Interesting that you should ask about both tung oil and Timberknee. At the moment installers are putting in approximately 400 sq ft of 5" American Black Cherry that I recently purchased from Timberknee. I opted to have the flooring pre-sanded to cut down on onsite sanding. Even "dust-less" sanding equipment isn't. My only regret is that I didn't find Timberknee until long after I purchased flooring (reclaimed heart pine) from another source. If I had it to do over again, I would get all of the flooring (approximately 3400 sq ft) from Timberknee rather than take another chance on reclaimed wood flooring.

Turning to your question regarding tung oil, I will be finishing the flooring with Millie's Pentrating Tung Oil from Sutherland Welles, a polymerized tung oil thinned with a citrus-based solvent. That was a considered decision reached over the course of almost two years and despite a very positive experience with Waterlox on the antique heart pine in my prior house. My reason for switching from Waterlox to Millie's is two-fold: first, the non-toxic citrus solvent in Mille's versus the toxic ingredients in Waterlox; second, Millie's is a polymerized product and Waterlox isn't. Although I have no scientific evidence to support the utility of polymerization to strengthen the chemical bonds at the molecular level, my science-geek friends didn't scoff at the claim. That was good enough for me.

If I can figure out how to do so, I will post a picture of the flooring installed and then finished.

WmWalker

WmWalker's correct that the solvents in Millie"s and Waterlox are different but the statement about Waterlox not being a polymerized oil is misleading.

Tung oil, when it dries, bonds to itself - it polymerizes. Polymerization of a drying oil like tung oil before application is basically speeding up the drying process so that more of the solids will sit on the top of the wood (instead of soaking in) to form a thicker protective surface and shorten drying time.

Waterlox says that their product includes "resin" but synthetic resins can be made by polymerization - so both products contain oil that will penetrate and dry as well as thicker substances that won't soak in as well and will provide more of a surface finish, as well as hardening more quickly. There's no reason to believe that Millie's polymerized oil is any more durable than what's in Waterlox. It may be, but you'd only know that by testing it.

The "toxic ingredients" in Waterlox is mineral spirits that evaporate out of the finish when it's dry. Citrus solvent also evaporates and is irritating to the eyes, lungs, and skin and should - like products containing mineral spirits - be applied with good ventilation until dry.

Citrus solvent is in the same family of chemicals as turpentine, and mineral spirits were developed as a substitute for the more toxic turpentine.

Millie's may be a great product but the text describing why they're better than other tung oil products is irritatingly misleading.

I don't have any financial interest in any of them and I've used pure tung oil with citrus solvent for wood used in food prep and pure tung oil and then Waterlox for table tops. I prefer the smell of the citrus solvent but I don't get any of them near flames or use them without good ventilation.

mondragon - Please note that I wasn't positing that Millie's Penetrating Tung Oil is necessarily a better product than is Waterlox. I was simply describing the factors that went into my decision to use Millie's despite my prior positive experience with Waterlox. Resin aside (I do admit to an irrational anti-resin bias), once the solvents evaporate (or whatever it is that they do) tung oil is pretty much tung oil.

As for the solvents (citrus oil vs. mineral spirits), I found the cloyingly sweet smell of citrus far more tolerable than the sharp, harsh smell of mineral spirits. But after the initial wiff of citrus, the smell was rather overpowering. I may never peel an orange again . . . . !

WmWalker

wmwalker,

We are also going with reclaimed for our floors. Would you mind sharing the company name of the company that did not work out? I want to make sure that is not who we are using!

Let me know if you prefer to send a private email.

Teresa