large workpieces. The bench grinder is also fitted with a directional LED light, flexible enough to adjust it to the most comfortable angle.
What I Don’t Like
I found it challenging to assemble the parts. DIYers should consider engaging the help of an expert.
What We Like
- Lightweight
- Stable performance
- The engine remains cool even during heavy use
What We Don’t Like
- Need spacers due to the long-bolt threads on the rod
- Wheels need to be balanced for hassle-free operation
5. Craftsman 9-21154 Bench Grinder
This variable bench grinder is an excellent entry-level equipment. With speed varying from 2000-3400 RPM, it provides adequate power to remove unwanted burs and make smooth polishes. If buying it for DIY purposes, it sharpens tool blades and chisels just as well as professional-grade bench grinders.
Craftsman bench grinder has two six-inch wheels and a wire wheel usually interchanged with grinding wheels to polish or clean workpieces. It also keeps screwdriver bits and other small tools rust-free. Additionally, the equipment has an oversized cast-iron base, which enhanced stability and reduced vibration during operation.
The well-built spark guards and eyeshield keep your eyes protected from flying debris and dust. The bench grinder is also equipped with a built-in light to illuminate your working area while the adjustable tool rest provides you with the much-needed accuracy for bit sharpening.
Product Highlights
- 1/5 HP
- 2.5 amp with 2000-3400 rpm
- Handheld wheel dresser
- Water cooling tray
- Cast-iron base
- Wide eye shields
- Spark guards
What I Like
I particularly loved that Craftsman included a handheld wheel dresser and a water cooling tray in the package. The wheel dressing tool trues up the coarser and 60-grit wheels to expose fresh grains for better cutting action. With the cooling tray, I only needed to fill it up with water to cool the tools while sharpening.
What I Don’t Like
I found it a bit noisy when working at low speeds. Also, the tool rest was somewhat small, making it difficult to work on large items.
What We Like
- Additional features enhance versatility
- Well-lit
- Wide eye shields
- Has a wire wheel
What We Don’t Like
- Small tool rest
- Is noisy at low speed
‘Variable-Speed Bench Grinder’ Buyer’s Guide
Variable speed bench grinders come in different styles to cater to the diverse needs of the users. Machines with a small build are suitable for small jobs, while those with larger ones can handle a range of tasks. While speed is critical when buying a variable bench, it is essential to consider other factors such as:
Speed Control
Most single-speed bench grinders operate at 3400 RPM. This is a pretty high speed suitable for burr and stock removal; and not tasks such as sharpening of tools. Such jobs need a lower rate of 1700 RPM as higher speeds can damage the tools.
A variable speed grinder allows you to adjust the speed to the most suitable one for the job at hand. Some people use a rheostat to control the speed of the single-speed grinder, but this option is only useful for machines using brush type motors. Grinders with induction motors are likely to burn up if operated this way.
Disk Size
Most commercially-available grinders have disk sizes of 6’’or 8’’. If looking for a DIY bench grinder, then the six-inch disk grinder should suffice. Most such machines operate at a speed of 3400-3600 RPM ideal for moderately difficult tasks.
8-inch bench grinders, on the other hand, are suitable for heavy-duty applications and are used with a wire brush and a buffing wheel. They operate a little slower than six-inch grinders, but the wheels last longer and have minimal maintenance requirements.
As such, experts advise buyers to purchase the 8-inch grinder from the onset. They can perform regular sharpening and polishing tasks and save you cash because you don’t have to keep on changing the wheels. Additionally, if looking to create the acute curvature provided by small wheels, you just need to change the 8-inch wheel for one that suits the job.
Application
Look for a bench grinder that allows you to perform a range of tasks, including polishing, buffing, and sharpening. If you want to polish a workpiece, the machine should allow you to attach a buffing wheel. The wheels are available in 6’’ and 8’’ diameters making it easy to find one that will fit the machine.
If polishing metal or wood, look for a wheel with a leather buffing surface. Cotton buffing wheels are ideal for smoothening or polishing plastic surfaces. Also, ensure the wheel provides an adequate working surface.
The Stand
Bench grinders equipped with stands bolted down to the workbench are a good buy. This is because they remain firm during operation, and users can bolt down replaceable bits to create a soft working area.
Grit Size
Grinding wheels come in the coarse 16-24 grit, medium 36-60 grit, and the fine 80-120 grit sizes. Wheels with coarse-grit are suitable for removing burrs and stock, while those with fine-grit are ideal for smoothing surfaces. Buying a bench grinder equipped with the two types of grit (fine and coarse grit) allows you to work on both types of jobs at the same time.
The grit color is another essential aspect to look at, as it indicates the material used. Brown or gray grit wheels are made of aluminum oxide, while green or black grit wheels are made of silicon carbide wheels. Another type is the pink or blue grit wheel made of ceramic material.
Motor Power
Identifying your grinding needs should help you choose a machine with the right horsepower. Bench grinders with a high horsepower can handle tough jobs for a long time and are more durable than those with a low HP.
FAQs
(Q) What is the Best Way to Use a Bench Grinder?
(A) First, perform a safety check to ensure the machine sits securely on the workbench. Then, secure the tool rest is set firmly, leaving 1/8-inch space between it and the wheel. The area should be free of debris and provide room for you to push the object for sharpening back and forth. Also:
- Ensure the guards are secure
- Maintain a quarter-inch wheel exposure with the movable guard or tongue guard
- Ensure the wheels have blotters on either side
- Ensure the wheels fit securely when mounting. Replace a loose wheel
- Spin the wheels manually before plugging it to the power source to ensure it spins freely
- Tighten the nuts before turning on the machine
(Q) How Do I Reduce the Risk of Overheating the Machine?
(A) Friction produced by the material, and the grinding wheel can cause the wheel to overheat. Using the rough grit wheel at slow rotation speeds reduces overheating. Also, consider dipping the metal tool in water if it begins to get too hot. A container of pre-warmed fast-quench oil comes in handy when sharpening metal objects as it prevents cracking.
(Q) Which Accessories should You Use with a Bench Grinder?
- Wire brush wheel brush: It is ideal for removing paint, corrosion, and burns. The tool also comes in handy when tidying up the surface
- Wheel dresser: It helps you clean and dress wheels to create an even grinding surface. The best wheel dresser should take the least time to get the job done. It also comes in handy when removing metal buildup
- Buffing wheels: They are ideal for finishing surfaces prone to marring or scratching. They provide different finishes from light material removal to mirror-like polish hence vary depending on the application and the workpiece. Thus when buying buffing wheels ensure it has the properties and features you need
- Pedestal stand: Placing the machine on an ordinary table causes the grinder to vibrate, which creates clutter. With a cast-iron or steel stand, you are sure to keep the bench grinder sturdy for effective performance
(Q) How Often Should I Clean or Dress the Bench Grinder?
(A) It depends on how often you use the machine. A thorough cleanup twice a year should be enough. When it comes to dressing, it should be done regularly. Regular light dressings are better than heavy dressings. Here are a few steps to guide you when dressing wheels:
- Inspect the grinding wheels and the dressing tool for cracks
- Place the tool rest close (1/16-inch space) to the grinding wheel
- Spin the wheel manually to check for stability
- Turn on the grinder at full RPM and position the dresser off the center towards the end of the wheel
- The process should leave the wheels dressed and trued enough to expose the sharp abrasive grains on the workpiece
(Q) What should you avoid when using a bench grinder?
- Avoid switching it on before making sure the machine and the wheel are stable
- Avoid over-tightening the nut on the wheel. The excessive pressure may cause the wheel to crack
- Avoid using an improperly fitted wheel
- Avoid leaving the grinding wheels in standing liquid. The liquid causes balance problems
- Avoid grinding the material on the side of the wheel
Conclusion
Delta 23-198 makes a great bench grinder for heavy-duty applications. Its 5-amp motor allows it to handle a range of tasks without overheating the machine. However, the machine is a little pricey for simple DIY tasks making the Craftsman 9-21154 variable speed bench grinder a better pick. Its 2.5-amp motor should keep your home tools sharp; and the best part is it is pretty affordable.
