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Boiled Linseed Oil


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Because it forms a water resistant coating which will inhibit rust but won't rub off easily like other oils..   Boiled Linseed oil will dry faster than Linseed oil..  Boiled linseed oil will also fill in the voids or small cracks (penetrate) in forged work where a lot of paints will not.. I have also found that certain paints for some reason never really seem to have closed pores and water despite all the proper prep still rusting is  a problem.. 

Cosmoline is  a great product for long term storage but not so good when handling the items.. 

If the item is hot when applied (left in the sun) it will dry faster..  

This information is from my experience over the last 40+ years.. 

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I think it is an old time preservative.   wiped on sparingly and allowed to dry, it polymerizes and leaves a hard finish.  I've found that after I wipe off the excess after an hour or so and let it dry for a couple days it is a hard non sticky coating.  if there are still sticky spots, wiping with a wd-40 rag will clean it off.   I think the short answer is that it works.



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I've always just given the anvil a wipe with clean and new 5w30 motor oil.  After every forging session I just give the anvil a good wipe-down.  When I clean up tong purchases that are all rusty, I do the same thing after the wire brush wheel on my angle grinder.  I've never seen the rust come back and my tools are in a basement workshop where anything rusts if left around there too long.

I think it's one of those things were many different things work, some better than others.  For me, it's just cheaper and easier to do the wipe down with oil I have around the shop.  I think as long as you are keeping things from rusting you are accomplishing the goal.  With all that said, rusty anvils still move metal :D  For me though, I've always felt that rusty tools give the wrong impression to those who don't know anything about what we do.  I'm of the camp that says "Take care of your tools and they will take care of you."

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There is a difference between the face of an anvil and the rest of the anvil when it comes to protection from the elements and rust.

There should be consideration given to frequency of use. Daily or weekly use is a lot different from using it again in 3 months, 6 months, or a year from now. Consideration should be given to the environment in which it is used. Inside a building, inside a barn, and outside under a shelter are all very different. The geographic location, desert, mountains, and near large bodies of water or salt water should be considered.

Be sure what ever you use works and can be renewed when it is needed. 

There is no one right answer, just what works for you in your location.


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Boiled linseed oil polymerizes and makes a hard finish. As Jennifer says it's a penetrant and gets in everything, especially if applied to a warm surface. Folks recommend it because it works well and has done so from times of old. Maybe Thomas will tell us how long it's been around. 

I still like Trewax it's a strong penetrant when applied to a hot surface and cools to a hard finish that won't wipe off. The main difference is how long you have to wait. 

Yes. wipe off the excess, I keep a couple rags in the can of wax, they carry plenty to finish. If they get too dry I dip the warm piece in the can, it gets drippy coated and I wipe it off with the rag. Nice thin coat on the piece and the rag is ready again. 

Don't allow rags with boiled linseed oil to collect, they are a serious fire hazard. I don't recall if it's the boiled or unboiled that can spontaneously combust on it's own over time. I don't remember so I don't keep any oily rags or brushes. If the rags in my wax can combust it can't go anywhere it's a sealed can.

Frosty The Lucky.

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Both boiled and  'plain'  linseed oil can spontaneously combust given time and the right conditions.

Linseed oil does little drying.  The oil slowly polymerizes.

But the real villain is the slow oxidation of oily rags.  Heat builds up and the combustion temperature is reached.  (i.e.  the flash point).

And then  FIRE!

There are safety measures that we can use to avoid unwanted conflagrations

We can promptly discard the rags (& other oily material),

or store the material in a well ventilated place,

or store them in a heat resistant and air sealed container.  (i.e.  no oxygen  so no oxidation).  The air in the container is used up and the reaction stops. 


p.s.  The oil does not dry. It polymerizes.  The fatty acids in the linseed oil,  (a.k.a., as flax seed oil),  hook up head to tail to form very long strands.  Just like the plastics we use.

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Before discarding the rags, hang them up individually ,(or spread them out flat) to dry, preferably outside They can then be thrown out safely.

4 hours ago, SLAG said:

The oil does not dry. It polymerizes. 

The oil itself, yes. However, many (even most) commercial linseed oil products contain some amount of volatile thinner that needs to evaporate out before the polymerization can start.

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Great information you provided.

Here are a few more tit-bits.

Some of the "processed linseed oil, (boiled oil, stand oil etc.) have drying agents in them that speed up "drying" of the oil.

These siccatives frequently, use heavy metals to accomplish that task.  Metals such as cobalt etc.

Which prevents that oil's use for eating purposes.  It makes them poisonous.

You can speed up that process and avoid heavy metal additives,  by putting the oiled object in a sunny place,  preferably outdoors.  Heat will also speed up the process.


p.s.  An alternative to throwing the oily rags out is to use them as fire starter in the forge.  They burn fiercely,  and work very well.



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I never use straight boiled linseed oil for a finish. It is too riskey due to the long time needed for drying or polemerizing. 

For a good traditional finish, I use blo, turpentine, and beeswax. I Mix Blo/turps 50/50 and if I use a quart of each, about a walnut size piece of beeswax. Apply at a black heat.  When it smokes off and leaves your iron black, its the right temp. The turps thins the blo and is pretty important as far as I'm concerned. The proportions are not too critical. For a padte instead of a liquid, add more beeswax.

For a cold finish, substitute the beeswax for "a healthy pour" of japan dryer. The japan dryer is a drying agent and if you are doing a 10' rail, it will be dry and ready for another coat by the time you get back to the beginning. It takes very little time to "wipe on/wipe off this finish. Keep your container closed as the japan dryer will evaporate. Add more as needed.


After applying either, my next step is to clean my work with denatured alcohol. Regular alcohol will leave a film. This removes any and all forge/oil/ or just plain "gradoo" from your work. It also starts a burnishing process that's a plus.

My final step is to buff it with a carnuba based wax like tree wax, johnsons paste wax,or a good carnuba baded car wax. This buffing enhances the burnish.

This process is clean enough that when their daughter is promanading down the stairs with her dainty white gloved hand on yer cap, her glove will stay white. Not to mention the surprise your cabinet maker will have when he gets black streaks on his brand new oak cabinets when he hangs yer hinges and pulls.

plain ole boiled linseed oil will rarely pass this test, no matter how long it has been drying or polymerizing.

Of course, you could always take the chance...  ;)

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On 9/15/2018 at 8:17 PM, MotoMike said:

does it dissolve

I heat it on the forge in an old metal paint can...  with lid and handle.

Raise the heat slowly, and if it flashes, just use your rake or poker to move it off the fire and put the lid on. I then pour the mix back into the quart cans.

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When I make the beeswax, BLO and turpentine mix I make it in an junky pot on the electric stove. ( dont use a good cooking pot)  1 part beeswax shaved with a knife into the pot. Once melted I add the 1/2 part BLO and 1/2 part turpentine, mix and pour into a cookie tin and let cool. 


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Thank you for your excellent description for making a BLO, turpentine and bee's wax mixture.

Permit me to offer two suggestions.

Heat the container with said mixture in a double boiler set up.  That will limit the heat build-up to a temperature well below the flash point of the ingredients. In other words it is less likely that the mixture will not catch fire.

Do not walk away while heating the mixture.  Especially in the beginning,  when the turpentine vaporizes

If a double boiler set-up is used  you can substitute,  a cleaned,  empty can for the container.  A large can of Campbell's soup is excellent for this purpose.

In a pinch,  another, emptied can will work. almost as well.

Regards  to all,


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20 minutes ago, SLAG said:

If a double boiler set-up is used  you can substitute,  a cleaned,  empty can for the container.

The can you store your finish in is a good option. Just stir well when everything is melted, and put the top on when it's cool.


20 minutes ago, SLAG said:

In other words it is less likely that the mixture will not catch fire.

I think you mean either "more likely that the mixture will not catch fire" or "less likely that the mixture will catch fire".

(At least, I hope that's what you mean. Let's not set Daswulf on fire.)

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Good add ons.  I didn't have any issue with just using the metal pot since only enough heat is used to melt the wax, so a low heat. Tho a double boiler would work safer. 

When its done/ cooled, it will be able to be wiped on with a rag but if stored without a lid it does harden up a bit where I'll take the piece to be coated at a warm temp and melt the wax a bit with it then wipe on and off with the excess. Keep it sealed when not in use as long as you can. 

I'd prefer not to get set on fire. ;) I dont smell too good when burnt.



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3 hours ago, SLAG said:

A large can of Campbell's soup is excellent for this purpose.

you need a lid or the turps will evaporate. just adding to what's already posted.  ;)


2 hours ago, Daswulf said:

I didn't have any issue with just using the metal pot since only enough heat is used to melt the wax, so a low heat

Besides, it isn't going to explode, just flash. Keep the temp down and you wont have this problem. Besides a double boiler adds clutter to yer shop and takes too long. Safety first includes an oz of caution to the process, not just more stuff.

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The can is only used to melt and combine the ingredients.

After the mixing is complete it should,  I would then,  transfer the lubricant to an air tight container.

I strongly recommend that neither the container nor the cover be made out of plastic.

Some plastics are dissolved by turpentine. We don't need the ensuing mess nor loss of product.


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