Posting here to get maximum exposure. To those of you who have used Japan dryer in Tung Oil, how much do you add to a pint of the oil? Zero instructions on the can. Thanks.
forestgirl — you can take the girl out of the forest, but you can’t take the forest out of the girl 😉
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Well, she says, talking to herself. I got info (finally), from the best sources -- Michael Dresdner and Jeff Jewitt. Japan dryer usually doesn't have the right compounds in it for tung oil. A cobalt dryer is required. Japan dryer is used for linseed oil. So, any future references to tung oil w/JD are bogus.
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I guess I'm not ready to take on faith Jeff and Mike's advisory about Japan driers and Tung oil, as it seems to run counter to my organic chemistry background. Since Tung oil is more reactive than seed oil, I'd expect a drier would promote curing more in tung than seed oil. I think highly of Mike and Jeff's work, but I have no gauge on their organic chem knowledge.
I think I'll devise an experiment and see for myself, unless someone can point me to literature that covers this already (with experimental evidence). One thing I learned at the old UW was don't believe everything you read or what the experts say. Mistakes and mistaken ideas abound in all walks of life.Recommending the use of "Hide Signatures" option under "My Preferences" since 2005
They're not saying a dryer doesn't work, just that it needs to be a "cobalt dryer" and not the other (salts? elements? whatever) things. You can tell I'm still in the dark here. Chem was not my forte.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
What they are saying is that the metals in some commercially available driers do not contain cobalt, but other metals, and that cobalt has the catalyzing capability that other salts don't.
My scepticism comes from tung oil being more reactive, and I would think more easily catalyzed, and therefore wouldn't need a "higher strength" catalyst. It's really a lot more simpler than that, you just have to concern yourself with electron delocalization along the conjugated bonds...
Again, Jeff and Mike might be right, but unfortunately I know just enough to get confused. I'd appreciate a lit citation to see why they are right, and if they are right. I take nothing as gospel...
Recommending the use of "Hide Signatures" option under "My Preferences" since 2005
Hi Mr. Fish, I'm going to persue this, though it may take a few days. So far I'm seeing references to both cobalt and manganese in relation to tung oil, with the cobalt being present at a higher percentage. I'm determined to get to The Truth (after all, The truth is out there.... X ) I'll see if I can find some true "lit" on it. Thanks for your interest.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I've used this product (Sutherland Welles "Millie's") with success and without the addition of a dryer:
MILLIE’Sâ„¢ ALL PURPOSE PENETRATING TUNG OIL (PRINTABLE PDF)
Millie’sâ„¢ All Purpose Penetrating Tung Oil was developed as a foolproof, easy-to-use, low-toxic, earth-friendly Polymerized Tung Oil. It is safe to use on all types of porous surfaces. Unfinished wood surfaces such as salad bowls, butcher blocks, cutting boards, furniture, floors, wooden garden tool handles (even coating the metal for winter storage will inhibit rust), timber frames and beams. It is the perfect, easily renewed, sealing agent for paint, brick, concrete, porous slate, terra cotta tile and milk paint.
Millie’sâ„¢ is totally botanical, made from all biodegradable, all natural and plant-derived ingredients ! It is formulated with our Pure Polymerized Tung Oil - a vegetable oil, Di-citrusolâ„¢- our citrus-derived solvent and beeswax. There are no petroleum distillates or driers added to Millie’s formulation.
Polymerization and Formulation
As Tung Oil dries and cures, the molecules join together in a tight complex formation. This process is the secret to Tung Oil’s effectiveness as a finish. The cross linking of the oil’s molecules makes the surface waterproof and impervious to many chemicals. The bonding also gives flexibility to the surface, making it capable of withstanding wear and tear.
Sutherland Welles Ltd.â uses a process, polymerization, to intensify Tung Oil’s natural cross-bonding tendency. Polymerization utilizes a cooking process that changes the molecular structure of the oil and further improves the natural cross-bonding reaction of raw Tung Oil.
Many other manufacturers of Polymerized Tung Oil will claim that they polymerize their oil, but their “cook” is not as extensive as ours and requires formulation which includes additives such as varnishes and urethanes to improve the hardness, durability, and lustre of the finish. This adds to the toxicity of the finish and inhibits the penetration of the oil into the wood fibers as well as slowing the drying and curing time.
The polymerization process used by Sutherland Welles Ltd.â is very sophisticated and “cooks” the pure, raw Tung Oil to its “maximum thermal threshold”. Controlling the “cooking” and the “cooling” is an expensive process that, at its perfect point, produces a finishing oil with maximum durability and a gorgeous sheen. If the process isn’t well controlled, the oil solidifies to the consistency of an erasure and the entire batch is lost. The intricacy and therefore expense of the process is what leads most companies to formulate with modifiers. They believe they can achieve the same results with a cheaper process and formulation. In time, the varnishes and urethanes discolor and deteriorate and with it the finish.
Polymerization increases the viscosity of the Tung Oil making it difficult to work and reduces penetration. The Polymerized Tung Oil must be formulated with solvents to thin the oil to maximize its workability and penetration. The beeswax adds protection to the surface and helps create the beautiful low sheen of a hand-rubbed finish.
There are no driers in this finish, therefore there is no set-up time or cure time required between applications. The surface is treated as a sponge. Coat after coat of Millie’s is applied until the surface is saturated as evidenced by the gummy accumulation of the oil on the surface. No wiping or rubbing is required until the final coat.
Application of Millie’s on wood:
The best results with Millie’sâ„¢ are achieved on new, unfinished, wood surfaces. This allows maximum saturation to occur which provides maximum protection. The final sanding on the new wood surfaces should be no higher than 180/200 grit. For turnings, start applying Millie’s at around 120 grit and then polish off to final sanding and apply a thin, hand wiped coat as a topcoat. Millie’s can be applied with a clean natural bristle brush, foam brushes are fine or for floors, use a short-napped lamb’s wool applicator. Warming Millie’s by setting your pail full of Millie’s into another pail of hot water will increase penetration. Simply flood out a coat so the entire surface is wet with Millie’s and allow that coat to be absorbed. Most wood species will absorb three applications. You may re-coat as soon as the previous coat is absorbed, there is no need to wait for the surface to dry or cure.
You will know when the wood is saturated as the absorption time is longer and the surface feels gummy as Millie’s Oil is lying on the top of the wood. The final step is to apply one last coat of Millie’s in the same manner, using less oil but enough to cover the entire surface. Allow 10-15 minutes (or less) for this freshly applied coat to saturate and dissolve the Millie’s that has gummed up on the surface. Using a #0 or #00 steel wool pad, rub the wet surface vigorously using a circular motion. Buffing removes the burr of the wood and builds the sheen on the surface. Replace the steel wool pad when it becomes saturated with Millie’s. The final wipe should be done with a clean soft rag to pick up any excess Millie’s not absorbed by the steel wool . Wipe in the direction of the grain. After the final wipe, the wood should be completely dry to the touch with the Millie’s completely and thoroughly removed from all surfaces. Allow approximately 72 hours for the surface to cure before using.
Millie’s on wood floors:
Apply Millie’s per the above instructions. After you have reached saturation (surface is gummy), apply the last coat of Millie’s and allow 10-15 minutes for Millie’s to dissolve the oil that saturated to the surface. You need to work in small sections as the surface becomes very slippery. Using a buffing machine with #1 steel wool pads, buff in Millie’s, changing the steel wool pads when they become saturated. If using a buffing machine, simply use a synthetic white polishing pad for your final buff on the entire surface or a clean terry cloth towel under the buffing machine. Buff/wipe in the direction of the grain. If wiping by hand, the final wipe should be done with a clean soft rag to pick up any excess Millie’s not absorbed by the steel wool. After the final wipe/buff, the wood should be completely dry to the touch with the Millie’s completely and thoroughly removed from all surfaces. Allow approximately 72 hours for the surface to cure before using.
Millie’s on other porous surfaces:
Surfaces such as brick, concrete, cork, porous slate, terra cotta tile and milk paint should be as clean as possible before applying Millie’s. Apply with a brush or rag, do not wipe. After each coat is absorbed, reapply until the surface becomes saturated. The saturated surface will feel gummy. Reapply another coat of Millie’s wait 5-10 min. for it to dissolve the gummy coat and then buff completely off with cheesecloth or a clean soft rag. Allow the surface to cure 72 hours before use. If the surface appears too shiny after curing, buff with #0000 steel wool or a fine grade synthetic Scotch pad.
Maintaining a Millie’sâ„¢ finish surface
Periodic coating with Millie’sâ„¢ will protect as well as clean the surface. The frequency of maintenance is a function of how much the surfaces are used. Apply when the surface looks dull or feels dry. More use will require a more frequent re-coating. If the surface has been maintained regularly, apply only one coat and buff into the surface immediately. Wipe thoroughly dry. Allow to cure 6-8 hours before using the surface. If the surface hasn’t been maintained regularly, you may need 1-2 coats. Test the surface by applying a thin coat and observe to see if the surface absorbs the finish quickly. If it does, apply a coat and wait for it to absorb. When completely absorbed, apply another coat and buff the surface dry with a white polishing pad or terry cloth towel beneath the buffing machine or buff by hand for small surfaces.
Coverage: For unfinished wood: Quart: First coat: 75-150 sq.ft. Second coat: 150-200 sq.ft. Gallon: First coat: 300-600 sq.ft. Second coat: 600-800 sq.ft. Successive coats require less oil and are dependent on the type of surface. Most wood surfaces finished according to the directions stated above, will take 3-4 coats to achieve total saturation.
For other porous surfaces: Such as concrete, cork, slate, brick, terra cotta tile, saturation may be achieved in one coat with coverage averaging 200-250 sq.ft./quart or 800-1000sq.ft./gallon.
"Polymerization increases the viscosity of the Tung Oil making it difficult to work and reduces penetration. The Polymerized Tung Oil must be formulated with solvents to thin the oil to maximize its workability and penetration." Wonder what kind of solvent they use.... Oh, wait I see: "Di-citrusolâ„¢- our citrus-derived solvent."
I thought about ordering polymerized tung oil, but opted for the raw stuff at the last minute.
When this thread is totally exhausted, and we've found our chemical treatise on T.O. and dryers, I'm going to harvest the best of it and re-print it in "The Ultimate Tung Oil Thread."
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Edited 2/20/2006 11:57 am by forestgirl
I stumbled across one of the pages that BossCrunk quoted above and felt that the original should be cited. It is here:http://www.sydneywoodturners.com.au/site/articles/finishing/oils.htmlforestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Wouldn't it be easier to find a tung oil that already has the proper dryers in it, "factory installed"? I haven't gone looking for pretreated tung oil but I'd be very surprised if it weren't available.
John W.
"Wouldn't it be easier to find a tung oil that already has the proper dryers in it." I tried, I tried! :-( Ace Hardware here on the island used to carry some, can't remember what brand. I swear to the heavens above, it's so hard to get any kind of decent finishing supplies at the stores these days!
The only tung oil (100%) I could find was at Woodcraft, and that took a ferry ride ($17) and 3 hours of my time to pick it up, after looking at Ace, Lumbermen's, Lowe's, HD and the local Jet/Delta dealer's place. Turns out, there is some now at a local fru-fru designer paint store here. forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
One teaspoon per pint for linseed oil.
Edited 2/17/2006 7:07 am ET by BossCrunk
Now that I have a pint of Japan dryer, I'll have to do the linseed oil thing I guess. What a waste of time all that was. You can bet every time I see a post re: tung oil with JD, I'm going to pounce. Total myth.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
I've personally never used Japan drier with tung oil. That said, I've also had more than one quibble with Messrs. Flexner, Jewitt, et al. Not everything they say is the gospel.
You might consider contacting the manufacturer of the particular tung oil formulation you've bought and get the word from the horse's mouth. I may be wrong, but I don't think any of the popular finishing experts are formally trained as chemists. Finishing manufacturers will have organic chemists galore in their employ.
If you need a linseed oil forumulation with dryers already added then I'd simply use Watco.
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.
Edited 2/18/2006 8:39 am ET by BossCrunk
Found on the 'net:
Then there is tung oil. Tung oil itself is one of the finest finishes there is, but you need to watch closely to be sure of what you're getting when you buy tung oil. For starters, there is 100% tung oil, but be sure to read the label and ingredients, because some manufacturers believe that the tung oil they use is 100% tung oil, but they add solvents to make the tung oil more workable, so you're getting 100% tung oil with solvents. Straight 100% tung oil is difficult to work with, because it's thick and you need to apply very thin coats to have it dry and cure properly. The more honest manufacturers will call their product something like Tung Oil Finish, which is generally tung oil cut with solvents to make it more workable and driers to make it dry quicker. Some manufacturers will add UV protection too. It's best to stay away from any urethane ingredients.Tung oil doesn't need any UV protection for itself and if you stain the wood with pigmented oil stain that will pretty much take care of the UV protection for the wood. Teak is pretty tough stuff and resists deterioration from the UV rays anyway. Most woods will look better if they're stained with a neutral color stain anyway to even out the color.Then there is polymerized tung oil. You may see different tung oil finishes with different amounts of gloss. Generally to get the different gloss levels different amounts of polymerized tung oil are used compared to the solvents. Polymerized tung oil should have some UV protection for itself as it isn't as hardy as 100% tung oil, even cut with solvents, but the UV protection isn't a must, it just means that you may have to apply a new coat of tung oil a little bit sooner than you would with the UV protection. Non-polymerized tung oil has more of a sheen than a shine.Polymerization is a natural process, but polymerized tung oil is 100% tung oil given a little help by heating to get part of the polymerizing done quickly, so the end product will dry quicker and will have a higher shine, but will usually have to be cut more with solvents, because the straight polymerized tung oil is kind of gooey and almost impossible to work with.The smart people who know such things say that polymerization is the combination of monomers to make a polymer and a monomer is a molecule that can combine with others to make a polymer. The teak oil molecules are very small, so they can get into the wood easily and the natural polymerization means that each successive coat of tung oil will bind itself to the previous one to make a thicker protective coat.Tung oil will generally take 24 to 36 hours to dry, but a little japan drier can be added to speed up the drying process, but too much will cause the tung oil to be less durable.If you clean the tung oil finished wood every few months and apply another thin coat of tung oil it should last indefinitely and always look new.In a nutshell, I would recommend either one or the other, but I hope the information will help you to make your decision.There is a good product called Chinawood Deck Oil that's designed for use on decks, but is good on anything. It's 33% tung oil with solvents. You can see a little more about it in a PDF file at Chinawood oil
"The teak oil molecules are very small, so they can get into the wood easily and the natural polymerization means that each successive coat of tung oil will bind itself to the previous one to make a thicker protective coat." Not sure what this was supposed to mean (exactly). According to Mr. White over in the paid forum, "Teak Oil" is either tung- or linseed-oil based with additive to make it more weather-resistant. I deduce that the name "Teak Oil" comes from it originally being used on boats and such.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
F.G.,
I think the teak oil reference is a typo, the second part of the sentence goes back to talking about tung oil, and there is no other reference to teak oil anywhere on the page.
John W.
Edited 2/18/2006 11:56 am ET by JohnWW
Sutherland Welles Tung Oil finishes:
http://www.sutherlandwelles.com/finishin.htm
Thanks, BC. I ran across that site somewhere in my wanderings, but did not see that particular page. Re: the beginning of paragraph 4: "If bad things are going to happen finishing with Polymerized Tung Oil this is where 99.999% of disasters are created. Drying and curing are a function of the temperature and humidity in the finishing area..." it made me smile. This cold spell we're having, combined with my over-active pellet stove, has brought the RH in the shop down to about 18% -- unprecedented!!! And the temp's about 62° so it's right in the range.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
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