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Re: Cleaning Shop Rags

To: shop-talk@Autox.Team.Net
Subject: Re: Cleaning Shop Rags
From: Jim Van Hooser <jvanho01@tir.com>
Date: Thu, 23 Jul 1998 06:29:23 -0400
I must say that this certainly puts a new light and importance to the issue of 

oily rags and letting them lay about.  I am not only into cars but also into

woodworking and am guilty as heck of using tung oil, etc.. and then leaving the

rag in a heap or worse yet in a metal trash bucket with other rags.  I guess I

have just been lucky up to this point, but this is a practice that I will quit

doing right now.


Now this does bring up the matter of how to dispose of these rags safely.  



Jim V.


At 08:51 PM 7/22/98 +0000, you wrote:

>

>Self combustion from "oily rags" is a real threat, but not from petroleum 
>soaked 

>rags.  Oils which can result in spontaneous combustion are linseed and tung 
>oils, 

>(there may be others, but I do not know of any).  The reason that linseed and 
>tung 

>oils are used on wood (as a finish or combined with dyes as a stain/finish) is 
>that 

>they polymerize (sp?) in a process combining with oxygen in an exothermic (ie: 

>released heat) reaction.  So, lets say that you soak a rag with on of these 
>oils and 

>spread it on some wood, then drop the rag in a heap and go take a lunch break. 
> The 

>oil on the wood begins combining with oxygen and begins both hardening and 
>releasing 

>heat.  The amount of oil on the surface of the wood is pretty little and the 
>surface 

>area is large - hence no noticeable rise in the temperature of the wood 
>surface and 

>no risk. The rag on the floor, however, has a large amount of oil saturating 
>it and 

>the temperature begans to rise.  The speed of chemical reations (like the oil 

>combining with oxygen) doubles with every 10 degree F rise in temperature. So 
>as the 

>rag warms up, the chemical reaction speeds up warming the rag faster and 
>faster.  If 

>the temperature rises high enough one can get smoke and eventually flames.  
>There is 

>a house not too far from where I live which burned down to the ground a few 
>months 

>ago from a wood staining rag igniting in the middle of the night. 

>

>I am not a chemist either, but I don't think that any oil which is stable in 
>air can 

>cause spontaneous combustion.  If the oil skims over in a can and hardens on 
>contact 

>with air, be careful.  I don't think that common cooking oils are a concern.

>

>-Roger

>

>

<bold><italic><color><param>0000,0000,8080</param><bigger>Jim Van 
Hooser

jvanho01@tir.com

</bigger></color></italic></bold>

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