Boiled Linseed Oil is a popular topic on this list. Its something we all swear
by and at.
Here are some of my ramblings on the topic. Worth the coins off a dead mans
eyes. (tuppence, Paddy)
Way back when, BAWI - (Before America Was Invented) using the oil from
Linseed was a good way of getting a finish onto wooden artefacts. The thing
about LO is that it naturally polymerises. That's modern speak for 'it dries' -
unlike olive oil, which doesn't.
If you want your refectory table to resist the ingress of nasty stuff that goes
rancid or leaves unsightly stains you give it a coat of something - wax is good,
and comes in handy, self replenishing packages called skips. Painful to collect
unless you know how to dispossess the original owners. Linseed oil is better
than wax though, as it doesn't come off as easily, once hard.
Back in the xxth Century there was plenty of time and manpower, so applying lots
of coats and waiting may not have been as costly as it is today.
Roll forward to the Victorian age, and them scientists work out that oxygen
makes oil set faster, so to get the polymerisation started you can blow air
through, and a bit of heat kicks it off nicely - so boil it. Then use it up
before it goes off
Roll forward a bit more, and we start adding other stuff that makes it dry
faster and harder. You can stop drinking it at this stage, in fact you'd better
stop drinking it, or using it on food related products like chopping boards and
salad bowls. Yes, you could eat off oiled salad tongs / bowl for years with no
bad things happening, but, well, we've been making about a thousand 'new'
chemical products a year since the fifties, and stuff like DDT was a good thing,
and thalidomide, and we didn't know that Coca Cola would bring down a whole
generation of kids and reduce them to heaps of overweight diabetics and so on.
So swap to pure walnut oil or food grade linseed oil, and stop drinking the BLO.
If you really want to make your own BLO, then first find some oil, then boil it.
at a high temperature. for a long long time.
Or wait longer if you use the raw stuff.
When Scott said that raw LO doesn't dry, he also qualified it and said 'nearly'
because he knows that it will dry, but maybe not in your lifetime, and
especially so if you allow it to capillary its way into the interior of timber,
where there is no oxygen to cause it to polymerise. That timber will weep for
years to come every time the ambient conditions make it expand/contract /
spring a leak. BLO, however, already has the reaction in progress, so will
eventually get there.
The story about dunking a new plane is probably true. If there are no heavy
planes, because there are no iron planes, how're you to make a good heavy tool?
add weight - fill it with oil.
I love oil finishes. 20 or 30 coats produces the finish that predated french
polish (shellac) - oil the product a few times over a couple of weeks, deliver
it, and then wipe over with an oily cloth every week for a year, every month for
ever. Well, these days maybe not. Maybe take the Scott G shortcut and apply as
many coats as you have time for, then a mix with a harder, oil friendly varnish,
or if you have enough coats, go back to the 17th century and apply wax. BLO and
wax - a very forgiving finish that can be repaired easily.
Richard Wilson
Yorkshireman Galoot
in Northumberland, where autumn just arrived.
More about oils
http://books.google.co.uk/books?id=Zb84fVthd_cC&lpg=PA335&ots=bE4YH3sTZ
M&dq=%22Rape%20seed%20oil%22%20%2B%20polymerise&pg=PA335#v=onepage&q&f=false">ht
tp://books.google.co.uk/books?id=Zb84fVthd_cC&lpg=PA335&ots=bE4YH3sTZM&dq=%22Rap
e%20seed%20oil%22%20%2B%20polymerise&pg=PA335#v=onepage&q&f=false
On 16 Oct 2014, at 08:09, Malcolm Thomas wrote:
> Oh, just so that I am 100% clear here - when you all refer to BLO, you are
referring to the over-the-counter bottled BLO you buy in the hardware store ??
or, are you guys actually boiling your own linseed oil - because we simply like
the old ways :-) ???
>
> Sorry for the GIT-ish type question..
>
> Cheers
> Mal
>
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