Shaping wood with an angle grinder

[Jim Dwight]

I've made a few gun stocks and I needed to shape the wood in ways my table saw is not a reasonable tool to use. My bandsaw was useful, of course, but still I needed to shape curves. A rasp would work and a plane sometimes but I am not very patient so I decided to try a flap disc on my right angle grinder. I got one in 40 grit and one in 80 grit. The 40 grit removed wood too quickly, I switched to the 80 grit and was happy with the result. It removes wood very quickly but not so fast it was hard to control.

With these flap discs working so well, I don't see why any body should risk injury with the discs that have chain saw teeth. I've never used one and don't intend to. I think they even have 24 grit flap discs if you need super high speed removal. Seems like these tools are still quite aggressive without a high risk of serious injury.

[glenn bradley]

I'm not a fan of the chain saw wheels. I do use Arbortech wheels with good results.

[Zachary Hoyt]

I use a Kutzall Original disc in my angle grinder to carve soundboards and backs for fiddles and archtop guitars and mandolins, and this winter I am planning to carve a bass with it too. I made one cello several years ago, but the bass is a lot bigger. I haven't tried a flap disc but it sounds handy.

[Doug Garson]

+1 on the Kutzall disc, they remove stock in a reasonably quick manner while still doing it safely. I've also used the flap discs but the Kutzall lasts indefinitely while the flap discs do lose effectiveness over time. Having seen Stumpy Knub's video on his accident with the chain saw type disc I wouldn't consider them and warned my nephew who had bought one. After viewing the video he returned it unused.

[Phillip Mitchell]

+2 of Kutzall. I have also heard good things about the Arbortech turbo plane wheels with carbide cutters, but have not used them.

I was scribing an edge of a piece of wood to a wavy wall once and was using one of the flap discs in an angle grinder and had one of the flaps fly off in mid grind and hit me. Thankfully I was wearing safety glass and ear muffs as the first place it bounced off of was my safety glasses and side of my ear muff…it gave no signs leading up to then that it did not want to stay attached to the disc; it was relatively new and had really not been used for much prior to this happening. . Frightening to say the least. I’m not sure we are talking about the same type of grinder flap disc, but maybe post a photo of what you’re referring to specifically.

[Alex Zeller]

I use a Holy Galahad for shaping but it creates a ton of dust. I normally do it outside. Even then I wouldn't think about using it without a respirator. I've heard that the Turbo Plane cuts faster and makes less dust.

[Bradley Gray]

I have the Arbortech and use it quite a bit. I first bought one of the chain saw wheels but gave it away before using it, too scary. I have used the Arbor tech for carving chair seats and other furniture parts but it's too aggressive for instruments.

[Edward Weber]

I've made a few gun stocks and I needed to shape the wood in ways my table saw is not a reasonable tool to use. My bandsaw was useful, of course, but still I needed to shape curves. A rasp would work and a plane sometimes but I am not very patient so I decided to try a flap disc on my right angle grinder. I got one in 40 grit and one in 80 grit. The 40 grit removed wood too quickly, I switched to the 80 grit and was happy with the result. It removes wood very quickly but not so fast it was hard to control.

With these flap discs working so well, I don't see why any body should risk injury with the discs that have chain saw teeth. I've never used one and don't intend to. I think they even have 24 grit flap discs if you need super high speed removal. Seems like these tools are still quite aggressive without a high risk of serious injury.


It's not about risking injury or which you think is safer, they're just different tools for different jobs.
A flap disc can't cut like a chainsaw wheel and chainsaw wheels doesn't smooth like a flap disc.

[Doug Garson]

Edward, if you don't think it is about safety, watch these videos.

https://www.youtube.com/watch?v=A7xWHEWov8M&pp=ygUZc3R1bXB5IG51YnMgYW5nbGUgZ3JpbmRlcg%3D%3D
https://www.youtube.com/watch?v=x1hf2UILN80&pp=ygUZc3R1bXB5IG51YnMgYW5nbGUgZ3JpbmRlcg%3D%3D
https://www.youtube.com/watch?v=IIQu1e8DGUw&pp=ygUZc3R1bXB5IG51YnMgYW5nbGUgZ3JpbmRlcg%3D%3D

[Edward Weber]

Edward, if you don't think it is about safety, watch these videos.

https://www.youtube.com/watch?v=A7xWHEWov8M&pp=ygUZc3R1bXB5IG51YnMgYW5nbGUgZ3JpbmRlcg%3D%3D
https://www.youtube.com/watch?v=x1hf2UILN80&pp=ygUZc3R1bXB5IG51YnMgYW5nbGUgZ3JpbmRlcg%3D%3D
https://www.youtube.com/watch?v=IIQu1e8DGUw&pp=ygUZc3R1bXB5IG51YnMgYW5nbGUgZ3JpbmRlcg%3D%3D

I really don't need to see how people can injure themselves misusing tools. (especially from a guy who calls himself stumpy nubs)
Correct me if I'm wrong but didn't SN do a safety video after he got hurt?

The point is that these tools are no more or less dangerous than any other tool when used properly. Any tool can be considered dangerous if in the wrong hands and/or not used correctly.
The tool is not the problem, it's the operator.

https://www.youtube.com/watch?v=V8zNgsr5wkE

[Jim Becker]

The greater risk with the saw chain type cutters is that they can go through flesh a lot faster than other available and still effective solutions. That's a big part of the reason that folks (should) wear chaps when using a chainsaw. While it's true that in the end, it's the operator that's responsible, the operator can reduce risk by making good choices before the tool meets the wood.

[Keegan Shields]

The point is that these tools are no more or less dangerous than any other tool when used properly.

False. The design of a tool greatly influences its accident rate. We've all just benefited from the caselaw that requires tool manufactures to be accountable for negligent product design.

A Kutzall or Arbortech wheel isn't amputating fingers without some concentrated effort. The same can't be said for a spinning chainsaw chain.

Then there is the tendency of the chainsaw wheel to catch and jerk, which is not present on the other two designs.

[Jim Dwight]

I don't know how fast the chain saw type blade cuts but my point is just that I was surprised how fast a flap disc removes wood. When relatively new, I agree they wear and the removal rate goes down and at some point they must be replaced. But they are pretty cheap, around $5, so even if you go through a few the cost does not seem prohibitive. For what I do they are plenty fast. Once I tried them I lost interest in the chain saw type.

I am not against chain saws, I own three. But I don't think blades for angle grinders need this sort of tooth to do what I do.

[Prashun Patel]

The chainsaw wheels might be more appropriate for cutting not shaping. Also, without a kickback mechanism, they're a little too dangerous for my liking.

Now, the carbide Kutzall wheels are a different story. They are made for shaping wood. You can still hurt yourself more than a flap wheel, but they last longer and are more aggressive. Also, you don't risk burning.

For a rifle stock a flap disc might be enough. If you have to do a set of windsor chairs, the carbide carving wheels are a worthwhile investment (right after a dust mask and respirator!)

[Edward Weber]

False. The design of a tool greatly influences its accident rate. We've all just benefited from the caselaw that requires tool manufactures to be accountable for negligent product design.

A Kutzall or Arbortech wheel isn't amputating fingers without some concentrated effort. The same can't be said for a spinning chainsaw chain.

Then there is the tendency of the chainsaw wheel to catch and jerk, which is not present on the other two designs.

In broad general terms:
They make chainsaw wheels in many configurations from 4 teeth on up to 22. giving a wide range of removal rate, just like any other wood cutting/abrading tool.
That being said, the design is the design, if used properly, it will cut how it is supposed to cut without incident. The tool's design is not negligent, the operator is responsible for the correct use of the tool.
Negligence is determined if you can be injured while using the tool properly, how it was designed to be used. This is not the case.
If you're going to use one of these tools, you should know what you're doing first, not have it bite you then complain that it's dangerous.
It can be an aggressive tool, depending on tooth count/configuration, wood species, grain, etc.

The OP tried it and determined it wasn't right for him, that's what everyone should do. Determine if it's the right tool for the job, it is after all, a chainsaw.

IMO, most of the injuries occur due to people using much too low a tooth count for what they're doing. This is how most catches occur.
Not understanding how/why they might get kick back
General misuse, one handed use, incorrect guard alignment, etc.
Underestimating the power/speed of an angle grinder.

TIPS:
Start with a high tooth count and work your way down until you're satisfied
Use a variable speed angle grinder
Use a grinder with a paddle switch, (not locked in the on position)
Align the guard properly
Always use two hands
Start slow and practice

[Jim Dwight]

With respect to the safety of an angle grinder with a cutting wheel using chain saw type teeth, there are several factors making them more dangerous than a chainsaw. With a chainsaw the cutting chain is further away from your hands and modern designs have a chain brake to stop the chain if the saw kick backs. Angle grinders do not have brakes and inherently have your hands only a few inches from the blade. They may be appropriate for some things especially the better designs but there are factors that make them more dangerous than a flap disc. My point is just that I think we should try the flap disc first and be sure that it won't do what we want to do. It only costs a few dollars to give them a try.

[andrew whicker]

What is the dust comparison between the spike-y carbide method vs flapper wheels?

Flapper wheels create a LOT of fine dust. Is the other style better?

[Jimmy Harris]

A lot of tools look or seem more dangerous than they are. But far and away the two most dangerous tools out there are the table saw and circular saw. I've seen a LOT of people get seriously injured on those two in my life.

Remember that a tool that LOOKS dangerous and FEELS dangerous will likely command more attention and caution from the user. It's often when we let our guard down because we feel safe that we get hurt. Which is a large reason why I keep cutting myself with hand saws.

To the OP, try a Shinto style saw rasp. They're a good bit faster than regular rasps, but still easy to control.

[Pat Germain]

I use a Kutzall Original disc in my angle grinder to carve soundboards and backs for fiddles and archtop guitars and mandolins, and this winter I am planning to carve a bass with it too. I made one cello several years ago, but the bass is a lot bigger. I haven't tried a flap disc but it sounds handy.

That is one big fish.

[Keegan Shields]

With respect to the safety of an angle grinder with a cutting wheel using chain saw type teeth, there are several factors making them more dangerous than a chainsaw. With a chainsaw the cutting chain is further away from your hands and modern designs have a chain brake to stop the chain if the saw kick backs. Angle grinders do not have brakes and inherently have your hands only a few inches from the blade. They may be appropriate for some things especially the better designs but there are factors that make them more dangerous than a flap disc. My point is just that I think we should try the flap disc first and be sure that it won't do what we want to do. It only costs a few dollars to give them a try.

My thoughts exactly. Adapting a chainsaw chain without the associated chainsaw safety features makes for a poorly designed tool. You're also much more likely to work close to your body unlike a chainsaw, so a jumpy angle grinder/chainsaw disk has a much higher likelihood of burying itself in your torso/arm/leg.

Simply not worth the risk when there are much safer options available.

[Zachary Hoyt]

What is the dust comparison between the spike-y carbide method vs flapper wheels?

Flapper wheels create a LOT of fine dust. Is the other style better?
I don't know if it's better, but it's still very messy. There is some fine and some coarse dust. I was carving top and back plates for a fiddle yesterday and found dust layers flung as much a 5 or 6 feet away. I plan on a few minutes of brisk vacuuming after one of these sessions.

[Prashun Patel]

There is no difference. They both make a TON of dust. The carbide grinder wheel just lasts longer. The carbide wheels act like very coarse sandpaper.

[John Kananis]

So I'll be the square peg here. I personally don't like the idea of an angle grinder, whether it's wheel, chain, etc.

I use a bandsaw, a bowsaw on occasion for the odd stuff and then a spokeshave, rasp(s), chisels and scrapers. Certainly a larger investment and the learning curve of using the individual tools (which most here have to one degree or another) but imho, the work is produced more accurately when you involve yourself at this level.

[Prashun Patel]

"the work is produced more accurately when you involve yourself at this level."

The two are not mutually exclusive.

I use a grinder to hollow out chair seats. Doing a set of chairs exclusively with hand tools (even if you throw in an adze or scorp in there) can be time consuming, and jarring to the body. Different methods of work don't mean more accurate work.

I do like the tools you mention above for safety, noise, and dust reasons (rasps can be dusty, but MAN do they fill a need!).

[Edward Weber]

So I'll be the square peg here. I personally don't like the idea of an angle grinder, whether it's wheel, chain, etc.

I use a bandsaw, a bowsaw on occasion for the odd stuff and then a spokeshave, rasp(s), chisels and scrapers. Certainly a larger investment and the learning curve of using the individual tools (which most here have to one degree or another) but imho, the work is produced more accurately when you involve yourself at this level.

I also am not an angle grinder fan.
When growing up my father used them daily, usually a large craftsman that had a 7" or "9 disc. This was not a "do-all" tool. it was for cleaning up metal, that's it.
It's not been until recently (last 15 years) that the little 4.5" angle grinders became all the rage, with "makers" using them for virtually anything.
There seems to be very little knowledge or concern with regard to safety using these tools, with people making modifications, using them one handed, clamping them in vises and so on.
This is part of the problem when it comes to the chainsaw discs, many people think they're nothing different and start using their grinder as carelessly as usual.
They can be the right tool for the job, hogging out waste or rough carving but for me, that's where it ends.


And, some angle grinders do have brakes for those who didn't know.
Milwaukee has a nice model as an example, https://www.milwaukeetool.com/Products/2889-20

If your going to start using an angle grinder for roughing out or carving wood, do yourself a favor and get a quality one. It's money well spent.

BTW, every tool in my shop can injure you if not used properly, angle grinders are no exception

[Keegan Shields]

BTW, every tool in my shop can injure you if not used properly, angle grinders are no exception

I don't remember anyone saying otherwise. But the risk profile of various tools can differ greatly.

[Mike Cutler]

I would question how many people really have a need for a chainsaw grinder wheel? Most people have little, or no, reason to own an angle grinder at all.
I have only ever seen these things in use at the local fairs. There's always a person that carves animals, out of pine logs with a chainsaw that has one. I've never seen one any where else.
An angle grinder has a very specific purpose, grinding the edges and surfaces of large pipe, or installed pipe, to prepare them for welding, and this is a case ,like many others, where we're trying to make a tool do work it's not really that good at. Yes, they can have a cut off disc installed for small hand held operations, but there are better ways. They're also used a lot in autoody frame repair, but that's a niche of it's own.
The bigger issue I see is not so much personal safety, but the speed of a single speed grinder. A slow speed grinder I can see, but most of the models in a big box store are not slow, or variable, speed grinders. Chainsaws run at a speed designed around the teeth, an angle grinder is spinning much faster.
Other than carving bears, wolves, and Indian heads, out of soft pine logs at the fair, I don't see a use for one in general wood working.
Put it in a slow speed grinder and I can see it would be useful to a very small, fractional, population. I'm not one of those people.
For the record, I do own two angle grinders.

[Zachary Hoyt]

I have a DeWalt angle grinder that I bought about 14 or 15 years ago. I use it with the Kutzall and when I was at the farm I used it often to cut metal when repairing machinery or building something. With the thin cut off wheel and some practice they are pretty efficient for general purpose cutting. I bought a Harbor Freight angle grinder several years ago to use just with the Kutzall so I wouldn't have to move the DeWalt grinder back and forth from the welding/cutting metal area to the workshop, but it died with under an hour of use. People told me they were just as good as the name brand ones, and maybe they are usually, but certainly the one I had was not impressive.

[Edward Weber]

I would question how many people really have a need for a chainsaw grinder wheel? Most people have little, or no, reason to own an angle grinder at all.
I have only ever seen these things in use at the local fairs. There's always a person that carves animals, out of pine logs with a chainsaw that has one. I've never seen one any where else.
An angle grinder has a very specific purpose, grinding the edges and surfaces of large pipe, or installed pipe, to prepare them for welding, and this is a case ,like many others, where we're trying to make a tool do work it's not really that good at. Yes, they can have a cut off disc installed for small hand held operations, but there are better ways. They're also used a lot in autoody frame repair, but that's a niche of it's own.
The bigger issue I see is not so much personal safety, but the speed of a single speed grinder. A slow speed grinder I can see, but most of the models in a big box store are not slow, or variable, speed grinders. Chainsaws run at a speed designed around the teeth, an angle grinder is spinning much faster.
Other than carving bears, wolves, and Indian heads, out of soft pine logs at the fair, I don't see a use for one in general wood working.
Put it in a slow speed grinder and I can see it would be useful to a very small, fractional, population. I'm not one of those people.
For the record, I do own two angle grinders.

I agree;

A chainsaw grinding wheel is a subset of a subset of woodworking. There is a very niche clientele. They are typically running at three times the speed of a chainsaw on a standard single speed grinder.
The other styles, those that cut like rasps and router bit/planers are more widely used and excepted, due to the fact that they are somewhat easier to control. Although all three style each have a unique cut quality of their own. One does not necessarily replace the other.

As far as angle grinders go, I own a 4" and a 4.5", which are primarily used for sharpening mower blades these days. If I need to cut metal, I use a chop saw or a torch as my first options. Torches are quieter, often faster and throw less mess than abrasive wheels/discs, IMO.
In our house, a grinder was for cleaning up metal, not for forming it.

A 4.5" grinder running at 11,000 rpm can be dangerous in the wrong hands, regardless of whet disc or wheel is mounted in it.

I know this thread has strayed and I do apologize but one last thing.
Here is a good video on angle grinders, not directed at woodworkers, just an informative video.
https://www.youtube.com/watch?v=oJRSkBSb5S8

[Mike Cutler]

Edward

No need for apologies, Conversation evolve. If we were all sitting around in lawn chairs with a burger and beer, this is the way the conversation would flow.
A funny story about chainsaw blades in the wrong application
There used to be a string trimmer head that had three lengths of chainsaw blade on it. A coworker was using one around his above ground pool and it caught something and went right into the pool. Right through the aluminum side and liner at ground level.
18,000 gallons of water on the lawn later, he went back to a regular plastic weed whacker string head.:D

[Edward Weber]

https://www.aliexpress.com/i/3256804096232997.html?gatewayAdapt=4itemAdapt

And people think the angle grinder chain is a bad idea :rolleyes:

[Alex Zeller]

I have a Prazi beam saw for my circular saw. It serves a purpose. It's probably the best tool for cutting openings in stress skin panels.

[Doug Garson]

Is this video just a coincident?

https://www.youtube.com/watch?v=o-imZgxAyIE

[Edward Weber]

I would say, maybe? :rolleyes:

Who knows, people use these things like they're toys with little to no regard for safety, more than most other tools in the shop. I would be surprised if the angle grinder injuries weren't piling up.

[Richard Hutchings]

I used them in the past for carving mandolins. My biggest fear was not hurting myself but taking too deep of a cut. I had a lot of respect for that thing and I also had a lot of experience using angle grinders when I was a shipfitter. I can't imagine how someone that works wood regularly wouldn't have the sense or the strength to hold onto the thing. I need to go back and watch Stumpy.

[Richard Hutchings]

After watching his video again, I claim all operator error. He didn't align his body correctly for the cut. I'd much prefer a Kutzal for mandolin making if I wasn't using hand tools.

[Edward Weber]

Here ia a video comparing the various styles of wood carving discs. It's a little old (3 years) but the review is pretty good and still relevant.
https://www.youtube.com/watch?v=mscjKYN5W2w

[Ray Selinger]

I have a full arsenal of metal grinders and sanders . While I have used a chain saw wheel to shape chair backs, I used a rattail angle grinder with the guard, it would be my last choice for shaping gunstocks. If you must use an angle grinder, skip the flap wheels, they are more for polishing than sanding, and use a 36grit sanding disc. It chews wood fast. I like using a spokeshave for gunstocks. Good rasps work wonders, but they are expensive. Make mistakes slowly.

[Jim Dwight]

I didn't use a 36 grit sanding disc but I used both a 80 grit flap wheel on my grinder and a 80 grit disc on my 6 inch sander. The flap wheel removes wood faster in my opinion. My sander is a big Bosch DEVS 1250 that has a "turbo" mode. But I still think the grinder with flap wheel takes material off faster. The 40 grit was too fast in my opinion. Difficult to control. I also found sanding drums in a drill to be handy sometimes. I also have several rasps but I used them the least. I think we all do work somewhat differently so I would not be surprised if others prefer different tools but a 80 grit flap wheel to do the rough shaping followed by the sander with a 80 grit disc to refine the shape and start to get it sanded closer to finish level. The sanding drums are used for both rough shaping and the start of smoothing with different grits on the drums.