# pure tung oil help, is still hazy



## shatterjack (Jan 4, 2018)

Hi everyone,
I’ve been adding layers to this walnut nightstand, I think I have six coats of pure tung oil from Rockler on it, but there was one that got left on too thick and I had to rub off a bunch of semi-dried oil (that white flakey stuff), as a precaution I sanded it down with 400, a few coats in the middle I wet sanded with the white super-fine plastic sanding pads, I also tried some 0000 steel wool in there, basically just trying to get the finish to be more clear I guess (not necessarily glossy but not hazy either). There are two pictures of the piece with the tung oil wet on it and then after the coat has dried with some closeups. I’m not sure if I over-sanded it or if I need to buff it, I’m really lost at this point. I guess I can keep putting coats on, but when people talk about haziness with tung oil, it’s usually just in some spots with the rest looking pretty good, but this is basically all super matte finish in appearance. Thanks a lot for any help!


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## Steve Neul (Sep 2, 2011)

If you put water on the spot would it still look hazy? If so there is a problem there which more coats isn't going to help. The cloudiness would be some foreign substance suspended in the finish. If the cloudiness goes away when wet with water then there is some roughness in the finish which is fixable. By sanding and applying more coats it would clear up. 

Stop using steel wool between the coats of any finish. Steel wool is dirty and can add some problems like you are experiencing. Only use steel wool to buff a finished coat.


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## shatterjack (Jan 4, 2018)

Hi Steve,

Thanks for the reply, yes it looks great when wet with a little water or with a wet coat of tung oil. For sanding, would you recommend dry sanding, wet sanding with the wet coat of tung oil, or both? I have some 400 and 600 "waterproof" sandpaper as well as the superfine white plastic scrubby pads from Rockler, they didn't know what the corresponding grit was for those but it's pretty high. Thanks a lot


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## Steve Neul (Sep 2, 2011)

shatterjack said:


> Hi Steve,
> 
> Thanks for the reply, yes it looks great when wet with a little water or with a wet coat of tung oil. For sanding, would you recommend dry sanding, wet sanding with the wet coat of tung oil, or both? I have some 400 and 600 "waterproof" sandpaper as well as the superfine white plastic scrubby pads from Rockler, they didn't know what the corresponding grit was for those but it's pretty high. Thanks a lot


What is happening there causing the problem is the wood has some roughness and now needs to smooth with the finish. I would use 180 or 220 grit paper on just the spot and coat just the spot. Just be careful not to sand through the finish. Then when you get it worked out use the 400 grit paper on the whole thing and put the last coat.


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## Quickstep (Apr 10, 2012)

It looks to me that the area your working on is absorbing more oil and not getting as glossy as the surrounding area. It may also be a different color because of what's going on around that knot. Additional coats should do the trick. Also, be sure you let each coat dry before adding the next; otherwise, you're just re-dissolving the previous coat.


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## shatterjack (Jan 4, 2018)

Thanks you guys, I sanded it with 220, wiped it down with denautured alcohol and added another coat, previously I was doing a new one every 24 hours, but I guess this time I'll wait two days between coats. You think I should 220 sand between each coat? Or maybe 400? Sorry for the specificity, it seems like you can go too high or not enough with the grit...thanks!


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## 35015 (Nov 24, 2012)

Hi Shatterjack,

Can't commend you enough on the choice to go with an honest natural finish. I still contend there is nothing better, easier, longer lasting or easiest to maintain/refinish than the methods that have been with us for millenia...Good for you.

Observations:

Figured wood can have natural oils and resins all there own to challenge us in certain areas...especially some species like nut trees, and often around knots. I would also offer that "pure tung oil" often isn't pure at all. It has been adulterated with all manner of petroleum byproduct. This is more common than you would think. I go for "food grade" and/or sources that make an effort to only sell traditional natural grades of these many heritage finishes...

I like planning methods over sanding. It is both traditional and leaves a superior finish on the wood, just like "riven wood" behaves different than sawn. When I do sand (and I do it a fair amount on some projects) you can not go too high in grit. I have taken raw green Norway Spruce (as an example) fresh off the mill, and scrub planned it for detailing the surface and sanded it in succession down to 1000 grit. You could read a credit card on the surface as the natural oils, resins and moisture reacted to the sanding and then polishing effect of the higher grits...It looked as if it had been buff waxed, which we did do to the timber before placement in a frame. Mill to frame...less than 8 weeks. Gloss finish persisted through rain and exposure of a solid several weeks, and then slowly took on an aged look that couldn't be produced with other methods as we exposed the timber frame to natural bleaching and oxidation.

Depending on your goals, sand to whatever fine abrasive you wish to...Our minimum for "fine sanding" is at least 320 grit to 600 grit...Otherwise just a well planed surface can also take a fine polish of wax and oil...

Good luck...


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## Steve Neul (Sep 2, 2011)

shatterjack said:


> Thanks you guys, I sanded it with 220, wiped it down with denautured alcohol and added another coat, previously I was doing a new one every 24 hours, but I guess this time I'll wait two days between coats. You think I should 220 sand between each coat? Or maybe 400? Sorry for the specificity, it seems like you can go too high or not enough with the grit...thanks!


I don't think I would be using denatured alcohol to clean between coats. A finish isn't completely dry for a month and alcohol is an awful strong chemical to be used on even a dried finish. You would be better off using naphtha if you are going to use a solvent. Myself, I just use a soft brush and compressed air.


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## 35015 (Nov 24, 2012)

Steve Neul said:


> I don't think I would be using denatured alcohol to clean between coats. A finish isn't completely dry for a month and alcohol is an awful strong chemical to be used on even a dried finish. You would be better off using naphtha if you are going to use a solvent. Myself, I just use a soft brush and compressed air.


If I may perhaps challenge that perspective a bit?

Naphtha, as it is today, is a petroleum byproduct and well outside the realm of what was available, and not all applicable traditionally (nor something I would recommend) for cleaning a wood taking a natural oil finish later, such as tung. 

Naphtha, by simple term is exceedingly generic, and has many acient and traditional meanings. From a traditional finishing modalities perspective, I agree, traditional elements going by the term "naphtha" could have there place. Nevertheless, these where actually something like Palmitic acid (originally called naphtha) and would indeed have had an applicable use in some methods.

Modern grain based ethanol (which have additives to render them noxious to drink) are no less harsh chemically (I would suggest much less so) than petroleum based naphtha, which again I would not recommend at all for a cleaning agent prior to a natural/traditional finish. 

Grain alcohols, heated water and a lie soap/fat paste, pine oils, citrus zest (aka rind pulp with its citrus oils or the extracts themselves), and/or turpentine of various forms being other common elements of traditional cleaning cutting agents. Even "lime paste" and fat, just lime paste alone, Horse Tail, Rush, and other mineral and/or botanicals too where commonly employed in various modalities within traditionally finishes.

What hasn't been offered as a solution yet, and a very common traditional one that comes in too many forms to list here, is a "wood poultice ." 

For set in stains, blemishes, and other related challenges both innate or foreign to the wood a poultice of some form is a viable option.

Typically a poultice forms some type of "drawing agent" be it for flesh of body or a piece of wood. It can constitute any manner of anodyne absorbent material. DE (diatomaceous earth), buckwheat flour, cornstarch, clay, etc. are all common pollutes bases. These can be mixed with a myriad of traditional solvents already mentioned to form a paste. Water itself is a rather strong solvent working in concert with other additives. 

In the case of the black walnut of this post, I am not certain that more than some grain alcohol or citrus solvent is warranted however, and then finishing as intended with tung oil...


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## Steve Neul (Sep 2, 2011)

Jay C. White Cloud said:


> If I may perhaps challenge that perspective a bit?
> 
> Naphtha, as it is today, is a petroleum byproduct and well outside the realm of what was available, and not all applicable traditionally (nor something I would recommend) for cleaning a wood taking a natural oil finish later, such as tung.
> 
> ...


I don't like the concept of using any solvent to clean between coats however some of these guys think they need to. In my experience denatured alcohol can cloud or lift a finish especially one that isn't cured yet however naphtha won't bother any finish unless it isn't dry to touch yet. Some of these guys will use mineral spirits to clean with but it doesn't dry very well and will get into the next coat if someone doesn't buff it well with a clean dry cloth. Naphtha will at least dry.


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## 35015 (Nov 24, 2012)

Steve Neul said:


> I don't like the concept of using any solvent to clean between coats however some of these guys think they need to. In my experience denatured alcohol can cloud or lift a finish especially one that isn't cured yet however naphtha won't bother any finish unless it isn't dry to touch yet. Some of these guys will use mineral spirits to clean with but it doesn't dry very well and will get into the next coat if someone doesn't buff it well with a clean dry cloth. Naphtha will at least dry.


I understand part of this logic, and it is sound when considering a specific method...

Thinning and blending techniques between coats of a finish (traditional or otherwise) is a technique some folks like and some (many?) have great success with it...so I can respect an individual view point on it...

Nevertheless, it isn't a singularity one method vs another...as cleaning between coats or "softening" methods do and can work or folks wouldn't use them...

I don't (or extremely seldom) employ any modern finishing method...especially any from petroleum byproduct...I see no need to, but that is a style choice, not necessarily a "right or wrong," and I understand that...

Chemically alcohols and petroleum based naphtha both effect uncured polymeric reactions...that is just plan chemistry, and not something that can really be discussed/debated...It just is what it is...Natural finishes can be more sensitive but can be augmented/repaired easier than others, especially modern ones...


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## shatterjack (Jan 4, 2018)

thanks you guys, I think I was using the solvent since when I went to sand the finish there would be some gumming up of the sandpaper and I was worried about a film or something getting left on the surface, but I guess I'll skip it and just continue to rub the surface clean with a dry clean rag, I left the last coat to dry for more than two days and rubbed it really well to get any excess oil off, it seemed really dry but yet it will still gum up a 400 grit piece of sandpaper even with a very light sanding. The humidity is low and the temperature is 60s-70s throughout the day, I have good airflow through the drying space, but maybe it still needs more than two days to dry per coat? (the first time through it was about one day per coat) or maybe drop back to the 220 in between coats? I just put on the second coat, I'll let you know how it goes. Thanks again


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## Steve Neul (Sep 2, 2011)

shatterjack said:


> thanks you guys, I think I was using the solvent since when I went to sand the finish there would be some gumming up of the sandpaper and I was worried about a film or something getting left on the surface, but I guess I'll skip it and just continue to rub the surface clean with a dry clean rag, I left the last coat to dry for more than two days and rubbed it really well to get any excess oil off, it seemed really dry but yet it will still gum up a 400 grit piece of sandpaper even with a very light sanding. The humidity is low and the temperature is 60s-70s throughout the day, I have good airflow through the drying space, but maybe it still needs more than two days to dry per coat? (the first time through it was about one day per coat) or maybe drop back to the 220 in between coats? I just put on the second coat, I'll let you know how it goes. Thanks again


OK, if the finish is gummy you need to stop and let the finish dry. Working tung oil is very different than working any other finish. It may be the slowest drying finish there is. Since it's cool where you are it may take more than a week for a coat to dry. The best way to tell if the coat is ready to sand and recoat is to briskly rub the finish with a clean dry cloth and see if any of the tung oil smell rubs off on the rag. When there is no smell it's ready.


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