Choice of finish for a specific set of criteria

[Stan Spencer]

This is my first post here. I have a business on the side I have been working on for a few years, and am now starting to get some traction. The product consists of 1/4" x 4'x8' sheets with wood veneer on both sides with an MDF core, and then solid hardwood matching the species of the panel. The veneers I am currently using are maple, cherry, beech, walnut, mahogany, sapele, and a solid, 3-ply bamboo. I cut the desired shape from the panel with a CNC router. I have mainly used WATCO Danish oil for my prototypes but it takes too long to cure, offers little protection, and attracts sawdust from the shop. I have spent some time on this forum and others trying to better understand the options.

The constraints are:

• It needs to dry fairly quickly between coats, ideally less than an hour, with curing time being less than 24-48 hours, before it goes in the box to be shipped.
• Shipping might take 3-5 days and when the customer opens the box, they shouldn't be overpowered by the smell of the wood finish.
• It also should offer some UV protection. The customer's environment will typically be an office and the wood product is a vertical surface, so not high wear, or touch.
• It can be wiped on or sprayed. I have no experience with spraying.
• Ideally comes in larger container sizes and/or are available at wholesale pricing.

In my research and testing, I have narrowed down to:

1. Water-based varnish. I bought a gallon of EM8000 to test.
2. Wipe-on poly. I have tested the Watco version and really like it. Unfortunately the two options I have found, Watco and Minwax, only come in small containers.
3. Shellac.

I appreciate your time and opinions on this.

[Prashun Patel]

I'd use a waterbased varnish, like the EM8000. It won't be 'cured' for upwards of a month, but it will dry fairly hard within an hour and will be ready to ship within a day. It also does not off-gas. You'll have to choose one with a UV protector though. I don't know that EM8000 is such a beast. Perhaps try EM9300.

I would certainly invest in an HVLP sprayer for this. It will make for a quicker, more professional looking finish.

Shellac and lacquer will dry hard in a short time too, but they will not offer much in terms of UV resistance. They are also more dangerous to spray and therefore more critically dependent on a good ventilated spray area.

[Maurice Mcmurry]

Welcome! I am a newbie as well. I am not getting a clear picture of what you are making. Shellac meets your listed criteria fairly well. My favorite wipe on product is Watco Butcher Block Oil. The drying time is longer. It comes in pints. "Master Gel" seems to have become "Pour and Wipe". I am not finding availability for either.

[John TenEyck]

Your criteria just scream Rubio Monocoat, Osmo PolyOx, or another hardwax oil. I've only used RM, however. Wipe on, absolutely idiot proof, low/no odor, very durable. Dust is not an issue, it's cured well enough to box in 24 hours, and fully cured (per the manufacturer and my testing confirms it's very good) in 5 days. Appears expensive at first, but it's not because a little goes a long ways.

John

[Mike Monroe]

+1 on John's comment. First thing I thought of after reading your requirements was Rubio Monocoat 2c.

[Stan Spencer]

Thanks for everyone's input. Taking into account the minimum coverage listed on each product, and the price, Shellac comes in at $0.13/sq.ft., Wipe-on poly at $0.30, and Rubio monocoat at $0.42. I couldn't find coverage info for the EM8000. It sounds like you think the extra cost per unit area is worth it. I'll give it a try.

[Dennis Jarchow]

EM8000 coverage is about 400 sq. feet at 3mils thick wet assuming no overspray. If spraying, you would normally apply 3-4 coats at 2 mils thick wet. I would think another constraint would be how long it takes you to apply the finish. You don't say how large these pieces are or how many you produce at a time, but if your volume is high enough, spraying would be faster than a wipe on or a brushed finish. You would also have the issue of cleanup of the sprayer, and the potential need for a spray booth/ventilation.

[Prashun Patel]

I had forgotten about Rubio or other “hard wax oils”. I change my vote. They are easy. Imho the extra cost is worth it unless you are going for a filmy finish.

[John TenEyck]

EM8000 coverage is about 400 sq. feet at 3mils thick wet assuming no overspray. If spraying, you would normally apply 3-4 coats at 2 mils thick wet. I would think another constraint would be how long it takes you to apply the finish. You don't say how large these pieces are or how many you produce at a time, but if your volume is high enough, spraying would be faster than a wipe on or a brushed finish. You would also have the issue of cleanup of the sprayer, and the potential need for a spray booth/ventilation.

Two or three sprayed on coats takes a lot longer, start to finish, than one wiped on coat of RM. Or did you mean to say "spraying would NOT be faster ....?

John

[Dennis Jarchow]

John,

You are correct. One wiped on coat would not be faster than spraying, especially if using a small HVLP or a detail gun. I wasn't thinking about Robio when I replied. If he was spraying industrial coatings, which some can get by with just two coats, using an airless or an air assisted airless you could move pretty fast and probably get them sprayed and packed the same day.

[Jim Becker]

For those in favor of spraying don't forget that it's not just the time to spray the finish, but also the time to cleanup, etc. RM and similar products are "one and done", more or less, but it's not likely a good idea to pack stuff up until sometime the next day. Even with the sprayed waterborne, it's still likely a good idea to wait until the next day before packing for shipment so that the finish can get to that good, initial hardening.

To be clear, I'm a fan of spraying waterborne finishes and most of what I make involves that. But I'm still giving RM some serious consideration at this point for both convenience and because I really can't spray right now until I have a new shop building up.

[Stan Spencer]

My panels are just under 3 sq.ft. and there are two per assembly, finished one side per panel. There are also solid wood 2" wide stringers that tie the two panels together which need to be finished. After finishing, I glue the stringers to the panels. Hopefully there isn't an issue with gluing after applying a finish (I use 23ga brad nails to hold them together while the glue cures). I have been thinking that spraying is the way to go long-term because of speed, but what I hear everyone saying is that applying one coat of rubio by hand will be quicker than spraying 3 coats of something else, especially when factoring in cleaning the gun and equipment. My cost numbers earlier also assumed 1 coat of each product, so if rubio is only one, it also makes it more cost effective, as well as quicker, than the others. Let me know if I got any of this wrong. Thanks again!

[Jim Becker]

Finish in the area where there is a glue line can be problematic for many kinds of glues. PVA, for example, needs to be able to get into the wood surface to do what it does. Finish keeps it from doing that. So you should mask off any area that will be a glue surface for best results.

[Stan Spencer]

I finally got some Rubio Monocoat Oil Plus 2C Pure and tried it today. I am a believer! My experience is probably like others when you first encounter it--shock at the cost, and disbelief that it will cover the amount stated, in one coat no less. But it did. My panels are almost 3 sq.ft. and 1-2 drops was enough. Some species are more thirsty than others but not dramatically.

Thank you all for recommending it. I wouldn't have tried it otherwise simply due to the cost.

I have two more questions:
1. How do you apply it? I used compressed air to blow off the panel, then used a 0000 3M scotch pad, rubbed it in, then wiped off the excess with a lint-free shop towel. Would a handheld buffer speed things up? Other methods? I didn't use the wipe-on cleaner or a vacuum beforehand.
2. I've spent some time researching other hardwax oils--there are less expensive brands, but nothing that states that one coat is all that is needed. Has anyone found anything else I should consider? Are there wholesale suppliers for Monocoat?

If you are interested, this is my product: https://blokaloks.com/

Thanks again everyone!