It’s time for a long-overdue hardwax oil comparison. Hardwax oils have exploded in popularity over the last decade, and for good reason: a simple wipe-on, wipe-off finish that leaves a consistent, attractive surface is pretty much every woodworker’s dream. If you want a deeper dive into application technique, check out this video: How to Apply Rubio Monocoat
For a long time, Rubio Monocoat was essentially the only option in the 2-component hardwax oil category, and its premium pricing reflected that lack of competition. Fast-forward to 2023 and the landscape looks very different. Several manufacturers now offer 2-component alternatives, and it’s clear the market has shifted. It’ll be interesting to see how things continue to evolve over the next few years.
In the meantime, I put together this hardwax oil comparison using cherry and walnut samples, all cut from the same boards for consistency. The finishes tested were:
Sheen Testing
Samples were evaluated for overall sheen after both one coat and two coats. Because subtle sheen differences are difficult to capture accurately on video, we opted for blind testing with three separate people.
Results:
Marc: Walnut: Most sheen – Osmo | Least sheen – General Finishes
Jason: Walnut: Most sheen – Osmo | Least sheen – General Finishes
Nicole: Walnut: Most sheen – Osmo | Least sheen – General Finishes
Marc: Cherry: Most sheen – Osmo | Least sheen – General Finishes
Jason: Cherry: Most sheen – Osmo | Least sheen – General Finishes
Nicole: Cherry: Most sheen – Osmo | Least sheen – Unable to spot a difference
Despite the differences being subtle, the results were remarkably consistent. With one exception, all testers selected Osmo as having the most sheen and General Finishes as having the least sheen on both cherry and walnut. The remaining finishes, Rustic Lumber, Natura, and Rubio, were essentially indistinguishable.
It’s also worth noting that Osmo was the only finish to show a noticeable amount of gloss after just one coat. While all the other finishes improved with a second coat, none matched Osmo’s sheen.
Abrasion Testing
I explored several methods to test abrasion resistance in a meaningful way, but ultimately couldn’t come up with a test that produced actionable results. These finishes are non-film-forming and don’t provide significant abrasion protection beyond basic liquid resistance. In most cases, scratch durability has more to do with the wood itself than the finish.
In my view, comparing hardwax oils based on scratch resistance is a bit like debating which brand of plastic wrap makes the best suit of armor.
Liquid Testing
Each sample board was divided into six sections, with each section exposed to a different liquid or wet material for 15 minutes. Due to the level of damage observed at that point, I didn’t see a need for an overnight exposure test. For full details, you can reference the spreadsheet: Hardwax Oil Comparison – Liquid Test Spreadsheet
Results:
- Natura Onecoat – 17 (least damage)
- Rustic Lumber Finish – 24
- Rubio Monocoat – 26
- Osmo 2K Wood Oil – 28
- General Finishes – 30 (most damage)
Skin-Over Test
There’s nothing worse than opening an expensive finish only to find it has solidified in the can. To evaluate this, I tested the oil components alone, without hardener, exposing them to oxygen for 24 and 48 hours. My assumption was that finishes that set up faster would also be more prone to premature skinning in the can.
Results:
General Finishes remained liquid with no skin after 48 hours
Natura Onecoat remained liquid at 24 hours but skinned over by 48 hours
All other finishes skinned over within 24 hours
Repair Test
Repairability is one of the main selling points of hardwax oils. Unlike traditional film finishes, which require sanding through multiple layers, hardwax oils should allow for clean spot repairs.
To test this, we repaired the liquid-damaged sample boards by sanding to remove raised grain and dull the finish, focusing primarily on the damaged areas with only light scuffing around them. The surfaces were then cleaned and recoated with their respective finishes.
Results:
Every sample showed a visible repair. From some angles the repair was difficult to see, but from most vantage points it was noticeable. While these finishes are still far more repairable than traditional varnishes or polys, the repairs were not perfect, or even great. If this were a client table, the repair would not pass muster.
In practice, I usually sand and refinish the entire surface rather than attempt a localized repair. For reference, here’s the tannin remover mentioned: Rubio Tanin Remover
Conclusions
First and foremost, these finishes are more alike than they are different. This category of finishes has a fairly fixed set of characteristics, and the differences between brands are generally subtle. That said, here are the category winners:
- Most Durable: Natura Onecoat
- Best Looking: Osmo 2K Wood Oil
- Best Value: Rustic Lumber Finish
- Overall Winner: Natura Onecoat