*Putting* water in your DC collection bin?

Page 2 of 3  
It's not me you should agree with, it's reality.
Find another source of ignition anywhere but in your imagination? Please let us know.
The water of precise knowledge is in front of you. Drink.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Oily rags are not fresh manure or wet hay, and yet they can spontaneously combust.

Oh, the irony.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
By the same mechanism, if you had the sense to search!
wrote:

Please
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
George wrote:

I would much rather it be in my imagination than in my dust collector.

ROF,L.
--
--John
Reply to jclarke at ae tee tee global dot net
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

So your statement, without weasel-words built in as you have done, is "Sawdust from a woodworking shop cannot spontaneously combust", yes or no?

And yet, there are people who don't understand it, and will expand one situation to an unlrelated situation.

That's kind of amusing to read, since I'm the one in the back of the ambulance, working on the patient.
Draw a venn diagram of your sawdust/manure/fire theory, and you can show yourself where the flaw in your logic is.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Yeah, me too. So how is it you have such contempt for precise knowledge?
Not theory, but fact. Once again, that's what science is - reproducible, and everywhere the same.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yeah, me too, WHAT? WTF are you responding to, George? You don't even see with this blatant example, why your insistance on top-posting inhibits communication? I have no contempt for precise knowledge. Why don't you try exhibiting some and we'll see if you can.


I notice you ignored this. Do you have _any_ point to make here, George, or are you just making noise to listen to yourself?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Venn diagrams are meaningless in cause-effect relationships. "Communication" with the unreasoning is impossible.
I would expect someone else with a medic's card to have some scientific background, and respect for learning. In your case, I'm wrong.
wrote:

knowledge?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Good lord. You must be being _intentionally_ dense.
Of the set of all objects which are causes for spontaneous combustion, some of them apply to manure. Some of them apply to hay. Some of them apply to oily rags, and so on. Oily rags are not cow manure. Sawdust is not oily rags. Wet hay is neither.

I've noticed that.

I have plenty of respect for science, communication, and learning. You continue not to exhibit any of those.
Third time: (I bet you'll evade it again) Are you saying that spontaneous combustion of sawdust is impossible?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
George wrote:

That's quite a brash statement (that they outgas the same). But I like the way you make brash (or ambiguous) statements and then mock everyone who disagrees. It makes the internet worth while.
Anyway, to the matter at hand...a cursory search of the internet, which as we know never provides false information, shows many examples of spontaneously combusting sawdust, albeit usually at the bottom of a 20' mound. I did, however, find an example of a fire caused by a "pile of sawdust under a sawbench." How big a pile? I dunno'. See:
<http://www.news-mail.com.au/news/0603/280603_2.html
Likely, the dust was from green wood.
-----
Now, because of the nature of the danger, this problem has actually been studied (believe it or not, we need not concern ourselves with hay fires!). The following absolute truth was also found on the internet:
From <http://www.ciwm.co.uk/mediastore/FILES/10867.pdf :
"As with compost and rubber tyres, wood chips and sawdust material can undergo self-heating reactions, leading to spontaneous combustion, under certain storage conditions. Factors that will play a part in whether self-heating leading to combustion will occur are the size of the wood chips, the moisture content, the presence of other flammable waste materials within the stockpile that are easily ignitable, and the natural oil content of the wood. Sawdust has been tested extensively[1] over any years and it has been found that the greater the proportion of oil present in the wood, the lower the critical ignition temperature (the temperature at which a runaway reaction occurs)."
1. Bowes, P C. Self-heating: evaluating and controlling the hazards. Building Research Establishment. Department of the Environment. 1984. HMSO.
It seems this Bowes fella' made a career out of this stuff. Even though he died in 2001, he was nice enough to write it all down in a book. Sadly, now that I'm no longer a student, I can't get my hands on it easily. But maybe if one of you could find it, it could settle the matter of whether or not s.c. is possible in this case. It might also answer the more immediate question of who can piss farther.
In the above, I note the following:
1) Oil content is critical. How much oil is in sawdust from green wood vs. dust from air dried vs. kilned, I don't know. Anyone?
2) Note that several other factors, including other oil sources are important. This certainly has bearing on the original poster's question. Does, for example, it make a difference if he cuts plywood or any other source of organics? What if he hacks up an old project that was treated with linseed oil?
I suspect that if one read the book, you'd be hard pressed to make a case for s.c. at this small a scale (especially since the water content must be just right); nevertheless, I bet you _could_ come up with a scenario, albeit unlikely. Would I worry about it? No. But I'm not silly enough to put water in my DC system...
-----
As for hay, I found this incontrovertible evidence (of course, because it's on the internet):
From <http://www.cdc.gov/nasd/docs/d000701-d000800/d000758/d000758.pdf
"Hay fires usually occur within six weeks of baling, but they may occur in hay several years old. Fire can occur in loose hay, small bales, large bales or in stacks. The fires can occur in hay stored inside as well as in hay stored outside. Regardless of when or where the fires occur, the most common cause is excessive moisture."
Note that "old" hay is also subject to s.c., the point being that once dried, s.c. is rare because, well, it's dry. But if re-wetted, I see no reason why bacterial growth can't restart. Of course the C:N ratio of wood is so high that it's hard to get a lot of bacterial growth and heat production, but that obviously happened in the s.c. examples above. I have certainly felt warmth in sawdust piles, but they were outside where heat/organics couldn't build up enough for s.c.
Anyway, the point is that if you want to claim that hay and sawdust outgas the same, then if old hay can s.c., then surely you agree that old sawdust can, too. Yes?

Well, of course there is. But if we don't understand _all_ of the factors involved, then changing the input (cause) may lead to an unexpected result (effect). That is why scientists have jobs -- because not everything is understood.
Enjoy,
Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
G. Lewin wrote:

There's also how much oil in one species vs another, say Southern Longleaf Yellow Pine heartwood vs some comparatively oilless species, and the composition of the oil--Lapacho for example is about as combustible as concrete, despite being oily enough that you can polish it with its own secretions.

--
--John
Reply to jclarke at ae tee tee global dot net
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Do you have any record of spontaneous combustion coming about from dried wood, subsequently rendered wet as he describes? Don't think it happens.
rhg
J. Clarke wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Robert Galloway wrote:

I'd rather not find out the hard way. Spontaneous combustion _can_ occur with _dry_ wood but it takes a big pile. Get a little rot going and who knows--that's pretty much the mechanism by which haystacks catch fire after a rain. While spontaneous combustion is the topic of a certain amount of research I don't think it can be described as a perfectly understood phenomenon.

--
--John
Reply to jclarke at ae tee tee global dot net
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
J. is not a scientist, but a believer.
You are correct in assuming that it is the oxidation of volatile organics -exothermic reaction - in confinement which causes ignition. They are not normally found in seasoned wood.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Have you ever tried to bathe a cat?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mark Hopkins wrote:

Flashed on a friend who loved cats and loved his wife, who was allergic to cat dander. Solution--remove the dander. So once a week he bathed six cats. Surprisingly, the cats got to where they liked their bath, would line up to be bathed, and became petulant if he didn't bathe them on time.

--
--John
Reply to jclarke at ae tee tee global dot net
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

When I was growing up, our cat felt the need to supervise people baths. Sitting right on the edge of the tub. With his tail dangling _into_ the water.
I don't recall ever finding out his opinion of a -cat- bath. But he did like to be _vacuumed_. Directly by the hose of a regular canister vacuum.
We also had a big Chesapeake Retriever who would 'shake' _on_command_ -- no, not 'shake hands', though he did that too, but after a bath. We would tell him 'stand still', tent a big towel over him, and say 'Okay, _now_ shake', whereupon he would. Was also _real_ handy when bringing him in from outside when it was raining or snowing.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Robert Bonomi wrote:

Never encountered a cat that wouldn't run in terror from a vacuum. OTOH, the neighbor's cat used to like to come over and get swept with a broom.

Probably a big surprise for those who can't resist giving orders to somebody else's dog too.
--
--John
Reply to jclarke at ae tee tee global dot net
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

What can I say. The cat was practically bigger than the vacuum was. <grin> Anyway, he'd just lay down on his side, and when one side was done, he'd roll over.
I don't remember how he got _introduced_ to it, but this was an _old_ green Eureka canister. It was extremely quiet, despite having a lot of pulling power. Did a _great_ job of pulling out the old winter under-coat, come spring time.
I gotta tell ya, vacuuming the livestock is a whole *lot* more efficient than having to vacuum all the furniture, rugs, etc. to pick up shed hairs.

Chesapeake's are *smart* -- _ANNOYINGLY_ smart. However, in this case, he knew the difference between 'sit' / 'shake', and 'stand still' / 'now shake'. Heck, for 'shake' (hands), if you put out your left hand, he'd use his left paw, and if you put out your right hand, he'd use his right paw. And if you then said 'the other one' he'd drop whichever paw he had up, and offer 'the other one'.
The 'stand still... OK, now shake' DID impress the hell out of any visitors who happened to see it -- almost invariably the reaction was "I wouldn't have believed it, if I hadn't seen it with my own eyes!"
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

to
time.
the
vacuum.
<grin>
under-coat,
_on_command_ --

would
somebody
he
shake'.
left
you
'the
visitors
i shower my 4 cats pretty regularly. with 2 of them, i have to bang them pretty good with the vacuum to get them to move. they're not afraid of it at all and must think i'm pretty annoying when i want them to move.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.