[Cob] linseed oil

[Shannon Dealy]

> On Jul 22, 2010, at 10:14 AM, Tys Sniffen wrote:
>
>> Anyone have brand/store recommendations for linseed oil for floors?
>> 
>> I know about the additives that create the 'boiled' vs raw, but I can't
>> really find good comparisons between the 'truly boiled' and 'chemically
>> boiled' oils. has anyone actually found the additives to be a problem? Or 
>> is
>> that just philosophical?

Raw linseed oil is not a drying oil, it will remain permanently sticky 
(until enough dust or other crap covers the surface).

Boiled linseed oils to the best of my knowledge are all actually boiled, 
however, to speed drying times toxic chemicals including heavy metals such 
as lead are added to the common commercially made "boiled" linseed oils.
The less toxic alternative versions usually at least leave out the heavy 
metals, though they may require longer times to cure as a result (I've 
never looked into the chemical reactions involved).  Usually figure 48 
hours minimum drying time for a thin coat with the toxic versions at room 
temperature.  I don't know the cure times for the "green" alternatives 
though I expect they would say on their web sites.  Curing time can be 
reduced somewhat by increasing the temperature and/or air flow, though I 
would recommend avoiding anything which might ignite the fumes.  I just 
finished rebuilding an earthen floor sample I use for show at a local 
festival and did a quick cure of several coats of oil by cooking it 
under the back window of my car in the summer sun.

FWIW.

Shannon C. Dealy      |               DeaTech Research Inc.
dealy at deatech.com     |          - Custom Software Development -
Phone: (800) 467-5820 |          - Natural Building Instruction -
    or: (541) 929-4089 |                  www.deatech.com