7 Types of Angle Grinder Discs and Their Uses. Metal cutting angle grinder
Best Angle Grinder Wheel for metal
Are you looking for the best angle grinder wheel for cutting metal? There are so many good angle grinder wheels out there, that it can be hard to make the right decision.
What makes the best angle grinder wheel for metal?
When buying an angle grinder wheel for cutting metal you want to keep the following things in mind:
- What the grinding wheel is made of – In general, you want to choose a grinding disc that is made from Aluminium Oxide
- Grain concentration – The higher the grain of a grinding wheel the cleaner the cut. For dense materials like metal and steel, you want to use the highest grain possible.
- Durability – A high-quality grinding disc should not wear very fast.
- Price – Price is the final thing you want to keep in mind when looking for a grinding wheel. They may seem cheap but, in the long run, you can save a good amount of money.
Best angle grinder wheels for metal
These are our favorite angle grinder wheels for metal:
DeWALT General Purpose (DW4523)
- Made of aluminum oxide
- High grain concentration
- Very durable
- Best price/quality
Angle grinder wheels come in a million different grains and sizes. It comes as nobody’s surprise that DeWALT is one of the most popular disk manufacturers. They offer a three-year limited warranty on most of their products. Also, they are proven to be one of the best power tool manufacturers. You really can not go wrong with them!
These grinding wheels are ideal to pair with a DeWALT grinder. Read: The best DeWALT angle grinders to find out which are our favorite DeWALT angle grinders.
Specs
This grinding wheel is made of aluminum oxide. A longer-lasting and safer material than some other grinding wheels on this list.
The DeWALT DW4523 all-purpose grinding wheel can be used for all 4 1/2″ inch grinders.
Truswe metal Cut Off Wheel
- Compatible with all 4-1/2 inch angle grinders
- Made of aluminum oxide
- reinforced by double fiberglass mesh
- Great price/quality
Truswe is a less-known brand that specializes itself in grinding disks. For this reason, they produce some of the best quality angle grinding wheels on the market! This grinding wheel in particular is extra thin and super durable. Truswe metal grinding disks are made for 4 1/2 inch angle grinders.
They are made of Aluminum oxide. These fibers stick together making this grinding wheel safer than others on this list. The aluminum oxide will not shatter and will wear less than other materials.
The only thing to keep in mind when buying Truswe grinding wheels is that they come in a pack of 50.
EZARK metal Cut-Off Wheel
- Made of iridium-plated white corundum
- Fast, precise, and clean cutting performance
- Tough abrasive cutting discs
- Decent price/quality
EZARK grinding disks are made of Iridium-plated white corundum. These are in general a bit more durable than standard Aluminum oxide disks.
However, the biggest drawback of corundum is that it has a higher risk to shatter. Therefore we recommend extra safety protection when you are using these grinding disks.
Unfortunately these disks also only come in a pack of 25.
Are you looking for an angle grinder that can be used with these wheels? Check out our guide: Best cordless angle grinders
How to choose the right disc for an angle grinder
Frequently asked questions
Can I use an all-purpose grinding disk for metal?
You can! However, keep in mind that these wheels tend to wear out quicker while grinding metal compared to a dedicated metal grinding wheel.
What started as a passion for power tools has now grown to become our full-time job. With our team of 4 people, we are constantly reviewing the latest tools on the market!
Types of Angle Grinder Discs and Their Uses
Here are seven types of angle grinder discs and their different uses.
According to Handyman’s World:
“Learning to use an angle grinder properly can take a fair bit of practice. Specifically, you’ll often need to practice a variety of techniques for accomplishing the many jobs assigned to an angle grinder.
“Along the way, you’ll likely discover that the default disc on your angle grinder can’t accomplish all of your desired tasks. As such, you’ll also need to set aside some time to learn about the various different types available to professionals and DIYers today.
“In this guide, you’ll learn about seven of the most popular angle grinder discs and their primary uses. This guide will also highlight what many of these discs are made from, which in turn will help you evaluate whether that type can be safely used on your targeted material.
Types of Angle Grinder Discs
Grinding Wheel
“As you can imagine, the first and most obvious angle grinder disc type is the eponymous grinding wheel.
“These wheels are disc-shaped in nature and often feature a ribbed edge that is optimized for removing rough metal edges at a Rapid pace. To that end, these wheels are used in all kinds of metal fabrication jobs that require smoothing down a fresh-cut edge.
“Fresh welds can also be smoothed out with a grinding wheel equipped to your angle grinder.
“However, proper safety precautions must always be taken when working with this type of disc. That’s because its metal composition causes metal-on-metal contact at a Rapid speed. In turn, such contact can cause a serious volume of sparks to spray from any contact point.
“These blades also tend to heat up a lot, so they shouldn’t be touched right after use.
Flap Disc
“Grinding wheels are considered a rather ‘blunt’ method of smoothing down a rough metal surface. As such, they aren’t generally used on jobs that require a person to eventually handle that newly-smoothed edge or surface. Instead, a fabricator may choose to pull out a flap disc.
“These are considered to be the metal equivalent of fine sandpaper.
“As such, a properly utilized flap disc can remove metal burrs, chamfer edges, and take off sharp corners with an enhanced level of precision. Some flap discs can even buff out scratches that occur during the cutting and fabrication process.
“As such, they indispensable for metal craftsmen whose projects are handled by other folks regularly.
Cut-off Wheel
“As you likely already, angle grinders can be used to cut into flat and round metal stock with relative ease. Of course, this can only be accomplished if you have a cut-off wheel equipped to your angle grinder.
“These discs feature a thin profile and a tapered edge that allows them to efficiently slice into forged metal. In practice, these wheels are often able to efficiently cut through bolts, plate metal, rebar, and more – so long as the wheel itself is of adequate width.
“This is because thinner cut-off wheels tend to flex more during a cutting process. This makes them unstable and prone to failure (and sometimes, even shattering) when making deep cuts into thick metal stock. Instead, a thicker cut-off wheel should be used in those instances.
Wire Wheel
“Angle grinders can also be used to accomplish other types of important abrasion jobs if you have the right discs available to you. A wire wheel is one such disc that any good fabricator should have, not least because these wheels are masters when it comes to removing paint and rust from metal surfaces.
“They accomplish this with their sets of metal wire fibers, which are arranged into straight or intertwined bunches to maximize their abrasion potential.
“Keep in mind, though, that wire wheels range greatly in terms of quality. That is to say, try to avoid cheap wire wheels if at all possible. Such discs tend to degrade quickly, which causes the metal wires to break free and fly around.
“Though you should always wear proper PPE when using a wire wheel, these free-flying wires can still pose a risk to yourself and others in your workspace.
Strip Disc
“While a wire wheel can remove paint fairly efficiently, such efficiency comes at a cost. To be specific, wire wheels tend to scuff up the underlying metal surface once the paint has been removed. To avoid that result, be sure to bring a strip disc with you to the job site. These discs are made of a poly-fiber material that can gently, yet firmly remove paint, glue, and epoxy from most metal surfaces.
“If you are removing any of those coatings or adhesives from fiberglass or wood, this type of disc is also a must-have. Otherwise, you’ll find that your wire wheel will do irreparable harm to the surface of either material.
Diamond Disc
“Diamond discs come in several forms. However, most diamond discs on the market today are cutting discs by nature. Not only that, but diamond discs provide top-tier cutting capacity for jobs that involve extra-dense metal stock.
“These discs are able to accomplish those tasks with ease thanks to their impregnated edges, which feature a layer of abrasive diamond shards.
13 Amazing & Useful Angle Grinder Discs
“While they are plenty capable, diamond discs are also fairly expensive. As such, they should be reserved for use only in cutting jobs that truly warrant their use.
Ceramic Sanding Disc
“Ceramic sanding discs are not nearly as common in the professional field, despite their extended service life. In terms of function, ceramic sanding discs can do just about anything a flap disc can do.
“However, they can accomplish those jobs without risking overheating due to their ceramic construction. Better yet, many modern ceramic sanding discs carry a higher sanding capacity than their metal counterparts, making them as efficient as they are durable.
Summary
“Angle grinders are a great multi-purpose tool, regardless of whether you’re a professional fabricator or an amateur DIYer. However, this tool can’t do much more than roughly grind metal without a set of versatile discs available at its disposal.
“As such, anyone looking to make the most out of their angle grinder should invest in at least one of each of the discs described above.
“That way, you’ll be able to take on as many grinding or cutting jobs as your next on-site job requires.”
Can an Angle Grinder Cut Metal or Steel?
There is one question that is quite common on the relevant boards, and that is: “Can an angle grinder cut metal?” The short and simple answer? Absolutely!
In fact, in the sea of hand-held cutting tools for metals, the angle grinder seems to be the most versatile of the bunch for metalwork.
But should you add an angle grinder to your tool collection if you’re regularly cutting metal or keep things simple and cheap with a trusty hacksaw?
Can an Angle Grinder Cut Through Metal?
The best angle grinders are made to cut through harder metals, as well as bricks and or concrete, so you’ll have no concerns when it comes to durability. A good grinder will become a necessity and not a luxury when working with metals or even steel.
Now while you’re average DIYer typically won’t be hacking into dense steel on a daily basis, a quality grinder is certainly the one tool you’ll want in the back of your truck or workshop when endeavoring to make quick cuts into metal materials.
The time it takes an angle grinder to cut through a section of threaded rod in comparison to a hacksaw is startling. Simply put, angle grinders are a HUGE time saver when it comes to cutting metal.
That’s why it comes as no surprise as this particular tool is consistently used by a whole host of different trades, including those folks in the automotive industry, HVAC, plumbing, and many others.
Grinders are primarily utilized for refurbishing and polishing metal materials, so it shouldn’t surprise you that as long as you have the right disc equipped, you can have at it with even stainless steel surfaces.
Note, you shouldn’t go into the process without any precautions. While angle grinders are great for hacking at aluminum or metal stock, there are some safety considerations for beginners to think about.
What Can Be Used to Cut Metal?
Well, if you’re still stuck in the 20th century where power tools like angle grinders aren’t yet the tool of choice, you could leisurely stroll over to the nearest tool shop in your horse and cart and begrudgingly reach for what is known as a “hacksaw”.
Hacksaws can be used for simple DIY tasks like cutting metal stock, and with enough brawn, you should be able to power through something a bit thicker with enough huffing and puffing.
Now, if that doesn’t sound like your glass of Jack Daniels, you could always join the rest of society in the 21st century and make use of an angle grinder for all your future metalworking jobs.
All jokes aside, as long as you’re using the right grinding disc or cutting wheel for your specific grinder (model), cutting and grinding metal materials will be an absolute breeze.
So here’s my compelling case for why you should use an angle grinder for cutting metal like; rebar, angle iron, sheet metal, and just about anything else.
The Mechanism of an Angle Grinder
As we mentioned above, the angle grinder is one of the most popular products on the relevant market. There are a number of different variations of angle grinders; they come in different sizes and with or without a cord.
Personally, going with a grinder of the cordless variety is by far the better alternative in our opinion. Power tools of the cordless variation provide more than adequate power and much greater versatility.
But, whether you use a corded angle grinder or cordless grinder is really irrelevant as either will cut through metal. What you do want to ponder is the size and cutting capacity of the grinder. The most common angle grinder adopted seems to be the 4-1/2 inch model.
If you go with a corded grinder, you should expect a motor with a power capacity of around 9 amps; this will be more than enough to deal with most hard materials.
Although if you’re going the cordless route, don’t go for anything less than an angle grinder utilizing a brushless motor with a 20V Lithium-Ion battery. Cordless grinders are mostly all 4-1/2 inches in terms of capacity and can handle anything from mild metal or steel fabrication, concrete restoration, and or copper pipework.
Apart from all that, a good angle grinder comprises a spinner washer, a comfortable handle, and a protective blade or disc cover. I know, all that sounds nice, but how exactly can you use angle grinders to cut metal? Well, maybe because it can achieve up to 15,000 rotations per minute.
That’s honestly a hell of a lot of force generated by a hand-held power tool. But is it enough to constructively cut cast iron pipe with an angle grinder, and or thick metal/steel? Let’s find out.
How to Cut Metal With an Angle Grinder
Now that we’ve established the concept of an angle grinder for metalwork, it’s time to move on and see what exactly is the best method for chopping metal with a grinder.
We have to suggest that the process is not always the same, as various angle grinder models function differently.
Still, the precautions that you need to take are pretty similar when attempting to cut metal or steel.
Cutting Metal With Angle Grinder – Step-By-Step
- First and foremost, you should ensure that you have all the required tools for this process. Apart from the angle grinder, this includes a power source and a long cable (unless it is the cordless model), along with the earmuffs, safety goggles, C-clamp, and an adequate metal cutoff disc. Last but not least, you should have the metal that you want to cut, set, and ready.
- Once you have all the tools set and ready in place, it is time to prepare the angle grinder for the cutting process. That is done by attaching the appropriate metal cutoff disc and putting the spindle nut in the right place. Also, unless the angle grinder that you are using is cordless, this is the time to plug it into a power source.
- The next step is to fix the metal and mark the cut with a permanent marker. Once you have done that it is time to begin the process. Hold the angle grinder with both of your hands and start cutting with firm precision. Follow the line that you have previously marked and control the kickback ensuring that the cutting is light and smooth.
Note, if there is a need to change the direction, you should do so very carefully without any intense or sudden moves.
This way, you will protect yourself from injury and ensure that the cut remains precise. Once you are done, check for any rough edges and use a flipper to correct these.
What we personally recommend is to finish any cut you commence in its entirety. Doing it halfway and leaving it for another run can only increase the chance of an imprecise and ugly-looking cut.
When you’re tackling thicker metal or steel materials with a grinder, patience is a virtue that you, unfortunately, might have to possess.
Can an Angle Grinder Cut Steel?
It really depends on both the cutting capacity of the angle grinder and the size/type of disc you’re using. Apart from all that, the thickness of the material you’ll be cutting is a determining factor for estimating the potential cutting depth of the steel.
Not only that, cutting discs are available in different thicknesses, and you’ll need to select the right size disc.
But let’s assume you’re using a 4-1/2 inch grinder (like most people) with a flat diamond cutoff blade for cutting either stainless or mild steel. For cutting the stainless steel, you should use a 1mm or 1.6mm iron-free disc.
If you’re cutting thin metal materials like sheet metal, it would be best to use a 1.0mm or 0.8mm cutting disc. Either of these discs will exhibit a cleaner-looking cut and minimize any potential discoloration due to the reduction in blade thickness which will result in less heat transfer.
When using an angle grinder to cut or buff metal or aluminum, utilizing a type of saw lubricant will help preserve the lifespan of the disc and eliminate the possibility of chipping.
How Thick of Steel Can an Angle Grinder Cut?
Now, if you’re going to be chopping thicker, heavier steel such as rebar or structural steel like angle iron, you’ll require a cutting disc between 1.6mm or 2.5mm in thickness. Making use of a thicker blade like a 2.5mm cutting disc for chopping through dense steel does have some drawbacks.
In some cases, the finished cut of your steel workpiece can exhibit signs of discoloration due to the reduced blade speed with the larger disc-equipped. Why is that? Essentially, because of the increase in friction.
So depending on how dense the material is and how clean or cut you’re expecting, you could always consider another power tool for cutting metal.
Either a metal cutting circular saw, or a metal chop saw are two of the usual suspects that pop to mind when precision and finesse are considered a priority when cutting thick, dense steel.
But, if you’re only interest is to make quick cuts where precision and overall appearance are an afterthought, by all means, break out the trusty grinder. Just make sure to use the recommended discs when need be.
In Conclusion
So can an angle grinder cut metal or even dense steel? Yes, it most definitely can. At the end of the day, using an angle grinder to cut metal can be highly effective and extremely safe as long as you have the right equipment and safety tools with you.
If you’ve never operated a grinder before, you’ll need little practice to master the art of effectively slicing and dicing said materials. That is, as long as you’re operating this powerful hand-held tool with the correct cutting disc.
Lastly, make sure that you are safe with full control when wielding a grinder, and always wear the correct protective safety glasses when operating the tool. So all that is left now is to choose the right cutting disc and your material of choice and get cutting metal with ease.
I’m Ray, a lifelong carpenter who’s spent the better part of my life working on construction sites on the West Coast of the United States.
In that time I have literally seen it all within the building industry as a professional contractor.
There’s not much I haven’t encountered over my 30-year career, hence the reason why I’m one of the core contributors at The Tool Scout. Plus, merely writing about work, sure does beat doing actual work. ♂️
The Angle Grinder Wheels You Need for Fabrication
Getting started in fabrication? One of your most useful tools will be your handy angle grinder. You can clean rust and paint, whisk off welding slag, remove metal, and cut stuff. So what wheels should you have in your arsenal and what do they do? We picked out the four best angle grinder wheels for fabrication and take a look at what they do to a piece of steel.
If you’re doing fabrication, you need four types of wheels for your angle grinder. They are the standard grinding wheel, the flap disc, the cutoff wheel, and the wire wheel. If you scroll to the bottom of the article, you can see what each of these wheels does to a piece of rusty metal.
Angle grinder wheels are consumables: they last for a certain amount of time and then they need to be replaced. We’ve experimented with super cheap versions of angle grinder wheels and find that they don’t last as long and don’t hold together as well as versions that cost a little bit more. Here are a few that we’ve tried and liked:
We also like products from Norton, Gemini, and Milwaukee.
The Grinding Wheel
Grinding wheel with 7/8″ arbor hole You can grind with this grinding wheel anywhere on the face or the edge of the grinding wheel.
The Angle Grinder Wheel for Fast Material Removal
The standard grinding wheel is all about fast metal removal. Use the grinding wheel if you want to grind out welds, clean up cuts, and prep metal for welding (since you need bare shiny metal to weld). Of the four wheels, this removes material the fastest. It also produces hot, large sparks. Be sure that the sparks are not hitting anything you care about. Sparks will melt and embed into glass, burn holes in some clothing, and can be a little painful on your skin.
Grinding wheels come in different grits. Just like sandpaper, lower numbers (like 40 grit) are coarse and remove material faster. We will caution that the lower the grit, the larger, hotter, and more painful the sparks are. While this is fine if you’re working at a workbench, grinding under a 4×4 in an awkward position can become very uncomfortable with low grit wheels. Even with typical safety gear, it’s harder to protect your body, your ears, and your eyes from bouncing sparks when you’re jammed under your vehicle, so we suggest a higher grit wheel for that type of work. Stray sparks can easily ricochet and bounce behind a face shield/goggle combination. A higher grit wheel will take a little longer, but it’s safer and more comfortable.
1/4″ Thick Grinding Wheel for Fast Material Removal Standard grinding wheels are ideal for quick metal removal using your angle grinder. 1/4″ thick is pretty standard for most grinding wheels.
Angle grinder standard grinding wheel Pay attention to the wheel diameter when buying grinding wheels. Make sure the wheels you get fit inside your grinder’s guard.
We buy angle grinder grinding wheels 5-10 at a time and that quantity can do most of the typical fabrication projects on a single truck.
Low grit grinding wheels can leave “scratches” in your metal. Really coarse grinding wheels can also leave slight burrs on the edge of your workpiece. We usually clean up these scratches by using a flap disc (below) on the affected areas until the metal is smooth and shiny.
The Best Angle Grinder Wheel for Sharpening Mower Blades and Other Tools
This is also the angle grinder wheel you should use for sharpening mower blades, shovels, and other “blunt” garden tools. It’s easy to remove your mower blade, put it in a bench vise, and sharpen it with your angle grinder. We often finish a blade with a flap disc to make sure it’s smooth.
The Flap Disc is for Finishing
Flap wheel for finer metal sanding Flap discs are ideal when you want to sand metal with your angle grinder. They can lightly chamfer edges, remove burrs, and take the sharp edges off corners.
The Best Sanding Wheels for Angle Grinders
The grinding wheels above tend to gouge the material you’re working on, but a flap disc smooths it out. While the grinding wheel is a hard composite material, the flap disc is basically just overlapping rectangles of sand paper. If you were to run your grinding wheel over an edge on a piece of steel, then you ran your fingernail over that spot, it would catch, since the grinding wheel will push out material at it’s leading edge. This is a burr. Burrs look bad, and can be sharp. they’ll easily cut unprotected hands. The flap disc works great to clean up burrs and shine up gouged metal.
Flap Discs Debur Metal and Take Off Rough edges Use flap discs for finer metal sanding.
Like the standard grinding wheel, these come in different grits. Like sandpaper, the higher grits are for fine work and the coarse grits are for rougher work. We use flap discs all the time for finishing heavy grinding. Flap discs make a huge difference in what your finished piece looks like by removing burrs and scratches, allowing you to put slight chamfers on edges, and also making it easy to take the hard edge off corners.
If the metal part that you’re working on is going to be handled by people we recommend using a flap disc on the exposed edges and corners at the very least to prevent unprotected hands from cutting snagged and cut on burrs and sharp edges.
The Cutoff Wheel is for Metal Cutting
The thin profile of a cutoff wheel The thinness of a cutoff wheel is what makes it cut so easily through metal. This one is.045″ thick.
The Best Angle Grinder Wheel for Cutting Metal
Cutoff wheel with 7/8″ arbor Cutoff wheels with a 7/8″ arbor fit a special shoulder on angle grinders that have a 5/8″-11 threaded arbor.
The cutoff wheel is used for cutting metal. You can use it for cutting out welds, cutting small parts out of sheet or plate metal, or shortening bolts. You only use the edge of the wheel, not the back or front face. In fact, using either face will weaken a cuttoff wheel since they are so thin and the fibers that hold the wheel together are so exposed.
Cutting wheels are considerably thinner than standard grinding wheels. Typically, you’ll use something that’s either 1/8″ or 0.045″ thick. This is 1/2 to 1/4 as thick as a 1/4″ grinding wheel. Because of their thinness and the fact that they only cut at the edge, they can cut metal extremely quickly.
The best angle grinder cutting wheels for metal are also the thinnest. However, the thinner the wheel, the more dangerous they are. Thin cutting wheels flex more easily and thus shatter more easily. If you’re working at a work bench in a comfortable position with a well-positioned workpiece, a thin cutoff wheel is fine. If you plan to work under a vehicle in an awkward position, we recommend using a 1/8″ cutoff wheel that is a little more rigid and will resist shattering if you lose your balance or position.
Also the Most Dangerous Angle Grinder Wheel.
Cutoff wheels are great for fabrication When you need to cut metal, a cutoff wheel on your angle grinder gets the job done quickly.
While the cutoff wheel is very, very handy, it is an extremely dangerous wheel because it’s thin. If you twitch, lose your balance, or otherwise accidentally twist the grinder while using this wheel, it will shatter. The projectiles that fly off could break your nose, damage your hands, hurt bystanders, etc. Keep your face away from this and out of the plane of the spinning wheel.
We have shattered perhaps one or two standard 1/4″ grinding wheels in several years of fab work, but we’ve shattered many cutoff wheels. Lots of fabricators have injuries from not wearing proper safety gear or using cutoff wheels unsafely. One of us even has a nice scar and some grinding material permanently embedded under a fingernail after a shattered cutoff wheel impacted his hand and shattered his fingernail. It’s tough to get everything set up perfectly for using a cutoff wheel on an angle grinder, so do the best you can and wear lots of safety gear.
Safety glasses, face mask, grinder guard, heavy gloves, and no bystanders are essential when you spin up this wheel. We recommend not using a cutoff wheel unless both ends of your material are properly supported. Otherwise, the hanging piece may to pinch the spinning wheel and shatter it. A chop saw should instead be used for some types of work, like shortening lengths of tubing or angle iron.
The Wire Wheel is for Cleaning
Wire back wheel with 5/8″ arbor We like threaded arbors for wire wheels since they make it easy to take the wheel on and off.
The Best Angle Grinder Wheel for Cleaning Paint and Rust
Wire wheels are excellent for removing surface rust and paint. The most abrasive wire wheels have thick, twisted bristles. Straight and thin bristles are much less abrasive, but aren’t aggressive enough if you need to do fast paint and rust removal. In fact, all of the wire wheels we use for our angle grinders are twisted. We only use straight bristle wire wheels on drill attachments and die grinders, and they are all small diameter.
Wire Wheel Front These are thick, twisted bristles, so this will be an aggressive wheel. This is the best type of wire wheel for heavy paint and rust removal.
Like the other wheels, stuff can fly off this wheel at high speeds. the wires occasionally break loose hard enough to stick in your skin. This isn’t so bad, but that should encourage you to wear eye protection. Don’t buy cheap wire wheels for your angle grinder. We’ve tried wire wheels from Harbor Freight, and besides not lasting very long, they will spray you with wire filaments for as long as the wire wheel lasts. Besides being intolerably annoying, this is also dangerous for you and anyone around you since the filaments can so easily pierce skin (and certainly eyeballs).
Real World Tests: What These Grinding Wheels Do
Angle Grinder Wire Wheel Sample
The wire wheel easily took off the rust scale. If you were going to stick weld an emergency repair with 6010/6011 rod, this would probably be clean enough for the weld process. However, you’d want bare, shiny, clean metal for MIG or TIG. A wire wheel with steel bristles won’t gouge steel (although it might “soften” the appearance), but it can gouge softer metals like aluminum or brass.
Wire wheel effect on rusty metal We prefer to have shiny metal for welding, but for a lot of projects a wire wheel will take off enough rust to later do a reasonable paint job.
Angle Grinder Flap Disc Sample
The flap disc is basically worthless for rust removal unless it’s just flash rusting. Scale comes off slowly and we never get to clean bare metal, so this is a pretty pointless use.
Flap wheel effect on rusty metal A flap wheel isn’t sufficient for removing heavy rust. It’s more suited for finer metal sanding and finishing.
Angle Grinder Grinding Wheel Sample
We get right down to bare, shiny metal quickly. This wheel left some pretty heavy gouges in the metal. It won’t look good, but for a functional piece this doesn’t matter. Note that we’ve ground out the pitting caused by the corrosion process. This means that we’ve also reduced the overall thickness of the workpiece in those spots. You generally should not be grinding out 1/8” deep pits on 1/4” material, since you’re reducing the strength of that area to 1/8”. The regular grinding wheel is also great for grinding off mill scale, which is the dull gray “coating” that comes on a lot of commonly available metal.
Grinding wheel effect on rusty metal The grinding wheel is very effective at cleaning rust down to bare metal, but it tends to leave a rough surface and can result in a lot of material removal if you aren’t careful.
Grinding Wheel then Flap Disc Sample
First we used a regular grinding wheel, then ran over it with a flap disc. The workpiece still has a little gouging, but most of the shallow ones were “buffed” out. The finish is much smoother to the touch than the grinding wheel alone. Unlike the grinding-wheel-only sample, this would look pretty good with a coat of paint on it. A production piece with a totally smooth finish (think of a welded plate-style bumper with smooth corners) would likely use a less aggressive grinding wheel (shallower gouging) followed up by a flap wheel.
Using a grinding wheel then sanding flap disc on metal Using the flap disc after the coarser grinding wheel makes the steel much smoother.
Angle Grinder Cutoff Wheel Sample
This is just a straight cut with a cutoff wheel. When through-cutting, you must beware of how the cut piece moves so that it does not pinch the cutoff wheel or kick into the wheel when it falls. For pieces of this size and larger, it is safer to use a chopsaw, bandsaw, or hacksaw (it ain’t so bad!). This wheel is 0.045” thick, so it makes a slightly faster, thinner cut than thicker 1/8” (0.125”) wheels. It’ll also shatter more easily.
Angle Grinder Cutoff Wheel Effect on Metal Cutoff wheels should only be used for cutting. Don’t use the front or back face of the wheel for cutting, or you run the risk of weakening the wheel and causing it to shatter.
ABOUT THE AUTHOR
Mike Johnson
Mike came out of the womb with a Birfield in one hand and a stick of 6010 in the other, ready to weld any piece of trail-busted steel back together. He has wheeled, broken, and modified a variety of rigs, from Toyotas to Jeeps to Fords to Chevies. He likes doing long distance overland travel and would happily spend every night in the bed of a pickup under the stars.