How to make wood pop / Accentuate grain and Chatoyance with Water-Borne Finish

[Alan Lightstone]

I personally use BLO followed by de-waxed shellac for figure accentuation. That's all followed by several coats of EM6000. For certain woods, such as tiger maple, I'll use dye first to darken the more porous wood, sand it back to further accentuate (repeating if necessary) and then do the oil, shellac and top coat to finish it off, as it were.

I've thought of trying BLO, but do worry about the spontaneous combustion. I know all the precautions necessary, etc..., Jim, but it still gets my attention enough that I haven't tried it.

That regimen you use (with either Tung Oil or Waterlox substituted for the BLO) is what I seem to be gravitating towards. Do you have any issues with it? Shortcomings, etc.

[Prashun Patel]

The spontaneous combustion concerns are IMHO easy to alleviate: 1) Don't flood the oil on; Pour a dab onto a shop towel, and rub it in. Repeat until the whole piece has been wiped down. 2) spread your towel out to dry.

You only need a little bit of oil to achieve the color and accentuation. If you flood it on, you're just increasing your drying time, wasting product, and giving yrself wetter rags that take longer to dry.

[Sam Murdoch]

To add to the discussion I offer this WoodWeb link on the subject http://www.woodweb.com/knowledge_bas...ng_Cherry.html

The Paul Snyder comment is pertinent.

[sheldon pettit]

Though the ester gum in waterlox does have a good refractive index, [1.4670-1.4710] it still is not as good as that of tung oil [1.49-1.52] but not only is a good refractive index necessary, but a good understanding of why figured woods respond to the refractions. That is to lengthy to discuss here on a forum, but well worth investigating and knowing when your trying to obtain the best results. For the casual observer, any coating that can produce a good match in R/Index's, will give the desired results wanted. For this i still recommend tung over waterlox or any other, better to use an oil by itself then overcoat with something that will give proper depth and clarity, this really rules out any water emulsions such as 6000. It has to be something with pure clarity that doesn't redirect the angle of viewing, in other-words a solvent based material.

[Jeff Hamilton Jr.]

Sheldon, you seem extremely knowledgeable and I (and no doubt others) truly appreciate your thoughts.

I've got some dewaxed shellac flakes dying to be used and wondering where a good source of tung oil can be found. This site: http://www.realmilkpaint.com/oil.html says there's is the best ...

Any suggestions?

How many coats of Tung are necessary? 1, 2, more?

Fun topic. Thanks for the opportunity to learn!

[Scott Holmes]

So they are saying that their 100% pure tung oil is better than someone else's 100% pure tung oil...
Makes me think... "Hmmmm" ....marketing hype.

As for it providing (as they say on their site)

"...but will penetrate deeply into the wood to enhance character and water resistance while creating a great wood finish."

Yes, it will penetrate deeply into the wood to enhance character, (this is pretty much all it will actually do) it will only very very slightly improve water resistance and it is NOT a good finish by itself.

I know Sheldon says it's better for popping the grain than boiled linseed oil (better refractive number) but in side by side tests I see very little difference. Tung oil doesn't darken as much over time as BLO; so, that may be a plus, may be a minus, depending on what you want to achieve.

[sheldon pettit]

Sheldon, you seem extremely knowledgeable and I (and no doubt others) truly appreciate your thoughts.

I've got some dewaxed shellac flakes dying to be used and wondering where a good source of tung oil can be found. This site: http://www.realmilkpaint.com/oil.html says there's is the best ...

Any suggestions?

How many coats of Tung are necessary? 1, 2, more?

Fun topic. Thanks for the opportunity to learn!

Jeff i'm sure most of the "pure" tung oils out there are sufficient for finishing purposes, i hate to degrade any ones offered unless i was to use them myself and test. The best i have used are from "Alnor" the leading manufacturer or distributor of all industrial oils. But unfortunately they do not sell to the public at large, though you may contact them and see for certain ok? If so, purchase the most highly refined one they have, something with the highest iodine number and unsaturation ok? if they do sell to the public, get back with that so others will know also ok? Also no matter what, keep in mind that as a first coat application you only need 1 coat, not multiples ok, let it do it's thing and then over coat with varnish/waterlox/ or whatever else but water dispersed top coats. Oh, as reguards to Alnor, be prepared to buy more than just a pint or quart, they do not sell in small quantities last i know of ok? Thing is i have not purchased from them for some time now so i don't really know where thier at on these things, good luck.

[sheldon pettit]

So they are saying that their 100% pure tung oil is better than someone else's 100% pure tung oil...
Makes me think... "Hmmmm" ....marketing hype.

As for it providing (as they say on their site)

"...but will penetrate deeply into the wood to enhance character and water resistance while creating a great wood finish."

Yes, it will penetrate deeply into the wood to enhance character, (this is pretty much all it will actually do) it will only very very slightly improve water resistance and it is NOT a good finish by itself.

I know Sheldon says it's better for popping the grain than boiled linseed oil (better refractive number) but in side by side tests I see very little difference. Tung oil doesn't darken as much over time as BLO; so, that may be a plus, may be a minus, depending on what you want to achieve.

"hype", lol, yes and that's why i don't pick or choose unless i'm needing certain other qualities such as higher/lower hydro peroxide content or unsaturation for increased hydroxyls for combining with other resins or chemicals.

As to visual response to refraction indexes, when their as close as say BLO and pure tung, you correct, that is normally measured with a refractometer, just like color is judged with a color spectrophotometer because we can't see many colors when they vary minutely, take for example a very light tinted latex paint - how many can look at it and say when the colors vary in appearance by as little as 1/128 of an ounce or less how close two close colors are? that's why i had problems trying to convince anyone of the differences in optical appearances with oils, lol. It can be seen but in your case and others here it does appear to be little difference, but again as you say - tung also does not continue to darken as Lo does. To me that's a good point, lol.

Lastly, tung is not used as it once was long ago, there was none of this let penetrate for awhile and then remove all the excess, this is also true of linseed oil to a same extent also. cold pressed oil's were used, there was no heating to thermal temps. and removal of mucilage [break] or any fats etc. It was applied as pressed and basic filtering was done and only lower heat levels if any. A thin coat was left on to build the finish and with using that type of oil could give incredible protection such as on ship hulls with the ancient Chinese. a sample of such use follows:


Oil Polish.—One quart of cold-drawn linseed-oil to be simmered (not boiled) for ten minutes, and strained through flannel; then add one-eighth part of spirits of turpentine: to be applied daily with soft linen rags, and rubbed off lightly; each time the oil is applied the surface should be previously washed with cold water, so as to remove any dirt or dust. This method of polishing is particularly useful for dining-table tops; it will in about six weeks produce a polish so durable as to resist boiling water or hot dishes, and be like a mirror for brilliancy.
Richard Bitmead, 1910

Six weeks - 42 coats, quite a build huh? who'd a thunk? lol.



With this it is shown that such can be and was accomplished, the need is to not use processed oils, just as it holds true not to use processed shellac for best results.

Ok, that's my 1 Penny's worth, I'll save the other for later, lol.

[Sam Murdoch]

Ay yi yi you guys Refractive index indeed... Interesting reading but you are leaving me in the dust - my problem not yours. I'd be proud to develop such a mirrored finish but alas none of my clients would be willing to pay for it and if I produced a finish like that for my house it would clash with the 80s decor .
Oh well...

[Alan Lightstone]

Though the ester gum in waterlox does have a good refractive index, [1.4670-1.4710] it still is not as good as that of tung oil [1.49-1.52] but not only is a good refractive index necessary, but a good understanding of why figured woods respond to the refractions. That is to lengthy to discuss here on a forum, but well worth investigating and knowing when your trying to obtain the best results. For the casual observer, any coating that can produce a good match in R/Index's, will give the desired results wanted. For this i still recommend tung over waterlox or any other, better to use an oil by itself then overcoat with something that will give proper depth and clarity, this really rules out any water emulsions such as 6000. It has to be something with pure clarity that doesn't redirect the angle of viewing, in other-words a solvent based material.

OK. Sheldon. I'll bite. You're testing my MIT and Harvard education, but what the heck, that's what it's for. Still hurting my brain.

What is the issue with refractive index in regards to water emulsions such as EM6000 that rules them out in your opinion?

[Alan Lightstone]

To add to the discussion I offer this WoodWeb link on the subject http://www.woodweb.com/knowledge_bas...ng_Cherry.html

The Paul Snyder comment is pertinent.

I agree, and I'm heading in that direction. My test samples seem to need 2 coats of Waterlox, though. The tung oil sample is looking good too.

I'm spraying shellac in between the Waterlox or Tung oil and EM 6000 for compatibility, though. Not 100% sure it's necessary (probably isn't if allowed to perfectly cure), but it sure makes the process quicker.

I'll post some pictures later in the week.

[sheldon pettit]

OK. Sheldon. I'll bite. You're testing my MIT and Harvard education, but what the heck, that's what it's for. Still hurting my brain.

What is the issue with refractive index in regards to water emulsions such as EM6000 that rules them out in your opinion?

Sorry Alan, just saw this post now.

Nitrocellulose lacquers are perfect solutions, which means the coating is completely
soluble in the vehicle (or the solvents). Water-based wood finishes are at best
dispersions, but mostly emulsions.

In a dried nitrocellulose finish for example, the light passes through the finish - all the way to the
wood grain or stained surface's at 90-degree angle, or straight down. With a water-based [emulsion] finish, the
light reflects at a 60-degree angle and doesn't reach the wood grain or stain. Fixing this
difference is possible, but no formulator wants to make that investment while
nitrocellulose lacquers or other solvent based finishes are still in existence.
Or at least that was the case when i was still active. since i have been out of it for awhile i will concede
to anyone who has updated knowledge on the subject.


From what I've read of the crytalac's line of coatings, they appear to be as the name implies "crystal clear"
but being crystal clear does not make them any less of an emulsion coating,
though if the latest most advanced resins over the last several months are being used,
it may have significantly reduced what I'm talking of, this i don't know do you?

Anyway, to test what I'm talking of you can easily buy a pane of window glass and coat part of it with the
6000, let dry good and then place it on a wood surface and view the difference between the 6000 and the crystal clear glass
as to appearances overall. If there are no differences such as equal or better clarity/depth/figure enhancement/shimmer/ etc., that would prove me wrong.
For proper evaluation as i spoke of before it would also help to apply a coat of some type of oil,
so that you do-not have the air to glass to air interface to deal with but one that is surface to surface ok?

Another thing that should be seen is when viewing items through the coated glass vs. just the glass, such a looking at a tree or car etc., is that if what I'm saying is true, then the appearances should also differ, the glass giving more distinct visual affect than the coated side. With these suggestions you should be better able to understand why it's better to for go the emulsions until such time as the problems they have are taken care of ok?

Get back with your results!!

[Alan Lightstone]

Interesting, Sheldon. Thanks.

Now if I could just find a piece of glass to do another experiment. Of course, adding the oil coat it would have to be thick enough so that it fully coats the underside of the glass and the surface of the wood, which would increase its depth dramatically compared to the depth of a true oil coating. Would that distort the results dramatically?

One thing I don't understand about your above explanation. NC lacquer is a perfect solution as you say. But how does its properties change when the solvent evaporates? In the same vein, water-borne finishes are emulsions, but after the water evaporates how do the properties change (certainly they appear to get more clear) as they are also no longer emulsions but are a hardened finish.

I guess to distill my question - How are the properties of the finishes in their liquid state relevant to the properties of the finish once it solidifies? Enquiring minds want to know...

[Alan Lightstone]

Also, the Tung Oil I used was from a bottle of Woodcraft Tung Oil I purchased a few months ago when they were having a clearance. Any comments as to the quality of their Tung Oil? Is it polymerized?

[sheldon pettit]

Interesting, Sheldon. Thanks.

Now if I could just find a piece of glass to do another experiment. Of course, adding the oil coat it would have to be thick enough so that it fully coats the underside of the glass and the surface of the wood, which would increase its depth dramatically compared to the depth of a true oil coating. Would that distort the results dramatically?

One thing I don't understand about your above explanation. NC lacquer is a perfect solution as you say. But how does its properties change when the solvent evaporates? In the same vein, water-borne finishes are emulsions, but after the water evaporates how do the properties change (certainly they appear to get more clear) as they are also no longer emulsions but are a hardened finish.

I guess to distill my question - How are the properties of the finishes in their liquid state relevant to the properties of the finish once it solidifies? Enquiring minds want to know...

As to your first question, the oil will neither add or take away in the sense that both sides of the glass will be under the same influences, the only difference will be in the properties of the coated side and whatever visual phenomena it may have to the glass side in comparison. what were trying to determine is how much affect the coated side has on distinction of image, depth, clarity, figure enhancement or lack thereof, etc.. Those are all things which give viable evidence to the differences of the emulsion applied film as to one that is acting as a nitro or other film would. If your still concerned you can always spray the other half of the glass with a pure solution of nitro or acrylic, etc.. Just make sure the coatings are all gloss to be fair ok? Specular gloss [flatting agents] definitely kill the appearance characteristics, more surface refraction = lighter looking color / less depth,less saturation of color, etc.

Your second question, The solvent /diluents, do not figure into it at all, they are merely carriers [vehicles] that allow viscosity adjustments or solutions of the resins etc. Any testing of any types of films are done when in the final state they are intended for by or in use. it is only the dried film we are concerned with at the moment ok? how could we possibly compare a milky wet solution with one that is water or crystal clear? Hm.... unless the case were such that the end use was to be that of a resin solution being kept intact permanently or long term.