On 2013-12-17, dpb wrote:
On 12/17/2013 12:19 AM, DoN. Nichols wrote:

[ ... ]

Not saying anything about the mechanism, but it *does* happen.
Here is a report (from some not very specific time in the past):

================================================== ====================
http://www.handymanclub.com/connect/forums/aft/40499
================================================== ====================

I've got some new old (Co-op brand, even ) Al paint still around --
so I went and looked at one. There's nothing on the cans about not
shaking. I've not used a lot but did a little touchup with one a few
years ago. AFAICT they're still as good as new despite the age as far
as appearance in can and behavior in use goes. I didn't drive to town
to put one on the paint-store shaker but I did put it on the homebrew
vibrator I've cobbled together here out of an old combine pittman sickle
drive. It's not as fast and has a longer stroke compared to real shaker
but does get the stuff off the bottom...I don't remember noticing any
pressure after that when opening it (but then again I wasn't looking for
any as had never heard the stories/warnings).

Well ... the experience my friend had would have been in the
early 1960s, I think. (I never asked him, but he had a summer job in
the hardware store at the time, and I knew him first a few years later
at work.

And I've never seen a label on the paint warning about shaking
it, but I *have* seen such a warning label about aluminum paint on a
paint shaker bolted to a vertical floor-to-ceiling I-beam at work (a
later job) This was one of the kind which cranks two flat plates down on
each end of the can and shakes it around a horizontal axis through the
middle of the can half way between the two ends.

I don't know if there is more than one type of Al paint where there's a
significant difference in the makeup or not. I'd guess these go back to
around the late '70s/early '80s --

While his experience was (as mentioned above) likely in the
early 1960s.


[ ... ]

I'd like to see a real explanation--a quick search on manufacturers'
sites didn't bring anything to light.

I would too. But the one about the "tung oil" makes a certain
amount of sense.

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: | (KV4PH) Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"dpb" wrote in message ...
On 12/17/2013 12:19 AM, DoN. Nichols wrote:
On 2013-12-15, wrote:
On 12/15/2013 9:26 AM, Lloyd E. Sponenburgh wrote:
...

Neither have I had any paints heat from shaking, but it is possible
with
a natural vehicle paint, it's just not the aluminum causing the
problem;
it could happen with any linseed or tung oil paints. As you mentioned,
your rags are evidence of that.


I'd think it _highly_ unlikely the actual "accident" described actually
happened for the ascribed reason in the tale...

There's nothing that's _that_ chemically reactive there that simply
shaking even with the introduction of atmospheric air is going to
initiate that much of a chemical reaction to produce that amount of
pressure rise.

Not saying anything about the mechanism, but it *does* happen.
Here is a report (from some not very specific time in the past):

================================================== ====================
http://www.handymanclub.com/connect/forums/aft/40499
================================================== ====================

I've got some new old (Co-op brand, even ) Al paint still around --
so I went and looked at one. There's nothing on the cans about not
shaking. I've not used a lot but did a little touchup with one a few
years ago. AFAICT they're still as good as new despite the age as far as
appearance in can and behavior in use goes. I didn't drive to town to put
one on the paint-store shaker but I did put it on the homebrew vibrator
I've cobbled together here out of an old combine pittman sickle drive.
It's not as fast and has a longer stroke compared to real shaker but does
get the stuff off the bottom...I don't remember noticing any pressure
after that when opening it (but then again I wasn't looking for any as had
never heard the stories/warnings).

I don't know if there is more than one type of Al paint where there's a
significant difference in the makeup or not. I'd guess these go back to
around the late '70s/early '80s -- from the stuff in the old wellhouse it
looks like Dad bought out a bunch of the stock from the Co-op when it
closed the retail store in town but I'm not sure just when that was altho
it's been quite a long time ago now...I looked but didn't see anything on
the can that indicated a date -- even a tm or c on the label printing.
There's a manufacturer's mark which likely has a date in it but it's coded
to where can't decipher which letter/number(s) might be a year.

I'd like to see a real explanation--a quick search on manufacturers' sites
didn't bring anything to light.

--


Only precaution about shaking aluminum paint from
http://www.paintdocs.com/webmsds/web...rod no=B59S11

"Lightly stir before use. Do not shake with mechanical shaker or
overly agitate, as a dull, non-uniform, mottled appearance will
result."

On 18/12/13 04:53, DoN. Nichols wrote:
On 2013-12-17, dpb wrote:
On 12/17/2013 12:19 AM, DoN. Nichols wrote:
[ ... ]

Not saying anything about the mechanism, but it *does* happen.
Here is a report (from some not very specific time in the past):

================================================== ====================
http://www.handymanclub.com/connect/forums/aft/40499
================================================== ====================
I've got some new old (Co-op brand, even ) Al paint still around --
so I went and looked at one. There's nothing on the cans about not
shaking. I've not used a lot but did a little touchup with one a few
years ago. AFAICT they're still as good as new despite the age as far
as appearance in can and behavior in use goes. I didn't drive to town
to put one on the paint-store shaker but I did put it on the homebrew
vibrator I've cobbled together here out of an old combine pittman sickle
drive. It's not as fast and has a longer stroke compared to real shaker
but does get the stuff off the bottom...I don't remember noticing any
pressure after that when opening it (but then again I wasn't looking for
any as had never heard the stories/warnings).
Well ... the experience my friend had would have been in the
early 1960s, I think. (I never asked him, but he had a summer job in
the hardware store at the time, and I knew him first a few years later
at work.

And I've never seen a label on the paint warning about shaking
it, but I *have* seen such a warning label about aluminum paint on a
paint shaker bolted to a vertical floor-to-ceiling I-beam at work (a
later job) This was one of the kind which cranks two flat plates down on
each end of the can and shakes it around a horizontal axis through the
middle of the can half way between the two ends.

I've got a tin of cold galvanising paint that carries the following warning

"CAUTION
care should always be taken when removing the lids of tins containing
metallic paints as these are liable if contaminated (eg by moisture) to
a build up of pressure during storage.

DO NOT SHAKE

Open carefully, preferably shielded under rags, especially if the tin
has been allowed to stand part full. Apply with dry brush"

The tin is also the only one I have seen that came supplied with 2
spring clips to hold the lid in place.


I don't know if there is more than one type of Al paint where there's a
significant difference in the makeup or not. I'd guess these go back to
around the late '70s/early '80s --
While his experience was (as mentioned above) likely in the
early 1960s.


[ ... ]

I'd like to see a real explanation--a quick search on manufacturers'
sites didn't bring anything to light.
I would too. But the one about the "tung oil" makes a certain
amount of sense.

Enjoy,
DoN.

On 18 Dec 2013 04:53:45 GMT, "DoN. Nichols"
wrote:

On 2013-12-17, dpb wrote:

Well ... the experience my friend had would have been in the
early 1960s, I think. (I never asked him, but he had a summer job in
the hardware store at the time, and I knew him first a few years later
at work.

And I've never seen a label on the paint warning about shaking
it, but I *have* seen such a warning label about aluminum paint on a
paint shaker bolted to a vertical floor-to-ceiling I-beam at work (a
later job) This was one of the kind which cranks two flat plates down on
each end of the can and shakes it around a horizontal axis through the
middle of the can half way between the two ends.

Do you recall what it said? What type of warning was it? Mess or
explosion?


I don't know if there is more than one type of Al paint where there's a
significant difference in the makeup or not. I'd guess these go back to
around the late '70s/early '80s --

While his experience was (as mentioned above) likely in the
early 1960s.


[ ... ]

I'd like to see a real explanation--a quick search on manufacturers'
sites didn't bring anything to light.

I would too. But the one about the "tung oil" makes a certain
amount of sense.

I know people who have had smoldering fires from catalyzing oil finish
rags, so it's not just hearsay. I dry mine on the sidewalk for a week
before putting them in a trash can. Why take chances? When they're
hard, they're safe. Wet and crumpled, they get hot to the touch. My
first clue was picking up a hot rag in a cold shop. That brought the
warning home to me.

My two favorite wood finishes, Watco and Waterlox, are both catalyzing
oils and prone to that.

--
I merely took the energy it takes to pout and wrote some blues.
--Duke Ellington

On 12/17/2013 6:52 PM, Larry Jaques wrote:
Oh, hell. If you got it from the handyman club, it MUST be true.

Credibility comes in different flavors. If a handyman club post was
giving advice on some esoteric technical question, then skepticism would
be warranted. But when the post is about 1st person
this-happened-to-me, and the consequences weren't a matter of
interpretation ("...coated the floor, me, my boots, everything in
aluminum paint"), then I'm inclined to believe him. Why would he lie?

Bob

On 2013-12-18, Larry Jaques wrote:
On 18 Dec 2013 04:53:45 GMT, "DoN. Nichols"
wrote:

[ ... ]

And I've never seen a label on the paint warning about shaking
it, but I *have* seen such a warning label about aluminum paint on a
paint shaker bolted to a vertical floor-to-ceiling I-beam at work (a
later job) This was one of the kind which cranks two flat plates down on
each end of the can and shakes it around a horizontal axis through the
middle of the can half way between the two ends.

Do you recall what it said? What type of warning was it? Mess or
explosion?

Just "Do not use to shake aluminum paint!" (in big red letters,
IIRC. :-)

[ ... ]

I'd like to see a real explanation--a quick search on manufacturers'
sites didn't bring anything to light.

I would too. But the one about the "tung oil" makes a certain
amount of sense.

I know people who have had smoldering fires from catalyzing oil finish
rags, so it's not just hearsay. I dry mine on the sidewalk for a week
before putting them in a trash can. Why take chances? When they're
hard, they're safe. Wet and crumpled, they get hot to the touch. My
first clue was picking up a hot rag in a cold shop. That brought the
warning home to me.

I've always believed the warnings I learned in elementary school
science class, but I've not worked with those materials. I tend to also
put oily rags in a metal trash can, not a plastic one. :-)

My two favorite wood finishes, Watco and Waterlox, are both catalyzing
oils and prone to that.

O.K. So the remaining question is:f

"How hot can a half-full can of this get if shaken?"

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: | (KV4PH) Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On 20 Dec 2013 00:13:35 GMT, "DoN. Nichols"
wrote:

On 2013-12-18, Larry Jaques wrote:
On 18 Dec 2013 04:53:45 GMT, "DoN. Nichols"
wrote:

[ ... ]

And I've never seen a label on the paint warning about shaking
it, but I *have* seen such a warning label about aluminum paint on a
paint shaker bolted to a vertical floor-to-ceiling I-beam at work (a
later job) This was one of the kind which cranks two flat plates down on
each end of the can and shakes it around a horizontal axis through the
middle of the can half way between the two ends.

Do you recall what it said? What type of warning was it? Mess or
explosion?

Just "Do not use to shake aluminum paint!" (in big red letters,
IIRC. :-)

OK.


[ ... ]

I'd like to see a real explanation--a quick search on manufacturers'
sites didn't bring anything to light.

I would too. But the one about the "tung oil" makes a certain
amount of sense.

I know people who have had smoldering fires from catalyzing oil finish
rags, so it's not just hearsay. I dry mine on the sidewalk for a week
before putting them in a trash can. Why take chances? When they're
hard, they're safe. Wet and crumpled, they get hot to the touch. My
first clue was picking up a hot rag in a cold shop. That brought the
warning home to me.

I've always believed the warnings I learned in elementary school
science class, but I've not worked with those materials. I tend to also
put oily rags in a metal trash can, not a plastic one. :-)

Ditto.


My two favorite wood finishes, Watco and Waterlox, are both catalyzing
oils and prone to that.

O.K. So the remaining question is:f

"How hot can a half-full can of this get if shaken?"

No idea. As I said, I always 'argon it' if I don't have any Bloxygen
handy. (can of inert gas) http://tinyurl.com/mtryn95
Only $12.75 for a full twelve gram can.

--
I merely took the energy it takes to pout and wrote some blues.
--Duke Ellington

On 12/19/2013 6:13 PM, DoN. Nichols wrote:
On 2013-12-18, Larry wrote:
On 18 Dec 2013 04:53:45 GMT, "DoN.
wrote:

[ ... ]

And I've never seen a label on the paint warning about shaking
it, but I *have* seen such a warning label about aluminum paint on a
paint shaker bolted to a vertical floor-to-ceiling I-beam at work (a
later job) This was one of the kind which cranks two flat plates down on
each end of the can and shakes it around a horizontal axis through the
middle of the can half way between the two ends.

Do you recall what it said? What type of warning was it? Mess or
explosion?

Just "Do not use to shake aluminum paint!" (in big red letters,
IIRC. :-)

[ ... ]

I'd like to see a real explanation--a quick search on manufacturers'
sites didn't bring anything to light.

I would too. But the one about the "tung oil" makes a certain
amount of sense.

Totally different conditions and reaction than whatever's going on (if
anything) in the can.

I know people who have had smoldering fires from catalyzing oil finish
rags, so it's not just hearsay. I dry mine on the sidewalk for a week
before putting them in a trash can. Why take chances? When they're
hard, they're safe. Wet and crumpled, they get hot to the touch. My
first clue was picking up a hot rag in a cold shop. That brought the
warning home to me.

I've always believed the warnings I learned in elementary school
science class, but I've not worked with those materials. I tend to also
put oily rags in a metal trash can, not a plastic one. :-)

My two favorite wood finishes, Watco and Waterlox, are both catalyzing
oils and prone to that.

O.K. So the remaining question is:f

"How hot can a half-full can of this get if shaken?"
....

_IFF_ (the proverbial "big if") this is actually occurring (of which I'm
still not convinced there's not something else at play) I doubt it's
actually much temperature related (at least from internally generated
heat; the hypothesis of starting w/ something hot from exposure to sun
or the like aside)at all but some sort of outgassing or the like that's
generating the internal pressure rise with some modicum of additional
heat perhaps. If this were such a major issue it seems the cans would
have all sorts of warnings and it wouldn't need just a handwritten sign
on the mixer at the local co-op.

On the tales of spontaneous combustion, HS chemistry teacher used a rag
to wipe some spill from the lab counter after a demonstration in last
class period of day class and hung the rag on a clothes hook and closed
the door in a small closet. Next morning the door was heavily charred
in the area and the rag was mostly ash on the floor. Fortunately, it
appeared that lack of O2 in the small closet prevented full-fledged
fire. He purposely never let maintenance repair the door as a reminder
both to himself and students...was pretty effective teaching aid. I,
also, to this day, am certain to not leave finishing rags in precarious
places.

--

On 20/12/13 14:43, dpb wrote:
On 12/19/2013 6:13 PM, DoN. Nichols wrote:
On 2013-12-18, Larry wrote:
On 18 Dec 2013 04:53:45 GMT, "DoN.
wrote:

[ ... ]

And I've never seen a label on the paint warning about shaking
it, but I *have* seen such a warning label about aluminum paint on a
paint shaker bolted to a vertical floor-to-ceiling I-beam at work (a
later job) This was one of the kind which cranks two flat plates
down on
each end of the can and shakes it around a horizontal axis through the
middle of the can half way between the two ends.

Do you recall what it said? What type of warning was it? Mess or
explosion?

Just "Do not use to shake aluminum paint!" (in big red letters,
IIRC. :-)

[ ... ]

I'd like to see a real explanation--a quick search on manufacturers'
sites didn't bring anything to light.

I would too. But the one about the "tung oil" makes a certain
amount of sense.

Totally different conditions and reaction than whatever's going on (if
anything) in the can.

I know people who have had smoldering fires from catalyzing oil finish
rags, so it's not just hearsay. I dry mine on the sidewalk for a week
before putting them in a trash can. Why take chances? When they're
hard, they're safe. Wet and crumpled, they get hot to the touch. My
first clue was picking up a hot rag in a cold shop. That brought the
warning home to me.

I've always believed the warnings I learned in elementary school
science class, but I've not worked with those materials. I tend to also
put oily rags in a metal trash can, not a plastic one. :-)

My two favorite wood finishes, Watco and Waterlox, are both catalyzing
oils and prone to that.

O.K. So the remaining question is:f

"How hot can a half-full can of this get if shaken?"
...

_IFF_ (the proverbial "big if") this is actually occurring (of which
I'm still not convinced there's not something else at play) I doubt
it's actually much temperature related (at least from internally
generated heat; the hypothesis of starting w/ something hot from
exposure to sun or the like aside)at all but some sort of outgassing
or the like that's generating the internal pressure rise with some
modicum of additional heat perhaps. If this were such a major issue
it seems the cans would have all sorts of warnings and it wouldn't
need just a handwritten sign on the mixer at the local co-op.
I posted the warning message printed on the lid of some cold galvanising
paint I have, it would be difficult to miss when opening, on the 20th
and it said not to shake and also that pressure build can arise due to
moisture contamination. I wonder if the zinc reacts with the moisture to
produce some zinc compound and hydrogen resulting in a pressure build up
in the can.


On the tales of spontaneous combustion, HS chemistry teacher used a
rag to wipe some spill from the lab counter after a demonstration in
last class period of day class and hung the rag on a clothes hook and
closed the door in a small closet. Next morning the door was heavily
charred in the area and the rag was mostly ash on the floor.
Fortunately, it appeared that lack of O2 in the small closet prevented
full-fledged fire. He purposely never let maintenance repair the door
as a reminder both to himself and students...was pretty effective
teaching aid. I, also, to this day, am certain to not leave finishing
rags in precarious places.

--

On 12/20/2013 2:08 PM, David Billington wrote:
On 20/12/13 14:43, dpb wrote:
....

_IFF_ (the proverbial "big if") this is actually occurring (of which
I'm still not convinced there's not something else at play) I doubt
it's actually much temperature related (at least from internally
generated heat; the hypothesis of starting w/ something hot from
exposure to sun or the like aside)at all but some sort of outgassing
or the like that's generating the internal pressure rise with some
modicum of additional heat perhaps. If this were such a major issue it
seems the cans would have all sorts of warnings and it wouldn't need
just a handwritten sign on the mixer at the local co-op.

I posted the warning message printed on the lid of some cold galvanising
paint I have, it would be difficult to miss when opening, on the 20th
and it said not to shake and also that pressure build can arise due to
moisture contamination. I wonder if the zinc reacts with the moisture to
produce some zinc compound and hydrogen resulting in a pressure build up
in the can.
....

Perhaps but that's a completely different system than the Al paint of
the subthread discussion...

--

On 21/12/13 14:07, dpb wrote:
On 12/20/2013 2:08 PM, David Billington wrote:
On 20/12/13 14:43, dpb wrote:
...

_IFF_ (the proverbial "big if") this is actually occurring (of which
I'm still not convinced there's not something else at play) I doubt
it's actually much temperature related (at least from internally
generated heat; the hypothesis of starting w/ something hot from
exposure to sun or the like aside)at all but some sort of outgassing
or the like that's generating the internal pressure rise with some
modicum of additional heat perhaps. If this were such a major issue it
seems the cans would have all sorts of warnings and it wouldn't need
just a handwritten sign on the mixer at the local co-op.

I posted the warning message printed on the lid of some cold galvanising
paint I have, it would be difficult to miss when opening, on the 20th
and it said not to shake and also that pressure build can arise due to
moisture contamination. I wonder if the zinc reacts with the moisture to
produce some zinc compound and hydrogen resulting in a pressure build up
in the can.
...

Perhaps but that's a completely different system than the Al paint of
the subthread discussion...

--

I was thinking that reactions with aluminium are similar to zinc and
apparently aluminium can react with water to produce hydrogen gas.