Is Rubio Monocoat Waterproof?

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When you find a product you really like and find it useful in many ways in your woodworking shop, you tend to stay with it. Such is the case with Rubio Monocoat Oil Plus. We use it, and we’ve written about it often in the past couple of months, including here, here, and here.

We’ve determined it is, in fact, a one-coat product, and we’ve determined it is food safety compliant. We know how long it takes to dry and cure, and we know it can be used over epoxy. We use it, and we like it.

Let’s discuss Rubio Monocoat for a few minutes and then get on to the question of the day in this article.

What is Rubio Monocoat?

Rubio Monocoat is a hard-wax and linseed oil finish for all types of woods that colors and provides a protective layer on woods in a single application. Its effectiveness is a result of bonding with wood fiber at the molecular level. It penetrates deeply into the wood and offers protection from heat, water, and daily foot traffic, making it an excellent choice for furniture and flooring.

It’s a very easy application after the wood is fully and adequately prepared and cleaned. It comes in 55 standard colors and forms a terrific protective layer and durable finish that allows the natural beauty of the wood to show through.

It is also 100% VOC-free. Volatile organic compounds (VOC) are often found in products we use to build and maintain homes. Once there, the compounds are released into the air we breathe in our home environment. It also contains no water or solvents.

Unlike polyurethane, which will form a film plastic coating on wood, Rubio Monocoat is absorbed into the wood to form that molecular bond. As such, it does not necessarily require a top coat, although Rubio does produce and offer one for use on top of it. That top coat product will intensify the color and, if brushed before it dries, will enhance the sheen.

Rubio Monocoat has been determined after independent testing to satisfy food compliance standards and can be used on wood countertops in your kitchen and on serving platters and charcuterie boards. It’s not safe on cutting boards, though, as knives can cut deeper than its penetration into the wood, creating opportunities for food to become lodged and bacteria to form.

As a floor finish, it’s a great choice. It is easily and quickly applied and, once dry and cured, will form a durable protective layer that can withstand daily foot traffic.

Rubio’s claim of 80% dry in 2 days is pretty accurate with good ventilation, followed by a full cure in 6-7 days. This assumes you use the accompanying accelerator; otherwise, the dry and cure time is extended by 3 times. Why wouldn’t you use it, though – – it comes with the container of Monocoat, and with an easy 3-to-1 mixing ratio and a good stir, it won’t slow you down at all.

For furniture products, that’s an easy wait. You simply don’t use the furniture until it’s dry and cured. For hardwood flooring, though, a little bit of caution is advised. Covering walking paths during that drying/curing time, and waiting until then to use area rugs, will allow the finish to do its thing. After that, normal use can resume on a floor that has a lovely sheen and great color that allows the natural beauty and grain of the wood to show through.

Why is Rubio Monocoat Popular?

Rubio Monocoat Oil Plus 2C, 350 Milliliters, Pure, Interior Wood Stain and…
  • ONE LAYER: Rubio Monocoat’s hardwax oil protects and colors interior wood in one single layer. This…
  • PROTECTS ALL WOOD TYPES: Oil Plus 2C can be applied to almost all wood types and has great wear,…
  • ECOLOGICAL WOOD TREATMENT – 0% VOC: Only a small amount of wood oil is required for the durable…

There’s a lot to recommend when it comes to a Rubio Monocoat finish on your project or floor. We’ve touched upon those reasons, but let’s give you a partial list:

It preserves the natural beauty of the wood. It preserves the grain well, and if properly prepared before application, that grain will show through brilliantly. This is important, for instance, if the table you are making is a single-slap piece of wood that will be the showcase of your dining room or office. This artform woodworking style popular today is perfect for Rubio Monocoat.

It protects the furniture and floor well. Not only does it look good, but it also wears well. This durable finish protects well from physical and chemical damage, making it an excellent choice for flooring. There are other choices, of course, that will offer some measure of protection – other oil-based finishes like Danish Oil, linseed, tung – but do not toughen wood like Rubio Monocoat does, making furniture and floors susceptible to more scratches and dings.

It is environmentally friendly. It’s produced entirely from plant-based materials and is 100% VOC-free. This latter trait is important because VOCs are known carcinogens that you do not want to be breathing into your body.

It is easy to maintain and repair. While some finishes, like lacquers, are more durable, they are less easy to repair. With Rubio Monocoat, localized scratches and dings are spot-cleaned without the necessity of stripping the entire workpiece and refinishing. Even a wine stain is easily removed with Rubio Soap.

While Rubio Monocoat is more expensive than other wood finishes, a little goes a long way. When mixing it with the accompanying accelerator, be sure to mix only what you will need for each use, as it does not sit well on the shelf after being mixed. You also have the added benefit of needing only the single coat – it really does live up to its name.

Applying Rubio Monocoat

It also does require greater wood preparation before application. You do want your wood surface to be smooth, of course, but not too smooth. By that, we mean you should only go as fine as 180-grit, if not stopping at 150-grit. Any finer and the wood pores become smaller and tighter, and the absorption is diminished. You want deep penetration for the best level of protection.

Cleaning the sanded wood surface is also critical. Vacuuming, wiping with mineral spirits, and drying fully are important. Rubio Monocoat bonds with all wood fibers at the molecular level, and if there is saw dust or other wood fibers on the surface of the workpiece, it’s going to bond to them and not penetrate. You’d have to begin the finishing process over again if that were to happen.

If you follow that rule, though, Rubio Monocoat becomes an easy finish.

After sanding, you could also water-bloom – spray water on the surface to let the grain rise a little, and then sand down again. This will beautify the grain, and as we have noted earlier, Rubio Monocoat allows the natural grain and beauty of the wood show through well.

While Rubio does offer its own cleaning product, it too is expensive and smells much like mineral spirits. You can easily save money and simply use mineral spirits to give a good cleaning to the wood.

After that cleaning, use a foam brush, a Scotch Brite white pad, or a plastic paddle to apply. Don’t apply any more than you can finish in 15-minute increments, as after that, the Rubio Monocoat becomes difficult to remove.

Once the surface is coated, use a white pad on a power sander to buff the surface. This will spread the finish evenly over the entire wood surface and drive it deeper into the wood.

After the wood has absorbed its limit, the leftover unabsorbed finish will simply sit there waiting for you to remove it. A small buff will accomplish this, and a clean cloth will wipe away any lingering excess after that. Then, don’t touch it for at least 24 hours, and 36 hours is better. Even with the accelerator, it will be another week before it is fully cured and the furniture is ready for use, and the floor will be ready for that furniture, area rugs, and full use.

Finally, Rubio’s product statement indicates that Monocoat is:

  • Easy to apply, with no overlaps or starting marks.
  • Easy to maintain, and Rubio even offers a Universal Maintenance Oil for ongoing care. It will increase the sheen and keep it looking freshly finished.
  • Usable on all types of woods.
  • Very wear-resistant.
  • Water and heat resistant, so ideal for kitchens and bathrooms.

Is Rubio Monocoat Water-Resistant or Waterproof?

That is the question this article asks and will answer. Water-resistant and waterproof are different, and that might make a difference in your choice of finish for your project. But, in this case, it shouldn’t.

We say that for a couple of reasons. Water does bead up on Rubio Monocoat, as does oil, and even Coca-Cola will bead. A paper towel can be used to wick away the water, and a cloth will dry it.

It’s important to note, too, that Rubio produces and offers a soap for cleaning pieces that have been finished with Monocoat. It is effective and will remove most stains from any liquids.

We watched a video that involved testing the water resistance and waterproof qualities of several finishes, including polyurethane, wipe-on polyurethane, mineral oil, and Rubio Monocoat. Each piece of wood, a soft pine, was then tested with water, oil, red wine, and Coke.

The results were telling. We know that polyurethane is waterproof, and that showed in the testing. Its hard, plastic film coating on wood surfaces will repel water easily. We were a little surprised that wipe-on polyurethane was not as effective, especially with the wine test.

But, we were not surprised that Rubio Monocoat effectively repelled water, oil, and Coke. Rather than tell you about the testing, you can see it for yourself in this video.

With the effectiveness of washing with soap on the only liquid that left a stain, we’re satisfied that Rubio Monocoat will protect our furniture projects from water, oil, and Coke, at least. Even the red wine mark was removed with soap.

Rubio Monocoat may not be a waterproof finish, and even Rubio itself makes no such claim; it is highly water-resistant, bordering on waterproof. It cleans up well to the most stubborn stain of red wine, and that’s good enough for us. We suggest it can be good enough for you, too.

Last update on 2024-04-13 / Affiliate links / Images from Amazon Product Advertising API

2 thoughts on “Is Rubio Monocoat Waterproof?”

  1. Matt,
    I read with interest your thoughts on Rubio Monocoat. I have a concern that I would like your opinion on. Rubio can only be applied to wood sanded to a 120 grit finish. On my table tops of quarter sawn white oak I routinely finish to a 400 grit finish. This brings out all the grain detail
    as you know. Is the Rubio product worth sacrificing the beauty of the wood grain? I contacted Rubio and was informed that it will not perform on a finish that fine. Do you have any thoughts on this aspect of the product. Many thanks.
    Tom D.

    • Personally, I use Rubio on all my furniture projects, it’s just so easy to use and hard to mess up. Plus it’s easy to fix if you do run into any issues down the road. I usually sand to 180 and never had a problem.


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