Someone near me is advertising a 14" pedestal grinder. It is similar
in construction (but not brand) to this grinder.

http://tinyurl.com/y8k9mjl

In other words, it is huge, 5 to 7.5 HP depending on wheel width.

While the size of this grinder fascinates me, I cannot help but wonder
how can people even get the full power out of it.

Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks

Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks

Ignoramus

This is a big grinder as things so. But I can't figure out how the
wheel size relates to the power. Or possibly how wheel size changes
power. Of course size cvan be a factor in safety but a friend in a
blacksmith shop has three grinders ove 10 HP and has no problems. He
knows how to handle things like this.

Do you have the proper power for this? Probably 3 phase 220 or more.

Bob AZ

On 2009-11-02, Bob AZ wrote:
This is a big grinder as things so. But I can't figure out how the
wheel size relates to the power.

Maybe a wider wheel can remove more material per minute.

Or possibly how wheel size changes power. Of course size cvan be a
factor in safety but a friend in a blacksmith shop has three
grinders ove 10 HP and has no problems. He knows how to handle
things like this.

OK, so, how do they use these grinders? Why do they need to much
power? Maybe I can learn something.

Do you have the proper power for this? Probably 3 phase 220 or more.

Not a problem AT ALL.

i

On Sun, 01 Nov 2009 19:38:35 -0600, Ignoramus17693
wrote:

Someone near me is advertising a 14" pedestal grinder. It is similar
in construction (but not brand) to this grinder.

http://tinyurl.com/y8k9mjl

In other words, it is huge, 5 to 7.5 HP depending on wheel width.

While the size of this grinder fascinates me, I cannot help but wonder
how can people even get the full power out of it.

Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks


If you buy it..I have brand new wheels Ill give you simply for the
shipping

Gunner

"IMHO, some people here give Jeff far more attention than he deserves,
but obviously craves. The most appropriate response, and perhaps the
cruelest, IMO, is to simply killfile and ignore him. An alternative, if
you must, would be to post the same standard reply to his every post,
listing the manifold reasons why he ought to be ignored. Just my $0.02
worth."

Ignoramus17693 wrote:
Someone near me is advertising a 14" pedestal grinder. It is similar
in construction (but not brand) to this grinder.

http://tinyurl.com/y8k9mjl

In other words, it is huge, 5 to 7.5 HP depending on wheel width.

While the size of this grinder fascinates me, I cannot help but wonder
how can people even get the full power out of it.

Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks



I've never seen a bench mounted grinder that size , but have used a few
that have been made as floor mounted models .
The 14" wheels rotate slower that say an 8 ' bench model .
They are used for rough fettling of castings and large pieces of steel
etc, they will take a fair bit of pressure and will remove large amounts
of material quickly..


--
Kevin (Bluey)
"I'm not young enough to know everything."

Ignoramus17693 wrote:
Someone near me is advertising a 14" pedestal grinder. It is similar
in construction (but not brand) to this grinder.

http://tinyurl.com/y8k9mjl

In other words, it is huge, 5 to 7.5 HP depending on wheel width.

While the size of this grinder fascinates me, I cannot help but wonder
how can people even get the full power out of it.

Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks

I've never seen a bench mounted grinder that size , but have used a few
that have been made as floor mounted models .
The 14" wheels rotate slower that say an 8" bench model .
They are used for rough fettling of castings and large pieces of steel
etc, they will take a fair bit of pressure and will remove large amounts
of material quickly..

They are no more dangerous than any other grinder of the type
,ceratainly less dangerous that a hand held angle grinder.
If I had 3 phase power in my workshop I would certainly have one.

--
Kevin (Bluey)
"I'm not young enough to know everything."

In article ,
Ignoramus17693 wrote:

Someone near me is advertising a 14" pedestal grinder. It is similar
....
Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

As far as the size-related hazards, don't take the guards off. Even
small stones can kill when they fail - big ones are better at it. And
watch that loose clothing - you might stall a 1 hp grinder and get your
hand dragged into a 5hp unit from the same sleeve snag.

You can obviously spin any size stone up with as small a motor as you
like, if you don't manage to fry the motor while bringing the stone up
to speed from inertia - but the point of a grinder is to remove
material, and being able to shove material into the stone and have it
ground away is what they are for - not needing a long-ramp VFD to start
the thing is a side benefit of using a "large enough" motor. That said,
plenty of home shops would likely be fine with 1-1.5 hp driving (but
that's hard to do on a grinder of that design, rather than one with a
belt drive where swapping the motor is easy) since one rarely reefs on
the equipment as hard as in a production shop. You'd still get the
benefit of a larger radius on the grind, and the downside of how much
the stones cost, but the upside of how far you can grind them down
without being too small.

Of course, less inertia, less hazard from failure and less media cost
(for home-type use) with large (or no) radius can be had with a belt
sander, where you can use the contact wheel the same as a grinder, or
the flat platen. Cue horrified gasps, since there are slight differences
between grinding on a belt sander and grinding on a stone, but with a
properly tensioned belt sander they are pretty minor. I'll let someone
else dissect them at length.

--
Cats, coffee, chocolate...vices to live by

On 2009-11-02, Gunner Asch wrote:
On Sun, 01 Nov 2009 19:38:35 -0600, Ignoramus17693
wrote:

Someone near me is advertising a 14" pedestal grinder. It is similar
in construction (but not brand) to this grinder.

http://tinyurl.com/y8k9mjl

In other words, it is huge, 5 to 7.5 HP depending on wheel width.

While the size of this grinder fascinates me, I cannot help but wonder
how can people even get the full power out of it.

Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks


If you buy it..I have brand new wheels Ill give you simply for the
shipping

This is awesome. If I win it, I will take you up on your offer. I can
prepay a label, it will be cheaper for me.

Thanks Gunner.

So... Have you seen people use those beasts? How are they used?

I

On Nov 1, 8:56*pm, Bob AZ wrote:
Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks

Ignoramus

This is a big grinder as things so. But I can't figure out how the
wheel size relates to the power. Or possibly how wheel size changes
power. Of course size cvan be a factor in safety but a friend in a
blacksmith shop has three grinders ove 10 HP and has no problems. He
knows how to handle things like this.

Do you have the proper power for this? Probably 3 phase 220 or more.

Bob *AZ

Power is directly related to the moment of inertia, the bigger that is
for the object being spun, the more power required. Generally, you're
going on the basis of surface feet per minute, so you don't have to
spin a large wheel as fast as a small one to get the same sfm. Power
required goes up as the square of the rpm, if the wheel moment of
inertia stays the same. Just some of the variables to play with.

Stan

On Mon, 02 Nov 2009 07:39:33 -0600, Ignoramus13931
wrote:

On 2009-11-02, Gunner Asch wrote:
On Sun, 01 Nov 2009 19:38:35 -0600, Ignoramus17693
wrote:

Someone near me is advertising a 14" pedestal grinder. It is similar
in construction (but not brand) to this grinder.

http://tinyurl.com/y8k9mjl

In other words, it is huge, 5 to 7.5 HP depending on wheel width.

While the size of this grinder fascinates me, I cannot help but wonder
how can people even get the full power out of it.

Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks


If you buy it..I have brand new wheels Ill give you simply for the
shipping

This is awesome. If I win it, I will take you up on your offer. I can
prepay a label, it will be cheaper for me.

Thanks Gunner.

So... Have you seen people use those beasts? How are they used?

I

Besides "carefully"?

You simply use them like any other grinder. They dont spin all that
fast ..but because of the size of the wheel..it keeps up the SFM.

Shrug...they work good, and its really really really hard to stall one.

As someone said..dont get your sleeve snagged in one. Other than
that..use em like you would a regular grinder.

Gunner


"IMHO, some people here give Jeff far more attention than he deserves,
but obviously craves. The most appropriate response, and perhaps the
cruelest, IMO, is to simply killfile and ignore him. An alternative, if
you must, would be to post the same standard reply to his every post,
listing the manifold reasons why he ought to be ignored. Just my $0.02
worth."

On Mon, 2 Nov 2009 09:29:46 -0800 (PST), wrote:

On Nov 1, 8:56*pm, Bob AZ wrote:
Also do you think that they are much more dangerous than regular
1/2-1HP grinders.

thanks

Ignoramus

This is a big grinder as things so. But I can't figure out how the
wheel size relates to the power. Or possibly how wheel size changes
power. Of course size cvan be a factor in safety but a friend in a
blacksmith shop has three grinders ove 10 HP and has no problems. He
knows how to handle things like this.

Do you have the proper power for this? Probably 3 phase 220 or more.

Bob *AZ

Power is directly related to the moment of inertia, the bigger that is
for the object being spun, the more power required. Generally, you're
going on the basis of surface feet per minute, so you don't have to
spin a large wheel as fast as a small one to get the same sfm. Power
required goes up as the square of the rpm, if the wheel moment of
inertia stays the same. Just some of the variables to play with.

Stan

The moment of inertia only affects how long it takes the wheel to get
up to speed. That energy comes from the motor and is stored in the
wheel(s) (it is lost to friction etc. when you turn the motor off).

Steady-state power is related to the drag on the surface of the wheel
* sfm (work = force * distance, and power is work per unit time).