Linseed oil and linseed oil paint

[deema]

I was reading a recent reply to a post where it was stated that linseed oil offers very little to any protection against the weather. This is not the first time I’ve read this and I can’t help wondering what really is the case.

Linseed oil paint has in most cases three constituents from my reading, linseed oil (majority) a pigment and a dash of natural turpentine. The pigment doesn’t seem to offer any weather protection and the only component that could offer protection is the linseed oil. I know that originally lead was added to most paint which killed of any fungus etc but has been banned for a long time. So modern linseed oil paints use titanium dioxide for white which is also very toxic. There are numerous testimonials to linseed oil paint lasting c15 years with only the occasional paint over with linseed oil.

Does anyone know what the weather protection properties are of linseed oil? I find it offers as good protection as most things, it just has no UV protection so things fade or go dark depending on species.

 

[thetyreman]

from my non academic research, I found that pure tung oil is far superior at rejecting moisture and mould e.t.c, but I don't know how much of this is snake oil and how much of it is real science.

 

[deema]

I agree, I’ve used pure Tung oil on oak which works well.

 

[Jacob]

Linseed oil paint is totally superior to modern paints in terms of durability. It was marketed by Holkham Hall but now available from others. Brand name "Allback"
http://www.allback.aannemer-nijland.nl/ ... engels.pdf
Not sure about oil on it's own but I'd be surprised if it didn't work just as well, though oil finishes need more regular maintenance than paints. It's very easy to apply.

 

[deema]

Thanks Jacob, all of the recipies I’ve found for linseed oil paint consist of linseed oil and a pigment with perhaps a little thinner, usually natural turpentine. I know you and lots of others have had great success with the paint, and originally it was extensively used and worked as folk law suggests better than modern paints. The only two real draw backs being it’s difficult to apply thinly enough to avoid crinkles and runs and the other that it takes ages to dry. Both of which make it not really a DIY product when compared to modern paints.

The point being that linseed oil as a external preservative has a very poor reputation when applied without a pigment (making it a paint). To apply it correctly, like the paint is difficult as you can end up with crinkles and worse still a sticky mess that will not set. However, that aside the question phrased slightly differently is why is the paint considered a ‘miracle’ finish and linseed oil not?

 

[Jacob]

......The only two real draw backs being it’s difficult to apply thinly enough to avoid crinkles and runs and the other that it takes ages to dry. Both of which make it not really a DIY product when compared to modern paints. ...

I'd say exactly the opposite. It's very easy to apply thinly - no skill required at all though it helps if you can do a clean edge against glass etc.
You just have to get away from the modern paint technique of laying on nice smooth layers. Instead you brush it on with a stiff brush and brush it out thin enough so there are no pools, runs etc. More like applying creosote than painting and very fast!
It takes 24 to 48 hours to dry. It seems to stay wet for some time and then goes off quite quickly.
For DIY it's a lot easier in every respect - easy to put on, needs no thinners, easy to wash off your hands with soap and water, easy to leave the brush suspended in oil until the next time, or wash it out in the normal way with thinners or brush cleaner. No VOCs etc.
It will need more some years down the line but this is easy - wash down with soap and water and apply oil alone, or paint if it needs it. No need to burn off and it doesn't flake off or crack.
It also seems to stick well to old paint and effectively stabilises it, so burning off becomes a thing of the past. NB recent past that is, it was never done in 19C when paint was all linseed oil.
I've been using it for 10 years or so and now won't be using anything else for exterior work.

 

[tony_s]

I tried it about 5 years ago on my garden sheds and have used it since on a couple of other exterior projects and absolutely love it. The only downside imho is the drying time.

 

[ED65]

Linseed oil paint has in most cases three constituents from my reading, linseed oil (majority) a pigment and a dash of natural turpentine.

It's a little more complicated than that. There are permissible stabilisers and other additives (fungicides being an important one) can be included in very small amounts and the industry may not have to mention or list it/them – in fact manufacturers sometimes go out of their way to obfuscate and even lie about them being present – but at the most basic linseed oil paint can be just oil and pigment, although rarely just one.

Paints today will rarely contain turps but some form of white spirit instead, although it doesn't really matter which is used as they're just there to thin. Any paints that do use turpentine will probably do so because of its apparent green credentials or because they can make the claim that their paints are "all natural" (another lie).

The pigment doesn’t seem to offer any weather protection and the only component that could offer protection is the linseed oil.

No that's completely wrong, the pigment(s) offer a huge amount of protection not just to the wood underneath (literally because it shields it from light) but also to the paint/coating itself.

Paint made from linseed oil and linseed oil by itself shouldn't be expected to have similar properties. The binders of no paints, by themselves, are anything like the paints made from them in various ways.

The pigments in paint, because they're often mineral particles that are opaque, and additionally absorb some light frequencies, impart a HUGE amount of protection to the binder. The simplest example of this is probably alkyd varnish, which isn't durable outdoors, but make up an enamel from it by adding pigment and it can last years.

...titanium dioxide for white which is also very toxic.

I'm not sure what sources you've been reading but TiO2 isn't toxic at all. It's safe enough that it's used in toothpastes, but even better it's used to colour many oral medicines, even in foods!

Does anyone know what the weather protection properties are of linseed oil? I find it offers as good protection as most things, it just has no UV protection so things fade or go dark depending on species.

It depends a bit on the version, what you're applying it to, its condition and how you apply it. But the bottom line is for our climate it's just not a viable wood finish for exterior use. By itself it can work reasonably well, but only in a drier climate and when applied quite heavily, taking weeks to dry.

 

[Jacob]

...... By itself it can work reasonably well, but only in a drier climate and when applied quite heavily, taking weeks to dry.

Basic linseed oil mistake there! It works best if applied very thinly and takes 24/48 hours to dry, even in cold/damp weather. It oxidises - it doesn't "dry" strictly speaking, but yes heat will speed it up.
First coat slowest (soaks in etc) but later coats very quick and easy to apply. No skill required.
I haven't done much oil alone externally, but the paint works brilliantly so I'm staying open minded on oil alone.

 

[Jacob]

Basic linseed oil mistake there! It works best if applied very thinly and takes 24/48 hours to dry, even in cold/damp weather. It oxidises - it doesn't "dry" strictly speaking, but yes heat will speed it up.
First coat slowest (soaks in etc) but later coats very quick and easy to apply. No skill required.
I haven't done much oil alone externally, but the paint works brilliantly so I'm staying open minded on oil alone.

Just having linseed oil paint top-up job done.
This is on 16 very large chapel windows, softwood mostly new (copy) work and some repaired. Last painted between 7 to 12 years ago.
Verdict on the paint - was looking a bit dull but absolutely zero rot or flaking. A few inches of putty fillet loose/ missing.
Verdict on the repaint - very easy to do, probably unnecessary but looks a lot brighter. Not much paint used up. Should last even longer than the first job!
In other words Allback linseed oil paint is excellent and does what it says on the tin!
A great relief - in the past I've had dreadful failures with Dulux, ali primer etc and feared for the survival of this massive softwood restoration job.
No problems! Phew!
PS rumours of mildew unfounded. Non apparent. Did get it on some doors last year but that was after an oil-only top-up but with another brand. Allback say "sterilised" so maybe that makes the difference.
n.b. I've no connection with Allback etc - never even a free sample!

 

[Inspector]

Just for clarity are you talking of raw linseed oil plus pigments etc or boiled linseed oil used to make the paints?

Pete

 

[Jacob]

Just for clarity are you talking of raw linseed oil plus pigments etc or boiled linseed oil used to make the paints?

Pete

Raw linseed as a primer and paint made with boiled linseed and pigments.
1344ae24-8229-4f01-851a-7645ad9ce96a seem to be the only UK source though there have been other suppliers.
The downside is limited range of colours tending to be a bit dull, and an eggshell/ matt finish. No high gloss means less easy to clean quite so perfectly, though presumably it could be varnished in the traditional way

 

[Inspector]

Thanks. The Allback (at Lee Valley) sells for $82.50Cad/53pounds a litre so before I consider using it for anything big like a house I would need a lot of proof it is as good as claimed in our climate. Maybe there are cheaper sellers here but the cost and work makes me happy the house is all vinyl. That's the only reason though.

Pete

 

[Jacob]

Thanks. The Allback (at Lee Valley) sells for $82.50Cad/53pounds a litre so before I consider using it for anything big like a house I would need a lot of proof it is as good as claimed in our climate. Maybe there are cheaper sellers here but the cost and work makes me happy the house is all vinyl. That's the only reason though.

Pete

There are other suppliers but probably not cheap. It does go a long way though and is easy to apply. I think its good value when you take everything into account. Pure Linseed Oil Paint
Main thing is longevity - given good design and normal maintenance softwood joinery can last indefinitely and outlive plastic by 100 years or more!

 

[Kittyhawk]

I use boiled Linseed Oil exclusively on my Inuit style kayak paddles using the time honoured method of one coat a day for a week, one coat a week for a month, one coat a month for a year and thereafter, one coat annually. A paddle is subject to frequent immersion and scuffing and boiled Linseed Oil holds up exceptionally well - far better than varnish.
Application is very simple. Apply with a rag, brush or whatever. Leave for 20 minutes then rub down vigorously with a cloth to remove the surplus oil.
Here is my walking stick, made from some hardwood or other that I had on hand. I use it daily in all weathers and it was last recoated with oil 2 years ago.

 

[pgrbff]

Thanks Jacob, all of the recipies I’ve found for linseed oil paint consist of linseed oil and a pigment with perhaps a little thinner, usually natural turpentine. I know you and lots of others have had great success with the paint, and originally it was extensively used and worked as folk law suggests better than modern paints. The only two real draw backs being it’s difficult to apply thinly enough to avoid crinkles and runs and the other that it takes ages to dry. Both of which make it not really a DIY product when compared to modern paints.

The point being that linseed oil as a external preservative has a very poor reputation when applied without a pigment (making it a paint). To apply it correctly, like the paint is difficult as you can end up with crinkles and worse still a sticky mess that will not set. However, that aside the question phrased slightly differently is why is the paint considered a ‘miracle’ finish and linseed oil not?

The pure linseed paint I use has no thinner as far as I know and I also choose the version without driers. If it wrinkles it is being applied incorrectly. I have only used it over sweet chestnut, inside and out, but it is very thoroughly brushed out. I only apply one coat.

 

[Jacob]

The pure linseed paint I use has no thinner as far as I know and I also choose the version without driers. If it wrinkles it is being applied incorrectly. I have only used it over sweet chestnut, inside and out, but it is very thoroughly brushed out. I only apply one coat.

Allback - no thinners but includes a drier. Add boiled linseed oil if thinning required. Is actually easy to apply brushed thinly and requires very little skill at all except keeping a neat edge against the glass. This also accounts for its good coverage.
It seems to stick to everything - just one coat (black) needed on some wrought iron gates, and covering patches of previous paint left after a rub down.

 

[pgrbff]

The brand I use. reine Leinölfarben, is available with or without driers. I always buy without and in our climate it still dries within hours.

 

[Jacob]

I use boiled Linseed Oil exclusively on my Inuit style kayak paddles using the time honoured method of one coat a day for a week, one coat a week for a month, one coat a month for a year and thereafter, one coat annually. A paddle is subject to frequent immersion and scuffing and boiled Linseed Oil holds up exceptionally well - far better than varnish.
Application is very simple. Apply with a rag, brush or whatever. Leave for 20 minutes then rub down vigorously with a cloth to remove the surplus oil.
Here is my walking stick, made from some hardwood or other that I had on hand. I use it daily in all weathers and it was last recoated with oil 2 years ago.
View attachment 137669

I've done same process on a sanded down mid century modern table top, but with raw oil. Very quick to apply and rub down but a long wait for a good finish - probably did about 10 applications. It looks really good, not too shiny and brings out the colour of the teak, afromosia etc

 

[Jacob]

The brand I use. reine Leinölfarben, is available with or without driers. I always buy without and in our climate it still dries within hours.

Looks interesting! Home