Good Wire Brushes and Die Grinder Attachments

[oldschoolcraft]

I'm planning to do my brakes for the first time by myself soon and on videos I see people using wire brushes and one mentioned a die grinder to clean things up.

I own an M12 fuel right angle die grinder but the only attachments I got so far are Astro Tools 2181 - Double Cut Carbide Rotary Burr Set - 1/4" Shank - Made in China.

The YouTuber "Flat Rate Master" recommended:
OTC 8342 - Brake Hub Resurfacing Kit
Mercer Industries 182020 (high speed version)

I also bought some really cheap wire brushes from HF recently. I dont know what's considered a good quality wire brush and I wanted one to have one hand and the HF was dirt cheap so I picked it up for now.

I asked a while back in general about die grinder attachment and people seemed to like the Roloc system but there was so many options, and I didn't have an immediate use for it, so I shelved the idea and forgot about it until now.

I'm guessing the wire brush is primarily for tight spaces where the die grinder doesnt fit? Or why would I use it instead of the die grinder?

 

[Wamsutta]

Die grinders and wire wheels are not a good combination. Why? Because of the porcupine principle. Wheel wheels are real sensitive to centrifugal force and die grinders spin real fast. The rated RPM will be right on the wire wheel. If you exceed that RPM you getter be wearing safety glasses. A drill would've been a better tool for the wire wheel. For future reference, look at Weiler and Osbourne for wire wheels.

 

[Dave455]

I note you are relatively inexperienced in this, allow me to assist!

Living in the rust prone U.K. I’ve done a good deal of rust cleaning.

If you need to clean rust off anything at any sort of reasonable rate, you need an angle grinder, with typically a “cup brush”, though there are some other styles that work.

Here’s one.


I’ve seen people try to use a wire brush in a drill, and they don’t work. The drill doesn’t spin fast enough.

You have to use one of these on an angle grinder. A 115mm / 4 1/2” grinder will typically spin at something like 11,000 rpm, and you need it turning at that sort of speed to work.

A cup brush has a speed rating, so you need to buy one rated for the speed of your grinder. If you have a 115mm grinder, don’t be thinking you want the biggest brush that will fit, it won’t take the speed. Typically you want a 60mm brush in a 115mm grinder.

Don’t buy one made in China. I have yet to find any that work properly, Even if they don’t shed wires, the cheaper cup brushes tend to be poorly balanced, and will shake you to bits!

The Osborn brushes are great, and I can recommend them 100%. Available from MSC. They are a consumable, and I do a lot of rust cleaning, so tend to buy a few if I see them on a deal. Norton are O.K.

Do not even think of using a wire brush in a die grinder. Unless you are incredibly disciplined, it will shed it’s wires instantly.

The 3M Roloc system is incredibly good, and all of the accessories work well. The best attachments are the “bristle” pads.
These have soft abrasive bristles and are a delight to use. If you’re inexperienced, you can use these in perfect safety as they are so forgiving, but with a bit if practice, you can get an incredibly good finish with these.

Working on a machined but rusted surface, I typically start with a cup brush in a 4 1/2” grinder, then proceed to a Roloc bristle brush in coarse, then one in fine. If I’m working on a machine tool, that’s usually good enough.

Working on a rough casting, such as brake components, I‘d just use the cup brush.

 

[VolvoRyan]

Roloc brake brushes are the bees knees. A regular, not-spinning wire brush is also plenty useful. Plus Brake cleaner.

-Ryan

 

[oldschoolcraft]

I note you are relatively inexperienced in this, allow me to assist!

Thank you Dave!

Do not even think of using a wire brush in a die grinder. Unless you are incredibly disciplined, it will shed it’s wires instantly.

I think they make "high speed" ones that are supposed to remain together and not shoot pieces off at die grinder speeds. Or even with those are they a problem?

And as a beginner I'm not "incredibly disciplined" but I am curious what the proper technique is that an experienced person could achieve eventually, to prevent the wire shedding. is it in the way that you hold it, or the amount of pressure, or taking breaks to avoid the tool overheating?

 

[Dave455]

Thank you Dave!

I think they make "high speed" ones that are supposed to remain together and not shoot pieces off at die grinder speeds. Or even with those are they a problem?

And as a beginner I'm not "incredibly disciplined" but I am curious what the proper technique is that an experienced person could achieve eventually, to prevent the wire shedding. is it in the way that you hold it, or the amount of pressure, or taking breaks to avoid the tool overheating?

Depends on the brush. Depends on the die grinder.

To put things into perspective, a power drill spins at about 2000 r.pm. You can pretty much put any reasonable brush in there.

An angle grinder, 4 1/2” inch, is spinning at about 11,000 rpm. Any quality brush, suitably rated, will withstand this, but a “cup brush” will be splayed out by centrifugal force. This is why, for some applications, you will find more rigid brush’s, but even they struggle beyond a certain rpm.

Most of the small brushes I’ve seen are really made for electric dremel type tools, and they will put up with that use.

If you have a mid quality / 1/4” shank die grinder it’s probably spinning at circa 28,000 rpm. The right brush will withstand that, but I don’t think you will find a “cup brush” that will, only the flat type, and they’re of limited use for rust cleaning.

The correct technique would be to use limited throttle, and perhaps reduced air pressure (assuming it’s an air grinder) but ultimately it’s the wrong tool.

My 1/8 shank Desoutter die grinder is spinning at 80,000 rpm. Any brush of that shank size will disintegrate before it get’s to half speed.

 

[DGersic]

As a rule, I don’t like spinning wire wheels or brushes. Every wire that comes out will embed itself in any exposed skin. That can be painful.

Go to HF and get a bunch of their cheap roloc type fibre disks and the arbor to hold them. They work well enough for most brake work.

Get this kit



or an equivalent. It works well around the lug studs that otherwise get in the way.

A couple of regular wire brushes, hand powered, are good for general cleanup while you’re in there.

Don’t forget your PPE. High speed spinny things are noises and throw off bits and dust. Eye, ear, and breathing protection are all good.

 

[GaryM909]

We used to use these all the time with pneumatic die grinders and they worked great. I did try one with a corded die grinder and it didn't really work that well. Might be okay with a cordless die grinder with variable speed. This Osborn one is only rated for 20,000 rpm. The wires are stainless.

 

[oldschoolcraft]

Thanks again @Dave455 and everyone else for their replies, I have obtained the following since this post:

3M Roloc 2" Base
3M brand 2" discs of various grits
3M brand 2" purple solid course disc

3M Brake Hub Bolt Discs (that are hollow in the middle)
3M Brake Hub Base (that is extended and hollow in middle for the bolts to go into)

Also picked up three different grits of the bristle brushes listed.

Zoro sells all of the above individuals, some of them are just a few dollars each so it wasn't that expensive to get a smattering of higher quality 3M stuff rather than get some HF stuff that might frustrate me.

I was confused by these bristle brushes and how they work, and I put it on my die grinder and when the brush folded outwards like an alien jaw, my eyes went wide in shock!

Speaking of my die grinder, I've had it for a few years but never used it. And couldn't figure out how to get any inserts in it, but I guess the collet insert piece was just jammed in from the factory and I carefully removed it with pliers wrench.

I also came across the Milwaukee die grinder 1/8" collet adapter. I'm not sure which 1/8" Dremel tools I should be using, and perhaps which I should never use in my die grinder. Maybe on speed 1 it's fine? I assume they're rated for much less power.

I'm excited but not sure what uses I'll find for the die grinder. In my reading now, it seems like a lot of people solely use them for brake jobs. I guess I could use it in a variety of household projects, like once I stripped paint from a vintage metal table, and I this would have been a great tool for that. Instead of the 4" angle grinder + wire wheel I used.

I wonder if I can use it for any kind of household cleaning? I did just get some nylon brushes with 1/4" hex shanks and I put them in my impact driver (figured it was close enough of an action to a drill, and it was easier to get to). And it cleaned my dirty bathtub with ease! Not sure if I'd even need to go up to a die grinder for something like that if the nylon bristles are working.

 

[bobg03]

My neighbor swears by Ryobi powered Brushes for cleaning the shower and bath, he probably never heard of a die grinder,,,,

Me, I swear by the great job my housecleaner does bi monthly....

 

[RoninB4]

Would also suggest wearing a face mask. You don't want to be breathing in any of the dust floating around from cleaning the rust or brake pas/shoe material off.

 

[danielbuck]

Die grinders and wire wheels are not a good combination. Why? Because of the porcupine principle. Wheel wheels are real sensitive to centrifugal force and die grinders spin real fast. The rated RPM will be right on the wire wheel. If you exceed that RPM you getter be wearing safety glasses. A drill would've been a better tool for the wire wheel. For future reference, look at Weiler and Osbourne for wire wheels.

I use wire wheels on die grinders all the time. they just need to be rated for the speed.