Tung over Linseed Oil?
- Thread starter cuervo
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If you do that you are going to have neither... you are going to have a mix. Take off some hardware and see if you can find a small spot to dab on some tung oil... like under the recoil plate/pad. There is often some dripped in there.
What is the condition of the stock? Why do you want to cover over it?
What is the condition of the stock? Why do you want to cover over it?
Mark whiz
Member
It won't hurt a thing to put one over the other. In fact, if you want you can mix the 2 together and rub them in that way.
the naked prophet
Member
Tung oil will remain sticky and will "grab" dust. Why would you rather have Tung oil than Linseed oil?
I've refinished several M1s with tung oil and have never had a problem with it not drying. It seems to make a harder, more durable finish than linseed oil.
If anything, it seems to me that my hands always end up smelling like linseed oil after handling a rifle finished that way.
The rifle in question has already been finished in linseed oil and I didn't want to have to refinish the whole stock to have a tung oil finish. There's nothing wrong with the stock other than the fact that I prefer tung oil finish rather than linseed.
If anything, it seems to me that my hands always end up smelling like linseed oil after handling a rifle finished that way.
The rifle in question has already been finished in linseed oil and I didn't want to have to refinish the whole stock to have a tung oil finish. There's nothing wrong with the stock other than the fact that I prefer tung oil finish rather than linseed.
W.E.G.
Member
I've had good results with tung oil.
If you have trouble getting tung oil to dry (I never have), you might try using some Japan Dryer to speed up the process. If you have a warm workshop, and you aren't in a big hurry, you probably will have no need for drying accelerants.
Tung oil will NOT spontaeously combust.
Linseed oil WILL spontaneously combust.
I even won't allow a container of linseed oil to enter my house.
Just not worth the fire danger and the hassle.
http://www.allprocorp.com/techbuls/SunnyTB/7590TB21035BldLnsdOil.cfm
and
http://en.wikipedia.org/wiki/Linseed_oil
CAUTION: Oil soaked materials may spontaneously ignite.RISK OF FIRE FROM SPONTANEOUS COMBUSTION EXISTS WITH THIS PRODUCT. Linseed Oil generates heat as it dries. This heat generated as it dries can cause spontaneous ignition of materials contacted by Linseed Oil. Oily rags or waste and other oily materials can cause spontaneous combustion fires if not handled properly. Immediately after use, and before disposal or storage, you MUST (1) spread out all oily materials outside to dry by flattening them out to their full size in an any spot for 24 hours at temperatures above 40° F, or (2) Wash them thoroughly with water and detergent and rinse. Repeat until you have removed all oil from all cloths, tools, rags, paper, clothing, mops and any other materials contacted during use or as a result of an accidental spill. Make certain all wash and rinse water is disposed of down sink drain.
If you have trouble getting tung oil to dry (I never have), you might try using some Japan Dryer to speed up the process. If you have a warm workshop, and you aren't in a big hurry, you probably will have no need for drying accelerants.
Tung oil will NOT spontaeously combust.
Linseed oil WILL spontaneously combust.
I even won't allow a container of linseed oil to enter my house.
Just not worth the fire danger and the hassle.
http://www.allprocorp.com/techbuls/SunnyTB/7590TB21035BldLnsdOil.cfm
and
http://en.wikipedia.org/wiki/Linseed_oil
CAUTION: Oil soaked materials may spontaneously ignite.RISK OF FIRE FROM SPONTANEOUS COMBUSTION EXISTS WITH THIS PRODUCT. Linseed Oil generates heat as it dries. This heat generated as it dries can cause spontaneous ignition of materials contacted by Linseed Oil. Oily rags or waste and other oily materials can cause spontaneous combustion fires if not handled properly. Immediately after use, and before disposal or storage, you MUST (1) spread out all oily materials outside to dry by flattening them out to their full size in an any spot for 24 hours at temperatures above 40° F, or (2) Wash them thoroughly with water and detergent and rinse. Repeat until you have removed all oil from all cloths, tools, rags, paper, clothing, mops and any other materials contacted during use or as a result of an accidental spill. Make certain all wash and rinse water is disposed of down sink drain.
geim druth
Member
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- Jun 12, 2006
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- 270
Tung oil can get gummy if you leave excess oil soaking on the wood too long. Follow the directions on the can and you shouldn't have a problem.
It's good advice to test on a small, inconspicuous area.
Tung oil does give a prettier, harder finish, but this might not be evident right away. It might take several applications over a period of months before you see a difference.
It's good advice to test on a small, inconspicuous area.
Tung oil does give a prettier, harder finish, but this might not be evident right away. It might take several applications over a period of months before you see a difference.
Huh? I've NEVER had that problem on any piece of wood I've finished with tung oil or with any piece professionally done. Tung oil is a common finish for guitar necks... it's a great satin finish that does NOT get sticky from sweat and hand grime.
I have tung oil on my Garand and it's GTG.
Buzzbox
Member
I haven't ever had Tung come out gummy on any of the stocks I've refinished. Always hard.
If either comes out gummy, the coat was too generous. I apply with a cloth.
Boiled Linseed oil is less durable than Tung, and can yellow. You can certainly apply right over, but I always strip.
If either comes out gummy, the coat was too generous. I apply with a cloth.
Boiled Linseed oil is less durable than Tung, and can yellow. You can certainly apply right over, but I always strip.
W.E.G.
Member
from
http://www.sydneywoodturners.com.au/site/articles/finishing/oils.html
There have been some threads over the last few months, that have debated the relative merits of Tung oil and Linseed oil. In order to shed a bit of light on the complex drying process of these two oils, the following is a general introduction to both oils.
Linseed oil is made from the seeds of the flax plant (Linum usitatissimum L.) Tung oil (aka wood oil, chinawood oil) is made from the seed kernels of the Tung tree (Aleurites fordii). Drying Oils can be defined as liquid vegetable oils that, (applied in thin layers to a non-absorbent substrate), will dry in the air to form a solid film.
This drying, is a result of polymerization by the action of atmospheric oxygen (autoxidation). Two common drying oils are Tung oil and Linseed Oil. The resultant film formed is typically hard, non melting and usually insoluble in organic solvents (this varies with the particular oil).
Nonconjugated oils, such as Linseed oil, are fatty oils that contain polyunsaturated fatty acids, whose double bonds are separated by at least two single bonds. Conjugated oils on the other hand, such as Tung oil, are polyunsaturated fatty acids whose double bonds are partly or fully conjugated.
The place of cultivation and its climate can alter the fatty acid spectrum of a drying oil. The high proportion of linolenic acid in nonconjugated oils (like Linseed oil), affects its drying characteristics. High concentrations of linolenic acid can result in rapid drying, yellowing and brittleness.
Conjugated oils like Tung oil, are considerably more reactive than nonconjugated oils (like Linseed oil). Conjugated double bonds favour polymerization and oxidation and dry more rapidly than nonconjugated oils. The resultant film offers a high resistance to yellowing and increased resistance to water and alkalies.
The principal drying component in Tung oil is eleostearic acid, a conjugated octadecatrienoic acid. The oleic acid contained in the fatty oils and unsaturated fatty acids plays a small part in the drying process as well. The saturated fatty acids present act only as plasticizers.
The drying of films typically progress in three overlapping steps:
1. Induction - through a process known as autocatalysis, the oxygen uptake steadily increases. Factors such as temperature, light and heavy metals/inhibitors in the oil, affect the overall uptake rate.
2. Initiation - as the film continues to take up oxygen, its mass increases. The double bonds in the film begin to rearrange and polar groups such as hydroxyl and hydroperoxy develop in the film. This leads to the association of molecules through forces such as hydrogen bonding.
3. Cross-Linking - As the number of double bonds in the film begin to diminish, larger molecules form and volatile and non-volatile carbonyl compounds are generated.
The exact chemical reactions in these steps, as well as the structure of the film-forming polymers, are not fully understood. The initial autoxidation step in nonconjugated oils (Linseed), is dehydrogenation of the unsaturated fatty acid by oxygen, which forms a radical. This starts a radical chain reaction that increases incrementally with time, leading to the formation of a hydroperoxide.
At low levels, the hydroperoxides produced during autoxidation, decompose to form free alkoxy and hydroxyl radicals. Higher levels of hydroperoxides form free radicals through boimolecular disproportionation. The resultant free radicals react in various ways to accelerate the autoxidation process.
The drying of Tung oil varies considerably from Linseed oil. Tung oil typically absorbs approximately 12% oxygen (Linseed oil absorbs approx. 16%) and quickly forms a skin on the surface. Since less oxygen is absorbed, the viscosity of the oil increases at a faster rate. Unlike the hydroperoxide formation during autoxidation in Linseed oil, Tung oil forms cyclic peroxides. (The methyl eleostearate formed has a higher molecular mass than linoleic acid esters).
The direct attack on the double bonds by oxygen forms cyclic peroxides. The resultant reaction of the peroxides with allylic methylene groups, leads to the formation of radicals. This creates a radical chain reaction, that forms polymers. The molecular mass created is less than that achieved through Linseed oil polymerization. To speed up the film formation, manufacturers add driers to the oils.
Driers are oil soluble metal salts of organic acids. When these driers are dissolved in aliphatic or aromatic hydrocarbons, they are known as siccatives. When driers are added to drying oils, they are known as Boiled Oils. In order to increase the viscosity of the Boiled Oil, air is sometimes "blown" through the oil at 60-100 degrees Centigrade.
Rags soaked with drying oils (treated with siccatives) present a significant danger of exothermic autoxidation, which could lead to spontaneous combustion. Therefore, when working with boiled oils (or other oils treated with driers or siccatives) you must pay careful attention to the safe disposal of any oil soaked rags. The rags should never be folded, crumpled or otherwise compressed, until the oil has fully dried. Proper disposal according to manufacturer's recommendations i.e. fireproof containers, should be used if possible.
The yellowing of Linseed oil is caused when conjugated unsaturated hydroperoxides are converted into conjugated unsaturated ketones. These unsaturated ketones can produce long-chain coloured polyenes. Additionally, if 1,4-diketones are formed during the drying, enol tautomers can react with trace amounts of atmospheric ammonia.
This produces a substituted pyrrole, that can be converted into a coloured product by oxidation, or by condensation in the presence of formic acid. Coloured metal siccatives can also contribute to discoloration and/or yellowing.
While this can be a complex subject, if broken down into steps, it becomes much easier to understand. The plethora of reactions and changes that occur during the drying process, turn a liquid oil into a solid film. A bit of magic to be sure!
http://www.sydneywoodturners.com.au/site/articles/finishing/oils.html
There have been some threads over the last few months, that have debated the relative merits of Tung oil and Linseed oil. In order to shed a bit of light on the complex drying process of these two oils, the following is a general introduction to both oils.
Linseed oil is made from the seeds of the flax plant (Linum usitatissimum L.) Tung oil (aka wood oil, chinawood oil) is made from the seed kernels of the Tung tree (Aleurites fordii). Drying Oils can be defined as liquid vegetable oils that, (applied in thin layers to a non-absorbent substrate), will dry in the air to form a solid film.
This drying, is a result of polymerization by the action of atmospheric oxygen (autoxidation). Two common drying oils are Tung oil and Linseed Oil. The resultant film formed is typically hard, non melting and usually insoluble in organic solvents (this varies with the particular oil).
Nonconjugated oils, such as Linseed oil, are fatty oils that contain polyunsaturated fatty acids, whose double bonds are separated by at least two single bonds. Conjugated oils on the other hand, such as Tung oil, are polyunsaturated fatty acids whose double bonds are partly or fully conjugated.
The place of cultivation and its climate can alter the fatty acid spectrum of a drying oil. The high proportion of linolenic acid in nonconjugated oils (like Linseed oil), affects its drying characteristics. High concentrations of linolenic acid can result in rapid drying, yellowing and brittleness.
Conjugated oils like Tung oil, are considerably more reactive than nonconjugated oils (like Linseed oil). Conjugated double bonds favour polymerization and oxidation and dry more rapidly than nonconjugated oils. The resultant film offers a high resistance to yellowing and increased resistance to water and alkalies.
The principal drying component in Tung oil is eleostearic acid, a conjugated octadecatrienoic acid. The oleic acid contained in the fatty oils and unsaturated fatty acids plays a small part in the drying process as well. The saturated fatty acids present act only as plasticizers.
The drying of films typically progress in three overlapping steps:
1. Induction - through a process known as autocatalysis, the oxygen uptake steadily increases. Factors such as temperature, light and heavy metals/inhibitors in the oil, affect the overall uptake rate.
2. Initiation - as the film continues to take up oxygen, its mass increases. The double bonds in the film begin to rearrange and polar groups such as hydroxyl and hydroperoxy develop in the film. This leads to the association of molecules through forces such as hydrogen bonding.
3. Cross-Linking - As the number of double bonds in the film begin to diminish, larger molecules form and volatile and non-volatile carbonyl compounds are generated.
The exact chemical reactions in these steps, as well as the structure of the film-forming polymers, are not fully understood. The initial autoxidation step in nonconjugated oils (Linseed), is dehydrogenation of the unsaturated fatty acid by oxygen, which forms a radical. This starts a radical chain reaction that increases incrementally with time, leading to the formation of a hydroperoxide.
At low levels, the hydroperoxides produced during autoxidation, decompose to form free alkoxy and hydroxyl radicals. Higher levels of hydroperoxides form free radicals through boimolecular disproportionation. The resultant free radicals react in various ways to accelerate the autoxidation process.
The drying of Tung oil varies considerably from Linseed oil. Tung oil typically absorbs approximately 12% oxygen (Linseed oil absorbs approx. 16%) and quickly forms a skin on the surface. Since less oxygen is absorbed, the viscosity of the oil increases at a faster rate. Unlike the hydroperoxide formation during autoxidation in Linseed oil, Tung oil forms cyclic peroxides. (The methyl eleostearate formed has a higher molecular mass than linoleic acid esters).
The direct attack on the double bonds by oxygen forms cyclic peroxides. The resultant reaction of the peroxides with allylic methylene groups, leads to the formation of radicals. This creates a radical chain reaction, that forms polymers. The molecular mass created is less than that achieved through Linseed oil polymerization. To speed up the film formation, manufacturers add driers to the oils.
Driers are oil soluble metal salts of organic acids. When these driers are dissolved in aliphatic or aromatic hydrocarbons, they are known as siccatives. When driers are added to drying oils, they are known as Boiled Oils. In order to increase the viscosity of the Boiled Oil, air is sometimes "blown" through the oil at 60-100 degrees Centigrade.
Rags soaked with drying oils (treated with siccatives) present a significant danger of exothermic autoxidation, which could lead to spontaneous combustion. Therefore, when working with boiled oils (or other oils treated with driers or siccatives) you must pay careful attention to the safe disposal of any oil soaked rags. The rags should never be folded, crumpled or otherwise compressed, until the oil has fully dried. Proper disposal according to manufacturer's recommendations i.e. fireproof containers, should be used if possible.
The yellowing of Linseed oil is caused when conjugated unsaturated hydroperoxides are converted into conjugated unsaturated ketones. These unsaturated ketones can produce long-chain coloured polyenes. Additionally, if 1,4-diketones are formed during the drying, enol tautomers can react with trace amounts of atmospheric ammonia.
This produces a substituted pyrrole, that can be converted into a coloured product by oxidation, or by condensation in the presence of formic acid. Coloured metal siccatives can also contribute to discoloration and/or yellowing.
While this can be a complex subject, if broken down into steps, it becomes much easier to understand. The plethora of reactions and changes that occur during the drying process, turn a liquid oil into a solid film. A bit of magic to be sure!
cracked butt
Member
I know a lady who burned her house down after finishing some woodwork with BLO, the rags were piled in the corner of her garage and started the fire. I hand the rags I work with to dry before disposing of them, leaving them in a pile or closed container while wet is likely to start a fire.
I had an M1 carbine (IMA?) with a stock that wasn't smooth enough for my tastes. I believe it had a linseed oil finish. I went over the stock with some super fine sand paper, and then applied about four coats of tung oil.
Beautiful and soft.
I've used tung oil to finish a number of 6' staves and 3 and 4' sticks. It works well.
John
Beautiful and soft.
I've used tung oil to finish a number of 6' staves and 3 and 4' sticks. It works well.
John
jonnyringo
Member
I prefer Tung oil. The key is thin coats and wet sanding in the first coat. I apply about 7 to 10 very thin coats. You need to take your time, allowing plenty of drying time indoors.
Brian Dale
Member
I've done it.
No problems at all.
Markbo, as you can see from W.E.G's post, the tung oil won't lift the linseed oil; the linseed oil's already polymerized.
Be sure to dispose of the rags properly.
No problems at all.
Markbo, as you can see from W.E.G's post, the tung oil won't lift the linseed oil; the linseed oil's already polymerized.
Be sure to dispose of the rags properly.
jrfoxx
Member
I prefer tung oil too, as I like how it makes a harder coat, that seems like it would seal the wood better againg grunge and the elements compared to just using BLO.Also, I never got the nack of rubbing in the BLO like its supposed to be to get it to really look nice like most others can (I was never able to get that incredible super mirror finish in my boots in the Navy like others either, no matter what I did, even doing exactly like people told me).Apparently I'm defective.With tung oil though, I was always able to get it looking really nice, really easily.I will say that tung oil, every time I used it, did seem to take a couple days at least to dry enough to not feel at all tacky, even keeping it indoors with low humidity and around 68-70 degrees.
So, since I never got the knack of BLO, but tried it almost every time to see if I could get it to come out right, most of mine ended up being tung over BLO, and I never saw it have any negative or unusual/undesireable effect compared to ones I did later wher I used just the tung oil.
As for the combustion thing, I always assumed both were bad news on used rags, so they were burned in the BBQ whenever I was done for the day.Better safe than sorry IMHO.Getting new rags is cheap, replacing everything I own from a fire is not....
So, since I never got the knack of BLO, but tried it almost every time to see if I could get it to come out right, most of mine ended up being tung over BLO, and I never saw it have any negative or unusual/undesireable effect compared to ones I did later wher I used just the tung oil.
As for the combustion thing, I always assumed both were bad news on used rags, so they were burned in the BBQ whenever I was done for the day.Better safe than sorry IMHO.Getting new rags is cheap, replacing everything I own from a fire is not....
the naked prophet
Member
Maybe I was confused. Nevermind. Carry on.
GBExpat
Member
"Has anyone ever tried applying a coat of tung oil directly over a stock finished in linseed oil?"
I probably have ~20 stocks that I have done that way. With many USGI milsurps I first do a cleaning process with 0000 steelwool and BLO:loMS mixture (~2-3:1) and follow that with 1 or 2 TO:loMS apps.
I have found that BLO & Tung Oil play together very well.
Be aware the many/most/all? products named something like Tung Oil Finish are actually varnishes.
I probably have ~20 stocks that I have done that way. With many USGI milsurps I first do a cleaning process with 0000 steelwool and BLO:loMS mixture (~2-3:1) and follow that with 1 or 2 TO:loMS apps.
I have found that BLO & Tung Oil play together very well.
Be aware the many/most/all? products named something like Tung Oil Finish are actually varnishes.
Bulgy Handguard Finish?
Since we are on the subject of finishes I have a question. I have a couple of unfinished beechwood AK handguards that I want to finish to look like the Bulgarian ones. Does anybody know of a technique to get something like that? The Bulgarian one is shown on somebody else's finished firearm in the pic. I cannot just go out and buy the Bulgarian ones b/c I have to remain 922r compliant.
I know how to do the sanding I just need to know which finish (tung oil, BLO, etc.) to use.
Thanks for any help!
Since we are on the subject of finishes I have a question. I have a couple of unfinished beechwood AK handguards that I want to finish to look like the Bulgarian ones. Does anybody know of a technique to get something like that? The Bulgarian one is shown on somebody else's finished firearm in the pic. I cannot just go out and buy the Bulgarian ones b/c I have to remain 922r compliant.
I know how to do the sanding I just need to know which finish (tung oil, BLO, etc.) to use.
Thanks for any help!
Attachments
Keith, it may just be my eyes or the picture, but the finish on those handguards looks a little to glossy to be BLO or tung oil. Looks almost like a low-gloss or semi-gloss poly.
As I'm sure you know, the glossier the finish, the more likely it is to get dirty and crusty from hand sweat and dirt. I finished my AK handguards with tung oil to keep them as smooth as possible.
As I'm sure you know, the glossier the finish, the more likely it is to get dirty and crusty from hand sweat and dirt. I finished my AK handguards with tung oil to keep them as smooth as possible.
Brian Dale
Member
GBExpat is right. Lauer Custom Weaponry sells pure tung oil, though. They're the Dura-Coat people. You'll find pure tung oil if you scroll way down, far past the short barreled rifles and suppressed weapons, in the "CHOOSE PRODUCT" box at the bottom of the page at this link:GBExpat said:
Lauer Custom Weaponry
There are other relevant links in posts 2, 4 and 7 of this THR thread. Post #8 has a partial list of which products seemed to be oil / varnish blends and which seemed to be wiping varnishes (without oil) as of a few years ago.
pdowg881
Member
i have used Formby's Tung oil finis with excellent results. It has thinners in with the tung so you just go ahead and rub it in and let it dry. Three coats or so leaves a nice finish. I used it on a Yugo sks.
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