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Bench Grinder Vs Angle Grinder

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15K views 31 replies 14 participants last post by  BigCountry79  
#1 ·
So yesterday I was in the hardware store and found a Steel Grip Bench grinder. It has two wheels on it, and it's 1.1amp and 1/4HP. I have been hearing for a while about angle grinders, and how useful they are. However this was on clearance for $30 and I figured I should snatch it up if it comes in handy. I originally thought that a bench grinder was a stationary version of an angle grinder, but it seems to take totally different wheels. In fact, when I googled information on the difference between bench and angle grinders, I was unable to find anything that really compared the two. I have no idea what the two wheels that it comes with are actually good for, although they are something like 30 grit and 62 grit I think. I tried grinding my steel washers by clamping them in a vice wrench and had some success, but the "softer" aluminum I tried working on was significantly harder to work with because it kept causing the wheels to slow down when I pressed too hard. Probably also a product of the fact that it's so cheap and a low HP, but I have no idea how these things are really supposed to function. I guess the main thing I am asking is, can you use bench grinders for the same thing as angle grinders? Are there special wheels that are designed to cut certain materials on it? I cannot find much of anything for information on that. The default wheels don't have any information other than their grit.
 
#2 ·
Bench grinders can do a lot of things, I have 5 of them for different applications.

Grinding wheels vary by grit, and material they are used for. There are also metal conditioning wheels of various compounds and designs, coarse, to very fine. Wire wheels, and buffing wheels also. Plus you have some grinders that turn slower for special applications like grinding the initial bevel/edge on a cutting tool and not impart too much heat.

As you have found, the difference in a good bench grinder, and a cheap one, is the power.

I won't talk about how many angle grinders I have...
 
#8 ·
Your bench grinder is ...

That grinder is too small and underpowered for all but the smallest tasks. It will NOT grind aluminum well at all, it has the wrong type of wheels. Aluminum clogs most grinding wheels, but an angle grinder has many different types of discs you can get..... silicon carbide, aluminum oxide and zirconia alumina. Here's some tips:
http://www.thefabricator.com/article/finishing/gearing-up-to-grind-aluminum

Some discs:
https://www.metabo.com/us/enus/acce...s/enus/accessories/cutting-grinding/grinding-discs/grinding-discs-for-aluminum/
 
#9 ·
Difference between angle grinder and bench grinder is the speed. Angle grinders run at high RPMs and have universal motors, while bench grinders run at lower speeds and have induction motors. I use my bench grinders for fine work like sharpening chisels, plane irons, and axes, and burnishing handles. Angle grinders are used for rough work like cutting steel and smoothing rough edges.
 
#11 ·
Both tools are pretty completable, they're meant to spin an abrasive disc at high speed to remove metal. An angle grinder is handheld and generally spins faster, it's meant to drive thin cutting discs to cut metal, as well as smaller grinding discs or flap wheels to shape metal. The bench grinder is meant for driving somewhat larger grinding wheels for heavier duty shaping of metal. They're also handy for buffing too.

Both tools have similar uses, but one you move the tool to the workpiece, the other you move the workpiece to the tool

Oh, and it's already been said, but seriously, don't try grinding aluminium, you'll just end up with a clogged wheel and burnt fingers, and a bar of aluminium that's almost exactly the same shape. Files work much better, or a carbide Burr in a die grinder
 
#13 ·
What did you mean here?

Both tools are pretty completable, they're meant to spin an abrasive disc at high speed to remove metal.................
What does this word mean .... and in what context? Spell check didn't catch this?
 
#12 ·
To grind aluminum you need a special wheel Norton makes them under the Gemini brand, don't know why they are different but definitely are regular wheels will clog up and if you keep pushing them they can explode form too much heat, the Gemini wheels stay clean

A die grinder with a carbide burr will also clog up with aluminum, at least mine did when #2 son decided he was going to grind some aluminum, but he was tenacious, he plugged every damn one of them, took an afternoon to dig all the aluminum out of the burrs with a fine scratch awl
 
#15 ·
I've got the usual assortment of angle grinders (4.5 & 7"), die grinders and bench grinders. Each has a use it is better suited for. I'm not sure what a 1/4hp bench grinder is suited for, jewelry? Many different wheels are made for the intended use. For harder metals the harder the metal the softer the wheel is the general way it goes. Also the faster you turn a coarse wheel the finer the finish. Too fine of wheel heats too much. Some wheels break down fast enough that they don't require a lot of dressing. Get yourself a dressing device of some sort when you get a bench grinder. A single point diamond dresser can be used to shape a (G or H) wheel to match a profile. Our 8" Baldor bench grinder is only 3/4hp, but they might be bigger horses.
 
#16 · (Edited)
1/4 hp would be good for sharpening chisels. You can get bench grinder wheels for grinding aluminum.

A right angle grinder lets you take the grinder to the work when the piece is too big to hold up to a bench.

Like a few others, I have different grinders for different jobs. My big grinder weighs over 300 lbs and you won't slow it down no matter how hard you push a chunk of steel into it.
 

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#20 · (Edited)
I would disagree

When grinding welds I grab my Black and Decker Industrial angle grinder and "hog away" and that big brute doesn't even slow down. It will take up to 9" discs. I have other angle grinders from nice 6" Bosch, older Craftsmans to several cheap 4 1/2" Harbor Freight. I also have a pair of vertical Porter Cable grinder/sanders that really are work horses for grinding.

I have a pair of 8" Jet bench grinders, one set up just for wire brushing, the other strictly for grinding. For sharpening drill bits and hand tools with edges I use my 6" X 48" belt sander with various grit belts. It's also good for getting a flat surface on parts to be welded.

They are comparable like a table saw and a circular power saw, in that one is stationary and the other is "portable" or hand held. They both have motors, but the table saw is more likely to have an induction motor and the circ saw will have a universal brush type motor. That's were the similarity ends for me.

Abrasive discs:
http://www.empireabrasives.com/7-x-1-4-x-7-8-grinding-disc-t27/?utm_source=bing&utm_medium=cpc&utm_campaign=Empire%20Abrasives%20Product%20Listings&utm_term=1100913737557&utm_content=Ad%20Group%20%231


Sanding discs:
http://www.harborfreight.com/4-12-in-36-grit-resin-fiber-sanding-discs-5-pc-60231.html
I use my smaller angle grinders with abrasive discs just as much as with sanding discs. I use them primarily on metal to clean and smooth the surface better than the hard discs. Rust removal is made much easier with the angle grinders. Taking the razor edge off a sheared piece of metal is a breeze with the angle grinder and a sanding disc. I use the green 3 M discs which are industrial grade from auto supply and paint shops. http://www.shoplet.com/3M-Abrasive-...05113101922/spdv?utm_source=bing&utm_medium=cpc&utm_campaign=BPA - Items&rtop=1

For sanding wood I use the ROS from Dewalt and Porter Cable with the velcro or hook and loop backing. I use Freud red sanding discs in all the grits from 36 to 220. Because I can attach a shop vac to the exhaust port I can keep the sanding dust to a minimum.
 
#22 ·
I don't see how you can compare either or. Both the bench grinder and the angle grinder have their own purpose which for a particular application one will be better than the other. Both machines you could put an abrasive wheel on but I wouldn't try to strip the paint off of a car with a bench grinder. Likewise if I were sharpening a jointer knife I wouldn't try to sharpening it with an angle grinder.
 
#23 ·
two different tools. I use a bench grinder for shaping small items that i can safely hold in my hand. I use an angle grinder to cut steel, remove rust and paint, do rough sanding, and smooth/debur steel. angle grinder is more useful as you match the accessories to the job. cutting disc to cut, grinding disc to grind, .... you bring the grinder to the work. variable speed is a nice option.
 
#29 ·
CBN are actually different from diamond. Carborundum wheels are tougher and fracture less, but aren't as hard as diamond. This means they wear out slower and last longer.

They look and are used similarly