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Shedhand
15th March 2006, 10:36 PM
Just had a damn close shave with a wire wheel. Put a new wire wheel in my bench grinder. Grabbed a rusty chip breaker out of an old Carter I picked up put it to the wheel....whack. :eek: Grabbed the bloody thing out of my hand and flung it across the shed at hgh speed and put a hole in the fibro. :eek: Missed my already busted right wing by a mere few bees d*cks. :eek:

A valuable lesson learnt. Never used one before.:o Gonna be VERY careful.

Wood Butcher
15th March 2006, 10:45 PM
I remember at my old TAFE they had a big (real big) pedestal grinder with a wire wheel on one side. One night a bloke was cleaning up a bolt when the wheel grabbed it, sucked it into the wheel cover then spat it out the top of the guard straight towards his head. Fortunately we had a safety nazi of a teacher and wearing a full face sheild was compulsary when using grinders.

Glad to hear your ok shedhand!

Shedhand
15th March 2006, 10:48 PM
I remember at my old TAFE they had a big (real big) pedestal grinder with a wire wheel on one side. One night a bloke was cleaning up a bolt when the wheel grabbed it, sucked it into the wheel cover then spat it out the top of the guard straight towards his head. Fortunately we had a safety nazi of a teacher and wearing a full face sheild was compulsary when using grinders.

Glad to hear your ok shedhand!Frightened the tripe out of me...I had a nazi woody teacher like that. I obviously forgot the lesson.:o

Waldo
15th March 2006, 11:13 PM
G'day Shedland,

Now if it happened in your new shed, then the impression of a chip breaker embedded in one of the walls would've made an interesting conversation starter.

Shedhand
16th March 2006, 12:40 AM
G'day Shedland,

Now if it happened in your new shed, then the impression of a chip breaker embedded in one of the walls would've made an interesting conversation starter.I gotta spare sheet of colourbond wall cladding. Would have replaced the imprinted one immediately. Be too embarrased to let anyone ask the obvious question.:o;) Rather the wall though than my head.;)

JDarvall
16th March 2006, 04:27 AM
:D done that.

Gota drag the item your brushing. Like buffing wheels. Or else it crash dives. Need a firm grip as well as you've found out. Whats hard is trying ot brush a small piece that you can't grab very well cause of its size. As soon as it goes flying in my shed its guarenteed lost, due to all the crap on the floor.

And you gota resist the temptation to press into them too hard. That wears them quite fast. Occationally good to reverse the direction of the grinder as well. Which will probably mean you'll have to unbolt it and flip it

Think overall their pretty safe. As long as you where safety glasses. The wire breaks off as well,,,,can fly into your eye. I don't think I'd bother going as far as a full face sheild though. :D Spose you gota be a nazi nodays, with all this insurance stuff in high gear.

MurrayD99
16th March 2006, 07:27 AM
The company I am working for does video motion detection sensors. I guess you didn't need one for this violent little UFO - but if you ever seriously want to trap one on film, we have a very rigorously tested product.... not that we caught one ourselves yet. Still testing.

Simomatra
18th March 2006, 12:56 PM
The Nazi teachers and instructors say today that all moving machinery ie grinders fixed and portable drills buffers etc require double protection

ie safety glasses and full face shield

Rember you only get one set of eyes

Cheers Sam

Shedhand
18th March 2006, 01:57 PM
The Nazi teachers and instructors say today that all moving machinery ie grinders fixed and portable drills buffers etc require double protection

ie safety glasses and full face shield

Rember you only get one set of eyes

Cheers SamEyes are stuffed anyway (diabetes). I wear multi-focals. If I put goggles or a full face shield on I just can't focus properly. I try and work slightly to the side of the wheels to lessen the chance of being hit in the face. That's why my arms generally cop it with bits of wire and steel. Getting used to the pain. :o Hmmm...;)
When I finally cark it I'm gonna come back with perfect vision and an immunity to bloddy arthritis. Don't care about the rest.:cool:

DanP
18th March 2006, 02:16 PM
I don't think I'd bother going as far as a full face sheild though.

Wait till you get one of those wires embedded in your cheek. DAMHIK:eek:

It doesn't hurt too much going in, in fact you barely notice it. Getting it out is another story...:eek: :eek: :eek:

Dan

journeyman Mick
18th March 2006, 10:55 PM
You definitely want to wear a face shield. I've never got a bit of wire buff stuck in my cheek but I did get one in my leg- it went clean through my jeans and I didn't feel it until I took my pants off that afternoon OUCH!:mad: I had to reef it out with pliers as it was turned over on the end like a hook. If that happened to your face itcould be very nasty.

Mick

boban
18th March 2006, 11:25 PM
Ive always been paranoid about my hearing but it took me two trips to the hospital and a couple to the opthamologist to realise just how vulnerable your eyes are.

Both of those incidents involved me wearing the wrong type of eye protection. Unlucky I guess, but you soon realise that it could have been a lot worse.

RufflyRustic
18th March 2006, 11:32 PM
This afternoon I hung one pot plant up, then went and did something else and in the process, took my safety glasses off. Came back 10 minutes later, yes, without the glasses to hang the last two potplants. Holy YeOw!! what's that in my eyes!!!!!!!!!!!!!!!!!!!!!!!!!:mad: :eek: :confused: Good thing I know the back patio area well as I was running blind to the bathroom to flush my eyes out. :rolleyes:

Sigh!!

Wendy

DanP
19th March 2006, 12:53 AM
it was turned over on the end like a hook.

Mine was reasonably straight but still hurt like hell coming out.:eek: :eek:

Dan

soundman
19th March 2006, 10:52 PM
A wire wheel on a bench grinder is a wonderfull thing but there are some traps.

On my opinion the standard wheel housing is totaly unsuitable for use with a wire wheel and never use a tool rest particularly with small items.
Choosing a relativly soft wheel is a good move.
Always present the job to the wheel from below ( top of the wheel turning toward you), that way WHEN the job catches it will be thrown to the ground and the majority of the waste ( and nasty wires ) will be thrown down and away from you.
And yess a firm hold on the job is the go.
This is one tool that you do not want any loose clothing.
I recon the best guard for one of these would be a flat piece of acrilic over the top of the machine hinged from the back with plenty of room between the machine and the shield.
Never wear gloves. Get your fingers in the wheel you might loose a bit of skin with gloves on you risk loosing fingers. Pliers feel no pain.

cheers

Markw
20th March 2006, 01:25 PM
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
20th March 2006, 01:27 PM
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 wayOK. Thanks. I won't turn the wheel around. I did wonder about the wisdom of doing so.:o
Cheers

JDarvall
20th March 2006, 05:56 PM
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
20th March 2006, 06:22 PM
: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
20th March 2006, 07:43 PM
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 !....:D

JDarvall
20th March 2006, 08:01 PM
Sorry, I put the wrong photo in......I should have put this photo instead of 2nd picture above.

Shedhand
20th March 2006, 08:31 PM
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
20th March 2006, 10:02 PM
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
20th March 2006, 10:31 PM
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 !....:D

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
20th March 2006, 10:42 PM
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
20th March 2006, 11:00 PM
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
20th March 2006, 11:20 PM
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
20th March 2006, 11:23 PM
G'day Shedland,

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

JDarvall
21st March 2006, 06:25 AM
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 :) :)

:D 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 :D seeya.

Bodgy
21st March 2006, 09:18 AM
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.

soundman
24th March 2006, 01:13 PM
I can see both sides of the reversing argument.

The result would be variable with the type and quality of wheel.

I have in the past turned a wheel arround and yess it proceeded to shed like a golden retriever comming into summer. it was a cheep soft straight laid wheel.

however if we we're talking about a heavy twist knot wheel I can see that it would wear unevenly & reversing it probably wont bother it because the base of the wires wont flex a hell of a lot.

The type of use may also cause differing results.
If the wheel was mounted on a bench grinder and always used with a light touch AND the wheel was good quality it probaly would not make a blind bit of difference either way.
If however the wheel was mounted in a hand held power tool and used in a heavy application (such as descaling plate steel) and the wheel was of cheaper manufacture things may be completely different.


It occurs to me that there is good reason for the generaly accepted workshop dogma, BUT I also occurs to me that modern qulaity manufacturing may overcome previous valid concerns in many matters.


Personaly I wouldn't reverse a soft straight laid wheel on my bench grinder.
If its getting that bad I would probaby replace it. They are cheap enough these days.

BTW any experienced wire wheel user will tell you the most wires are often shed in the first few hours of use.


cheers

Shedhand
24th March 2006, 01:35 PM
I forgot to say that it's a twisted wire wheel.

soundman
29th March 2006, 10:42 PM
:eek: yikes Twist knot wheels are prety damn agressive.
I don't think I'd be game to work hand held to a bench grinder with one on it.
For a wire wheel to use kleening stuff up in the workshop particularly if you are dealing with relativly small parts I'd be going for a soft straight laid wheel.

Twits knot wheel...... man I want to have all my body parts a safe distance from that.

Now I'm not saying that I'd clean the dirt from under my fingernails with a soft wire wheel but, minor accidental contact with the wheel is not a major crisis.

A twist knot wheel on the other hand will rip big chunks out of you.


Keep some body filler handy:D

cheers

Shedhand
29th March 2006, 11:52 PM
Sound advice Soundman (no pun intended). :cool: Its a pity the guy who sold it to me didn't warn me. I bought the twisted one because I thought it would last longer and throw less wire out as it wore down. Guess I'll by a soft untwisted one and keep this one for tough stuff.
Thanks:o