UFO identified

[Markw]

Do NOT turn the wheel around!!!!

By doing this you flex the brush in the opposite direction and fatigue the wire causing them to break off - next thing you know you will be coated in the little wire bits. :eek:

Once a wire brush is bent, leave it that way

[Shedhand]

Do NOT turn the wheel around!!!!

By doing this you flex the brush in the opposite direction and fatigue the wire causing them to break off - next thing you know you will be coated in the little wire bits. :eek:

Once a wire brush is bent, leave it that way

OK. Thanks. I won't turn the wheel around. I did wonder about the wisdom of doing so.
Cheers

[JDarvall]

Do NOT turn the wheel around!!!!

By doing this you flex the brush in the opposite direction and fatigue the wire causing them to break off - next thing you know you will be coated in the little wire bits. :eek:

Once a wire brush is bent, leave it that way

:confused: ....Well, this is confusing....never had the problem of it introducing too much wear. Used wire wheel in this way for years.

Just recently, I've setup a workhead with a reversable motor, with this idea in mind....ie. so I can, with just a flick of a switch reverse the motor, without having to unbolt the thing and flip.

In fact its remember reading about advice given from a wire wheel manufacturer...saying its best to reverse direction. Flexbro ?...

How hard do you push into the wheel Mark ? ...

[Markw]

:confused: ....Well, this is confusing....never had the problem of it introducing too much wear. Used wire wheel in this way for years.

How hard do you push into the wheel Mark ? ...

Irrespective of what the manufacturer might say, especially if they have a vested interest in reducing the service life of a product:

When a wire strand permanently bends in a wire wheel, it bends at the point just above the connection to the wheel hub. When you permanently bend it from operating in the reverse direction it will bend in the same place.

The wire used to construct these wheels are generally bright mild steel [BMS] (denoted by the amount of rust forming on the wire) or brass coated BMS or on rare occassions a fully brass wire. In the case of BMS bending the wire introduces fatigue as will any permanent continual movement past the elastic limit of the material. As for brass any permanent continual movement will cause work hardening of the material and ultimately failure (breakage of the wire).

As to how hard do I push against the wheel, generally not sufficient to cause noticable slowing of the machine where you would back off to allow it to reach max speed again.
This is like asking how long is a piece of string??????????

BTW Buffing wheels are for buffing (polishing), not metal removal.

[JDarvall]

Irrespective of what the manufacturer might say, especially if they have a vested interest in reducing the service life of a product:
.

I agree that happens a lot. But, to the point that they'll risk injuring somebody through bad advice? Your impleying that reversing the wheel will break them all off and cover user in broken wire....ie. very dangerous you say ! yes ?
If this was a major concern, I doubt the company would actually advise people to do it.

I found the documentation, and taken some photo's. So, basically, your saying that everything in the first photo is crap, right ?

When a wire strand permanently bends in a wire wheel, it bends at the point just above the connection to the wheel hub. When you permanently bend it from operating in the reverse direction it will bend in the same place.

The wire used to construct these wheels are generally bright mild steel [BMS] (denoted by the amount of rust forming on the wire) or brass coated BMS or on rare occassions a fully brass wire. In the case of BMS bending the wire introduces fatigue as will any permanent continual movement past the elastic limit of the material. As for brass any permanent continual movement will cause work hardening of the material and ultimately failure (breakage of the wire).

As to how hard do I push against the wheel, generally not sufficient to cause noticable slowing of the machine where you would back off to allow it to reach max speed again.
This is like asking how long is a piece of string??????????
.

Look at the second photo. Talks about how pressuring the wheel too hard is a real no no. Thats why I was asking how hard you press the wheel. Cause, I don't see a problem with reversing the wheel, unless you press so hard, that the wire does bend significantly. Do you see where I'm coming from ?

To back this up, for myself at least, I've got plenty of personal experience, thats seen no difference in wear when reversing a wheel.

The advantages I feel are noticable in wheel reversal. Suddenly, your wheel is cutting like new again, when you reverse the wheel,,,,

Actually, in fact, what I think tends to happen when using a wheel thats bluntened (cause its been used in the same way all its life) is that one is more inclined to push into it harder, cause, it JUST AN'T WORKING, too ####ing blunt !...and it bends over more and more in the same direction, until your right, if you reverse the thing then, it will be too bent, and possibly dangerous.

The trick is I think, to reverse the wheel as often as possible and to keep as light a touch on the thing always to avoid this over bending occuring.

Look, there's pages and pages of detail on brushes, safety, speed, do's and don'ts....all sorts of details from these companys. 3rd picture. Hard to believe they'd stuff up something as simple as .....telling their customers that its good to reverse wheels,,,,so, uno, they end up injuring themselves. IMO.

BTW Buffing wheels are for buffing (polishing), not metal removal.

:confused: ...I'm confused again Mark. So what ? What I was saying , was, you have to drag your item accross the wire wheel in the same way you have to drag your item accross a buffing wheel ? Thats all I said. I didn't mention anything about metal removal. I don't know what you thought I said. ....PUT ME STRAIGHT MARK !....

[JDarvall]

Sorry, I put the wrong photo in......I should have put this photo instead of 2nd picture above.

[Shedhand]

I inherited a 1/2 HP 6" grinding wheel and put a new grinding wheel and wire brush on it. When I turn it on it runs beautifully and quiet. But it scares the crop outta me. It seems to go a million miles an hour. I s'pose its safe. Any advice Tripper?:confused:
Cheers

[BobL]

I inherited a 1/2 HP 6" grinding wheel and put a new grinding wheel and wire brush on it. When I turn it on it runs beautifully and quiet. But it scares the crop outta me. It seems to go a million miles an hour. I s'pose its safe. Any advice Tripper?:confused:
Cheers

Did you check if the RPM rating of the grinding wheel and wire brush are greater than that of the grinder motor? A mate of mine put a big hole in the side of his shed by not checking. I always have in mind the medical program about this guy whose grinder wheel exploded and it took away his LHS jaw, teeth and cheek bone and part of his eye socket. He lived and they reconstructed his facial bones using bits of rib etc amazing stuff - the bone surgey had a lot of woodworking aspects to it, trimming, planning drilling etc.

Oh and have you seen the dude on the web who shatters CDs by revving them up with a dremel? He's doing this in his apartment with the full safety kit of board shorts and wrap around sunglasses!

[Markw]

I agree that happens a lot. But, to the point that they'll risk injuring somebody through bad advice? Your impleying that reversing the wheel will break them all off and cover user in broken wire....ie. very dangerous you say ! yes ?
If this was a major concern, I doubt the company would actually advise people to do it.

I found the documentation, and taken some photo's. So, basically, your saying that everything in the first photo is crap, right ?

To back this up, for myself at least, I've got plenty of personal experience, thats seen no difference in wear when reversing a wheel.

The advantages I feel are noticable in wheel reversal. Suddenly, your wheel is cutting like new again, when you reverse the wheel,,,,

Actually, in fact, what I think tends to happen when using a wheel thats bluntened (cause its been used in the same way all its life) is that one is more inclined to push into it harder, cause, it JUST AN'T WORKING, too ####ing blunt !...and it bends over more and more in the same direction, until your right, if you reverse the thing then, it will be too bent, and possibly dangerous.

The trick is I think, to reverse the wheel as often as possible and to keep as light a touch on the thing always to avoid this over bending occuring.

Look, there's pages and pages of detail on brushes, safety, speed, do's and don'ts....all sorts of details from these companys. 3rd picture. Hard to believe they'd stuff up something as simple as .....telling their customers that its good to reverse wheels,,,,so, uno, they end up injuring themselves. IMO.


:confused: ...I'm confused again Mark. So what ? What I was saying , was, you have to drag your item accross the wire wheel in the same way you have to drag your item accross a buffing wheel ? Thats all I said. I didn't mention anything about metal removal. I don't know what you thought I said. ....PUT ME STRAIGHT MARK !....

First is first:
I am not stating that they give "bad" advice intent on injury, remembering that a wire wheel will always shed wires to some extent irrespective of how it is used and therefore the possibility of injury is always present. Only the type and quality of PPE prevents injury in this process. What I may have phrased incorrectly was that IMO, their advice may not lead to the longest service life of the product.

Reversing a wheel will not break "ALL" the wire strands off but increase the proportion shed depending on the bend radius and number of bends exceeding the elastic limit of the wires achieved by the operator. This is basic theroy - Strength of Materials - 2nd year Mech Engineering.

As to the documentation, I too have more than 30 years of both trade (heavy diesel plant) and engineering (Mech) to which I was taught not to turn a wheel around and why as stated previously. Whilst I credit the manufacturer with his documentation, I have my own understanding of how the world rotates and when the wheel refuses to polish further I either change process because what I'm doing is wrong or replace the wheel because its worn out (getting low on wires doesn't happen very often to me).

As you stated that the wheel would seem to be rejuvinated on reversal, my assumption would be that the wires were already flattened to some degree and that by reversing the wheel you are in fact striking the work piece with the point of the wire possibly perpendicular to the work (hard to explain without lots of text or a white board). Think of a circle drawn in 2 halves with arrow heads on each half. BTW if the point is striking the workpiece, it would be transmitting a compressive shock-load axially along the wire strand and as metals cannot compress this can only increase the fatigue of the wire at either the point of bend or point of connection to the hub.

With regard to metal removal, I wasn't accusing you of using a wire wheel in this fashion but using a broad statement to ensure that members realise that the wire wheel is a buffing style wheel for altering the surface finish of an object and not to be confused with a grinding or material removing process. Many a time I have seen people using a wire wheel and when the wheel does not polish or clean fast enough they push harder into the wheel. Instead perhaps the item should of been sanded or sandblasted or a dozen other processes first before buffing was attempted.

In closing you did ask me how hard do I push into a wire buff and the reply containing the issue of metal removal was to indicate that I did know the purpose of a wire wheel and not as a jibe against you. Don't be so sensitive

[Markw]

Did you check if the RPM rating of the grinding wheel and wire brush are greater than that of the grinder motor? A mate of mine put a big hole in the side of his shed by not checking. I always have in mind the medical program about this guy whose grinder wheel exploded and it took away his LHS jaw, teeth and cheek bone and part of his eye socket.

Always always stand to the side of a bench grinder or for that matter any high speed fixed rotational tool as it achieves operating speed. As it gets there it goes through the harmonic points where any out of balance coupled with any damage may cause a wheel, shaft, bit, blade to explode, shear fall apart or generally become extremely danger in close proximetry.

You only need to think what would happen if:

[jaspr]

Thanks Markw

Grinders scare me - I always approach with trepidation - and mine only goes round at 1450 rpm!

Standing to the side as it comes to full speed is not something I have considered for the grinder. On the other hand, I try to never stand in front of the table saw - ever.

I'll do this with the grinder in future. Green one on its way.

jas

[Shedhand]

Did you check if the RPM rating of the grinding wheel and wire brush are greater than that of the grinder motor?

I did that and both the wire wheel and the grinding wheel ar rated at greater than the motor. Still seems damn scary though. Guess I'll get used to, then complacent, then feed my hand into it. :eek:

Oh and have you seen the dude on the web who shatters CDs by revving them up with a dremel? He's doing this in his apartment with the full safety kit of board shorts and wrap around sunglasses!

Must be an unemplyed dopehead with a deathwish.:mad::eek:

[Waldo]

G'day Shedland,

Looks like Zed's been in your dunny pinching all the paper again. Ain't he toilet trained yet?

[JDarvall]

In closing you did ask me how hard do I push into a wire buff and the reply containing the issue of metal removal was to indicate that I did know the purpose of a wire wheel and not as a jibe against you. Don't be so sensitive

Hey, its ok to have a jibe at me. Better fun if you do.

But, you did say this....remember.
Do NOT turn the wheel around!!!!

By doing this you flex the brush in the opposite direction and fatigue the wire causing them to break off - next thing you know you will be coated in the little wire bits.

I count 4 escalmation marks !.....Pretty heavy talk there Mark. Impleys this is how you do it. This is how you must do it. Your a complete bloody idiot if you do it any other way. Cause you'll end up in hosipital.

:confused: .....I've been through a few wheels, reversing them frequently, and I can be pretty ruff with them, and yet I haven't had any danger problems. And they've lasted a long time, seemingly longer than they did before I learn't of reversing wheels. (shrug) Should I stop doing it this way, even though it seems to be working ?

anyway, this topics getting a bit old seeya.

[Bodgy]

In my experience the wire wheels shed wires all the time, regardless. I always wear glasses and never, ever stand in line with the wheels rotation. I once had a cutting disc on a 9" angle grinder disintegrate on me. Pieces stuck in the ceiling walls etc., inches in.

I also walk on the wildside a bit. The grinder brass wire wheels cost $20-$30, the equivalent for a hand drill only $4 (priced at market). Drill out the centre of the latter and you can then mount on a 6' bench grinder. And, yes, the drill mount type is rated for the grinder RPM.