Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor shaft
or check to make sure your fan is not secured by only one bolt before
buying it.

On Mon, 03 Jan 2011 20:47:48 -0800, Molly Brown wrote:

Any centrifugal fan that is secured to the fan motor shaft with only one
bolt will eventually become loose and begin to hit the fan cage.

Surely any fan with just one bolt will have the threads cut in the
opposite direction to the motor's rotation, so that the motor's turning
will have a tendency to tighten the bolt rather than loosen it? Or have
you seen designs where this isn't the case?

cheers

Jules

On Jan 3, 8:56*pm, Jules Richardson
wrote:
On Mon, 03 Jan 2011 20:47:48 -0800, Molly Brown wrote:
Any centrifugal fan that is secured to the fan motor shaft with only one
bolt will eventually become loose and begin to hit the fan cage.

Surely any fan with just one bolt will have the threads cut in the
opposite direction to the motor's rotation, so that the motor's turning
will have a tendency to tighten the bolt rather than loosen it? Or have
you seen designs where this isn't the case?

cheers

Jules

http://www.masterplumber.net/images/HPIM1470.JPG

Molly Brown wrote:
Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor shaft
or check to make sure your fan is not secured by only one bolt before
buying it.
Gmm,
Never happened to me. Use some locktite for the bolt thread.

On Jan 3, 11:47*pm, Molly Brown wrote:
Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor shaft
or check to make sure your fan is not secured by only one bolt before
buying it.

Millions of them around that have not failed seems to contradict your
theory.

On Jan 4, 6:56*am, jamesgangnc wrote:
On Jan 3, 11:47*pm, Molly Brown wrote:

Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor shaft
or check to make sure your fan is not secured by only one bolt before
buying it.

Millions of them around that have not failed seems to contradict your
theory.

Many commercial designs have 2 set-screws...one on top of the other.
(same tapped hole)

That looks just like the one I cleaned last week. Outdoors,
with a garden hose makes for cold hands on a winter day.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Molly Brown" wrote in message
...

http://www.masterplumber.net/images/HPIM1470.JPG

The fans I've seen, the bolt comes in from the side, and
presses on the flat side of the shaft.

Yes, sometimes they do loosen up. Happens with pulleys,
also. The bolts loosen up and the pulley falls off. I saw
that a couple weeks ago, one of the furnace at my church had
the pulley fall off.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Jules Richardson" wrote
in message ...
On Mon, 03 Jan 2011 20:47:48 -0800, Molly Brown wrote:

Any centrifugal fan that is secured to the fan motor shaft
with only one
bolt will eventually become loose and begin to hit the fan
cage.

Surely any fan with just one bolt will have the threads cut
in the
opposite direction to the motor's rotation, so that the
motor's turning
will have a tendency to tighten the bolt rather than loosen
it? Or have
you seen designs where this isn't the case?

cheers

Jules

Can also put on a couple drops of Loctite. Both where the
shaft meets the fan, and also to tighten the threads of the
hold down bolt.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Molly Brown" wrote in message
...
Any centrifugal fan that is secured to the fan motor shaft
with only
one bolt will eventually become loose and begin to hit the
fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out.
These types
of fans are usually found in furnaces. It may be possible to
avoid
this by drilling and tapping a second hole perpendicular to
the first
one on the fan for another bolt to better secure it to the
motor shaft
or check to make sure your fan is not secured by only one
bolt before
buying it.

On Tue, 04 Jan 2011 09:24:57 -0500, Stormin Mormon wrote:

Can also put on a couple drops of Loctite. Both where the shaft meets
the fan, and also to tighten the threads of the hold down bolt.

Yep, I'd expect some kind of thread sealer in conjunction with properly
torquing down the bolt would do the job - unless the fan was allowed to
get so choked with crap over time that vibration became significant (but
that's what periodic maintenance is for, right? :-)

(re. your other comment about a hose - you're lucky, my outside faucets
are about 3' beneath the snow and will be for another few months :-)

cheers

Jules

On 1/3/2011 10:47 PM, Molly Brown wrote:
Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor shaft
or check to make sure your fan is not secured by only one bolt before
buying it.

I've never heard of one coming loose ever. It's usually the opposite,
you can't remove the dam things with a jackhammer.

--
Steve Barker
remove the "not" from my address to email

On Jan 4, 11:09*am, Steve Barker wrote:
On 1/3/2011 10:47 PM, Molly Brown wrote:

Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor shaft
or check to make sure your fan is not secured by only one bolt before
buying it.

I've never heard of one coming loose ever. *It's usually the opposite,
you can't remove the dam things with a jackhammer.

--
Steve Barker
remove the "not" from my address to email

Ain't that the truth :-)

Steve Barker wrote:
On 1/3/2011 10:47 PM, Molly Brown wrote:
Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor
shaft or check to make sure your fan is not secured by only one bolt
before buying it.

I've never heard of one coming loose ever. It's usually the opposite,
you can't remove the dam things with a jackhammer.

I recently took the squirrel cage from a centrifugal blower off of the motor
shaft (it was from an ancient oil burning furnace). It was attached with
*one* set screw, and came off without too much trouble, despite having set
out in the rain for a number of years. There was no evidence on the shaft
of having ever slipped over the years (mind you, this was a 1/8HP motor,
albeit a fairly large 1/8HP motor).

Jon

On Jan 3, 10:47*pm, Molly Brown wrote:
Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor shaft
or check to make sure your fan is not secured by only one bolt before
buying it.

It depends on whether the securing bolt/machine screw comes in from
the side or whether the fan is held on by a nut on the end of the
motor shaft itself. You don't say which you mean so the premise is
faulty, as in FAWLTY TOWERS.

On Jan 4, 4:47*am, Molly Brown wrote:
Any centrifugal fan that is secured to the fan motor shaft with only
one bolt will eventually become loose and begin to hit the fan cage.
This is especially so for fans that are heavy and operated
horizontally. A fan that is hitting its cage will cause the
temperature cut-out to trip and will eventually burn-out. These types
of fans are usually found in furnaces. It may be possible to avoid
this by drilling and tapping a second hole perpendicular to the first
one on the fan for another bolt to better secure it to the motor shaft
or check to make sure your fan is not secured by only one bolt before
buying it.

It my experience they are more likely to corrode solid on to the shaft
& be difficult to remove without applying heat &WD40 If it's catching
on the fan housing, the noise will make this very apparent.

Would that be "Snow Ho-s?" Or, maybe "Ho In De Sno"? I
didn't feel lucky as I warmed my fingers over the gas burner
on her kitchen stove.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Jules Richardson"
wrote in message
...

(re. your other comment about a hose - you're lucky, my
outside faucets
are about 3' beneath the snow and will be for another few
months :-)

cheers

Jules

Snowblowers have that problem. Lots and lots of heat
sometimes helps.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Steve Barker" wrote in message
...

one on the fan for another bolt to better secure it to the
motor shaft
or check to make sure your fan is not secured by only one
bolt before
buying it.

I've never heard of one coming loose ever. It's usually the
opposite,
you can't remove the dam things with a jackhammer.

--
Steve Barker
remove the "not" from my address to email