Tip: blowing out fans

default wrote:
On Tue, 12 Nov 2019 14:55:44 -0800, T wrote:

On 11/12/19 5:55 AM, Jonathan N. Little wrote:
T wrote:
That would definitely be part of the design.

It is okay to spin the fan a little, just don't exceed
by much what it is designed to spin at. Some Air
Compressors can make that fan spin so faat, the
computer is about to take off!

And yes, it is fun. Resist the urge!

I finally found 60, 92 and 120 mm PWM fans I like.
A simple solution when blasting to remove stubborn crud on blades is a
finger on the fan BEFORE blasting away.

With canned air, that can get pretty cold! I put my
plastic ball point pen in them.

The stuff is cold because they use refrigerants. In fact there's
several DIY Utoobe vids of shade tree mechanics using "Dust Off"
products to recharge auto AC units because it can cost less. (and
they sell a side-piercing aerosol can tap for the purpose)

The danger to a computer might be from the cold - particularly if it
condesnses water from the air, causes thermal stress on connections,
or is powered up at temperatures it was not designed for.
And it is so, so much fun to see the blades whirl.
Damn that self control thing!

Well, there is that. Entertainment value.

The only part in a computer with a significant
exposure from "freeze mist", is a "DIP EPROM with window".
We killed a few of those, while doing thermal testing
on the bench. I don't remember other parts having
a problem with that sort of testing. The material
in the cans, was a freon-like product, and the
surface temperature achieved was around -55C or so.

If you thought a particular hardware interface had
marginal timing, you could use freeze mist to check.
It's human nature, to get carried away with that stuff.
It eventually disappeared from the market, that particular
product (Chemtronics, white spray can).

And windowed EPROMs were replaced with EEPROMs instead,
the electrically erasable ones. No more putting batches
of them in the UV eraser. I programmed quite a few
of those by hand in the lab.

And adiabatic expansion of gases, while generally
having a cooling effect...

https://lecdem.physics.umd.edu/i/i5/i5-15.html

that isn't always the case. I was going to use hydrogen
as an example, but hydrogen apparently has multiple
things working against it. Who knew... Keep these in
mind, when you see the new hydrogen-powered cars in the
showroom.

https://www.eng-tips.com/viewthread.cfm?qid=51712

Paul

On 2019-11-13 2:17 p.m., Paul wrote:
default wrote:
On Tue, 12 Nov 2019 14:55:44 -0800, T wrote:

On 11/12/19 5:55 AM, Jonathan N. Little wrote:
T wrote:
That would definitely be part of the design.

It is okay to spin the fan a little, just don't exceed
by much what it is designed to spin at.Â* Some Air
Compressors can make that fan spin so faat, the
computer is about to take off!

And yes, it is fun.Â* Resist the urge!

I finally found 60, 92 and 120 mm PWM fans I like.
A simple solution when blasting to remove stubborn crud on blades is a
finger on the fan BEFORE blasting away.

With canned air, that can get pretty cold!Â* I put my
plastic ball point pen in them.

The stuff is cold because they use refrigerants.Â* In fact there's
several DIY Utoobe vids of shade tree mechanics using "Dust Off"
products to recharge auto AC units because it can cost less.Â* (and
they sell a side-piercing aerosol can tap for the purpose)

The danger to a computer might be from the cold - particularly if it
condesnses water from the air, causes thermal stress on connections,
or is powered up at temperatures it was not designed for.
And it is so, so much fun to see the blades whirl.
Damn that self control thing!

Well, there is that.Â* Entertainment value.

The only part in a computer with a significant
exposure from "freeze mist", is a "DIP EPROM with window".
We killed a few of those, while doing thermal testing
on the bench. I don't remember other parts having
a problem with that sort of testing. The material
in the cans, was a freon-like product, and the
surface temperature achieved was around -55C or so.

If you thought a particular hardware interface had
marginal timing, you could use freeze mist to check.
It's human nature, to get carried away with that stuff.
It eventually disappeared from the market, that particular
product (Chemtronics, white spray can).

And windowed EPROMs were replaced with EEPROMs instead,
the electrically erasable ones. No more putting batches
of them in the UV eraser. I programmed quite a few
of those by hand in the lab.

And adiabatic expansion of gases, while generally
having a cooling effect...

https://lecdem.physics.umd.edu/i/i5/i5-15.html

that isn't always the case. I was going to use hydrogen
as an example, but hydrogen apparently has multiple
things working against it. Who knew... Keep these in
mind, when you see the new hydrogen-powered cars in the
showroom.

https://www.eng-tips.com/viewthread.cfm?qid=51712

Â*Â* Paul

On 2019-11-13 2:17 p.m., Paul wrote:
default wrote:
On Tue, 12 Nov 2019 14:55:44 -0800, T wrote:

On 11/12/19 5:55 AM, Jonathan N. Little wrote:
T wrote:
That would definitely be part of the design.

It is okay to spin the fan a little, just don't exceed
by much what it is designed to spin at. Some Air
Compressors can make that fan spin so faat, the
computer is about to take off!

And yes, it is fun. Resist the urge!

I finally found 60, 92 and 120 mm PWM fans I like.
A simple solution when blasting to remove stubborn crud on blades is a
finger on the fan BEFORE blasting away.

With canned air, that can get pretty cold! I put my
plastic ball point pen in them.

The stuff is cold because they use refrigerants. In fact there's
several DIY Utoobe vids of shade tree mechanics using "Dust Off"
products to recharge auto AC units because it can cost less. (and
they sell a side-piercing aerosol can tap for the purpose)

The danger to a computer might be from the cold - particularly if it
condesnses water from the air, causes thermal stress on connections,
or is powered up at temperatures it was not designed for.
And it is so, so much fun to see the blades whirl.
Damn that self control thing!

Well, there is that. Entertainment value.

The only part in a computer with a significant
exposure from "freeze mist", is a "DIP EPROM with window".
We killed a few of those, while doing thermal testing
on the bench. I don't remember other parts having
a problem with that sort of testing. The material
in the cans, was a freon-like product, and the
surface temperature achieved was around -55C or so.

If you thought a particular hardware interface had
marginal timing, you could use freeze mist to check.
It's human nature, to get carried away with that stuff.
It eventually disappeared from the market, that particular
product (Chemtronics, white spray can).

And windowed EPROMs were replaced with EEPROMs instead,
the electrically erasable ones. No more putting batches
of them in the UV eraser. I programmed quite a few
of those by hand in the lab.

And adiabatic expansion of gases, while generally
having a cooling effect...

https://lecdem.physics.umd.edu/i/i5/i5-15.html

that isn't always the case. I was going to use hydrogen
as an example, but hydrogen apparently has multiple
things working against it. Who knew... Keep these in
mind, when you see the new hydrogen-powered cars in the
showroom.

https://www.eng-tips.com/viewthread.cfm?qid=51712

Paul

I used a lot of Freeze-T to test for thermal resistors in TV sets which
caused vertical roll and horizontal tearing in TV sets.

Never used it on eproms, But way back then I built an eprom burner to
burn monitor roms and small programs for the Apple II and Apple GS
computers on 2716 and 2732 roms, For the 25 volt DC required I used
three 9 volt batteries in series. For erasing I had an enclosed U shaped
UV lamp in an aluminum enclosure with a sliding lid.

Rene

On Wed, 13 Nov 2019 15:17:23 -0500, Paul
wrote:

default wrote:
On Tue, 12 Nov 2019 14:55:44 -0800, T wrote:

On 11/12/19 5:55 AM, Jonathan N. Little wrote:
T wrote:
That would definitely be part of the design.

It is okay to spin the fan a little, just don't exceed
by much what it is designed to spin at. Some Air
Compressors can make that fan spin so faat, the
computer is about to take off!

And yes, it is fun. Resist the urge!

I finally found 60, 92 and 120 mm PWM fans I like.
A simple solution when blasting to remove stubborn crud on blades is a
finger on the fan BEFORE blasting away.

With canned air, that can get pretty cold! I put my
plastic ball point pen in them.

The stuff is cold because they use refrigerants. In fact there's
several DIY Utoobe vids of shade tree mechanics using "Dust Off"
products to recharge auto AC units because it can cost less. (and
they sell a side-piercing aerosol can tap for the purpose)

The danger to a computer might be from the cold - particularly if it
condesnses water from the air, causes thermal stress on connections,
or is powered up at temperatures it was not designed for.
And it is so, so much fun to see the blades whirl.
Damn that self control thing!

Well, there is that. Entertainment value.

The only part in a computer with a significant
exposure from "freeze mist", is a "DIP EPROM with window".
We killed a few of those, while doing thermal testing
on the bench. I don't remember other parts having
a problem with that sort of testing. The material
in the cans, was a freon-like product, and the
surface temperature achieved was around -55C or so.

If you thought a particular hardware interface had
marginal timing, you could use freeze mist to check.
It's human nature, to get carried away with that stuff.
It eventually disappeared from the market, that particular
product (Chemtronics, white spray can).

And windowed EPROMs were replaced with EEPROMs instead,
the electrically erasable ones. No more putting batches
of them in the UV eraser. I programmed quite a few
of those by hand in the lab.

And adiabatic expansion of gases, while generally
having a cooling effect...

https://lecdem.physics.umd.edu/i/i5/i5-15.html

that isn't always the case. I was going to use hydrogen
as an example, but hydrogen apparently has multiple
things working against it. Who knew... Keep these in
mind, when you see the new hydrogen-powered cars in the
showroom.

https://www.eng-tips.com/viewthread.cfm?qid=51712

Paul

I always hold the can under a hot-water tap. Works for spray paint
too.

You get a real blast!

On 11/14/19 6:21 PM, Peter Jason wrote:
On Wed, 13 Nov 2019 15:17:23 -0500, Paul
wrote:

default wrote:
On Tue, 12 Nov 2019 14:55:44 -0800, T wrote:

On 11/12/19 5:55 AM, Jonathan N. Little wrote:
T wrote:
That would definitely be part of the design.

It is okay to spin the fan a little, just don't exceed
by much what it is designed to spin at. Some Air
Compressors can make that fan spin so faat, the
computer is about to take off!

And yes, it is fun. Resist the urge!

I finally found 60, 92 and 120 mm PWM fans I like.
A simple solution when blasting to remove stubborn crud on blades is a
finger on the fan BEFORE blasting away.

With canned air, that can get pretty cold! I put my
plastic ball point pen in them.

The stuff is cold because they use refrigerants. In fact there's
several DIY Utoobe vids of shade tree mechanics using "Dust Off"
products to recharge auto AC units because it can cost less. (and
they sell a side-piercing aerosol can tap for the purpose)

The danger to a computer might be from the cold - particularly if it
condesnses water from the air, causes thermal stress on connections,
or is powered up at temperatures it was not designed for.
And it is so, so much fun to see the blades whirl.
Damn that self control thing!

Well, there is that. Entertainment value.

The only part in a computer with a significant
exposure from "freeze mist", is a "DIP EPROM with window".
We killed a few of those, while doing thermal testing
on the bench. I don't remember other parts having
a problem with that sort of testing. The material
in the cans, was a freon-like product, and the
surface temperature achieved was around -55C or so.

If you thought a particular hardware interface had
marginal timing, you could use freeze mist to check.
It's human nature, to get carried away with that stuff.
It eventually disappeared from the market, that particular
product (Chemtronics, white spray can).

And windowed EPROMs were replaced with EEPROMs instead,
the electrically erasable ones. No more putting batches
of them in the UV eraser. I programmed quite a few
of those by hand in the lab.

And adiabatic expansion of gases, while generally
having a cooling effect...

https://lecdem.physics.umd.edu/i/i5/i5-15.html

that isn't always the case. I was going to use hydrogen
as an example, but hydrogen apparently has multiple
things working against it. Who knew... Keep these in
mind, when you see the new hydrogen-powered cars in the
showroom.

https://www.eng-tips.com/viewthread.cfm?qid=51712

Paul

I always hold the can under a hot-water tap. Works for spray paint
too.

You get a real blast!

For the spray paint cans, I used to just "soak" them in a pan of hot
water, shaking the can occasionally, until the contents were warmed all
the way though. Really gave me a great looking result.


--
Ken
MacOS 10.14.6
Firefox 69.0.2
Thunderbird 60.9
"My brain is like lightning, a quick flash
and it's gone!"