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I understand that angle grinders are considered (really) bad for cutting wood.

Would a variable speed angle grinder be any better?

A 10,000+ RPM machine will obviously get caught and go out of control if the line of cutting changes even a bit. Will a machine going at 3-4000 RPM be easier to manage if something goes wrong?

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    Can you clarify what kind of cutter you’re interested in using? There are chainsaw circlets, things that look like sawblades, abrasive cutters… (All of these are terrible, btw; some more so.) Commented Jun 10, 2023 at 11:44
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    Is there a reason to want to use a tool for a job it is not made for? If cost, then hand saws or jig saws cost about the same or cheaper than angle grinders and do a better and much safer job of cutting. Angle grinders should only be used for sanding wood.
    – crip659
    Commented Jun 10, 2023 at 13:33
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    I understand the interest in multi-purpose tools, but, as the answers below should illuminate, this one is likely to injure you. Cheap corded tools can be found on Craigslist or similar marketplaces. Or handsaws are cheap and store nicely. Commented Jun 10, 2023 at 16:47
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    For the occasional use, there's nothing wrong with a character-building handsaw. A cheap new hardpoint panel saw is about $20.
    – Criggie
    Commented Jun 11, 2023 at 1:29
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    "The reason is to have one multi purpose tool instead of a full arsenal, as an occasional user." - Huh? An angle grinder is a multi-purpose tool, just not for the purpose you're proposing. If you're looking to join the sub 10-digit club there are a lot more spectacular ways to achieve that goal and you'd have a non-boring story to boot. Count your fingers, kiss them, and use them to buy an appropriate tool. If a miter saw feels "not multi-purpose enough" then get a circular saw.
    – MonkeyZeus
    Commented Jun 12, 2023 at 15:12

5 Answers 5

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The golden rule in Woodworking is, know where your fingers are before you start to cut, so you don't have to start looking for them afterwards.

That goes double when using the wrong tool. Put the grinder down, walk away, and buy the correct tool for the cutting you propose to do. Even the cheapest saw at Harbor Freight would be a more appropriate solution.

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    The problem is the angle grinder isn't going to stay where you plan to put it. The kickback force will be staggering. The kickback just with my grinder with the wire-wheel cup is considerable. Commented Jun 10, 2023 at 19:55
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    Yeah, this is a new learning for me.
    – ahron
    Commented Jun 14, 2023 at 12:03
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    Just a "little" kick could make for a sore wrist even if it doesn't get loose.
    – gnicko
    Commented Jun 29, 2023 at 0:59
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    @gnicko and that's the best-case scenario. You can also launch the wood or the grinder into yourself.
    – Nelson
    Commented Jun 29, 2023 at 7:43
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Youtube poster "Stumpty Nubs" had a serious accident using an angle grinder with a saw blade. The blade grabbed and the spinning grinder was instantly yanked from his grip and rotated into one of his hands. He describes this incident in online videos.

https://youtu.be/IIQu1e8DGUw

https://youtu.be/x1hf2UILN80

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    Thanks for sharing those resources. Very educative.
    – ahron
    Commented Jun 10, 2023 at 16:49
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    Working from the wrong side, with the guard on the wrong side, having the handle on the wrong side, using the wrong hand, wearing gloves, leaning over the work using a power tool w/o three points of contact, standing in the direction of travel and not ready to let it go safely flying across the room. What could go wrong?
    – Mazura
    Commented Jun 10, 2023 at 20:15
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    Thank you for those links, I'll never again use the angle grinder to cut wood!!
    – Marko
    Commented Jun 11, 2023 at 10:57
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    @user253751 Well, for starters, most angle grinders won't let you attach a standard saw blade and vice-versa, they generally have tabs or some such on them to only fit with attachments they're designed for. Also, circular saws generally have the blade mounted vertically, while grinders have their attachment mounted horizontally, so it's designed for different stress on the tool. Commented Jun 12, 2023 at 18:11
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    @bta plenty of circular saws have a well-placed handle for your other hand. I prefer to use that and clamp the workpiece to something solid (mine is very right-handed BTW, and I'm ambidextrous enough to use some tools, like my jigsaw, left-handed). You're right about vertical cuts with an angle grinder, they're a little awkward and I wouldn't want to be doing them on something as grabby as wood even with both grips held solidly
    – Chris H
    Commented Jun 13, 2023 at 11:04
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Woodworking instruments (including disks that can be mounted on an angle grinder) generally have teeth that in some circumstances can "grab" a piece of wood and fail to cut it trough. Wood has variable and anisotropic properties (and in some cases it also contains long-forgotten nails) that promote such events.

In this case, the instrument with its motor and mainly with its inertia exerts a great deal of force and torque on its support.

When the support is steel or cast iron bolted to a heavy table or to the floor - good. The worst that could happen is that the instrument breaks or some wood piece could fly at considerable speed across the workshop.

When the support is the carpenter's hands, the instrument itself gets wild.

Lower RPM does not in itself make things safer.

At lower RPM the instrument is more likely to fail to cut some harder part and kick back, at the same time the kickback is not much safer.

What can be considered safe, then?

The only thing I personally do with an angle grinder on wood is to cut something small and well-fixed using a disk for metalwork. It has no teeth so it can't easily "grab" something and it also makes the whole process quite inefficient. The disk actually burns its way in the wood.

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    Of course, using a cutting disk on wood also gives a very high chance of having the disk shatter, ejecting razor sharp shrapnel in a variety of directions at very high speed. I was cutting metal with a metal cutting disk in my angle grinder when the blade let go. I'm VERY happy I had the proper guard mounted, was wearing gloves and eye protection. The guard did, at least, prevent pieces from attacking me.
    – FreeMan
    Commented Jun 29, 2023 at 1:06
  • Heat also work-hardens wood, and it'll actually increase the danger.
    – Nelson
    Commented Jun 29, 2023 at 7:46
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Will a machine going at 3-4000 RPM be easier to manage if something goes wrong?

The actual question implies that the act of managing an adverse action may become an easier task. That should tell you the the choice of machine probably was not made wisely.

This begs the question of why? Why is the grinder the tool of choice?

What needs to be accomplished?

What other tools may be a better choice to complete the task.

To answer your question:
Yes, it may be technically easier to handle at a lower RPM, in the event of something going "wrong".

That meaning the bodily injury and accompanying damage to equipment, materials, furnishings, etc. may be to a lesser degree than that experienced if the tool was used at higher RPMs.

** My question to you:**

Is lessening the damage to your body and collateral materials the goal here?

                             OR

Is it cutting some wood?

If it is the latter, please tell us what you are trying to accomplish.

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  • What I'm trying to accomplish is two things - 1) sometimes split some beams or planks of wood without the hassle of using a handsaw and 2) not have to have a full arsenal of tools as only an occasional casual user. If I can find ways to make a grinder acceptably safe (e.g. with less aggressive blades and low speeds) I might consider doing that. If not, I'll probably have to have a circular saw
    – ahron
    Commented Jun 10, 2023 at 16:52
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    If you are limited on tools, sell the grinder and buy a circular saw. Much safer
    – RMDman
    Commented Jun 10, 2023 at 18:13
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    @dakini I completely agree with limiting ones collection of power tools. My electrical toolbox is 16" (small) and electrical is my thing. However, hand tools are the cure for that, not the disease. They're cheap, take little space, and their batteries don't run down. A quality hand saw is indispensable. Commented Jun 10, 2023 at 19:50
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    @RMDman Astounding to use "circular saw" and "safer" used in the same sentence :) No, a quality hand saw is the winner, and there's no question to its safety. Even if you have a 4x6 beam to cut through, it's straightforward. And it's not some bulky, weird limited-use tool you have to then store. Commented Jun 10, 2023 at 19:53
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    @ Harper, yeah, "safer" was entirely relative to the alternative the OP has in mind.
    – RMDman
    Commented Jun 10, 2023 at 20:11
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Angle griders with abrasive blades are fine for cutting wood so long as everything is well secured, and you're not in a hurry.

If you start using cutters in them that can bite into the wood then you're into widowmaker territory.

3000 RPM makes no difference so long as the blade edge is moving faster than you can it's the torque that will get you into trouble, a 3000 RPM angle grinder will probably have more torque and get you into bigger trouble.

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  • I'm not in any hurry. Occasionally I want to split a plank/beam of wood and using a handsaw takes too long.. Using abrasive blades for cutting sounds like a good idea on the face of it, better than saw blades for sure. Might I request a link to a youtube video that shows this, if its not too much trouble to find..
    – ahron
    Commented Jun 10, 2023 at 16:05
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    /skeptical I think the cellulose is going to foul the grinder. Anyway, my 4" grinder's disc is way too small to cut through even a 2x4. So now you're talking a (costly) 7" or 9" grinder that will be utterly uncontrollable. You just won't be able to counter the torque. If the handsaw isn't cutting it like butter, check quality, sharpness and set. Quality handsaws are a dollar at yard sales, as no one appreciates them lol then find a saw shop to sharpen and set (if even needed). Commented Jun 10, 2023 at 19:59
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    I never said it was going to be efficient. to split the occasional plank you're probably better off spending $30 on a cheap circular saw.
    – Jasen
    Commented Jun 10, 2023 at 21:06

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