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View Full Version : Dont use natural oil finish on veneer?



Ronald Kot
12-16-2010, 4:04 AM
Can I use a natural oil finish on veneer?

By natural oils finish I mean tung oil, or products like oli natura, or osmo polyx oil.

I have just heard that no natural oil finish is recommended over plywood - because there is always a risk that the solvents could dis-bond the ply by breaking down the adhesive.

I was going to use a natural oil finish on a Bathroom Vanity Cabinet with a solid white oak top, but also on the cabinet which is shop sawn 1/8" thick veneer on baltic birch.

John Coloccia
12-16-2010, 7:40 AM
I've never heard this. Could you post a link where you got that from? I don't think I've ever had plywood delaminate on me for any reason except BORG plywood, but that comes half delaminated to begin with.

Larry Fox
12-16-2010, 9:59 AM
I have never heard of that either. I use BLO on veneer all the time and never had any of it fail as a result. I mostly apply my veneer with UniBond. Not much experience doing it with plywood. I agree completely with John that BORG ply is in a constant state of delamination and the process starts as soon as it leaves the factory.

Chris Padilla
12-16-2010, 11:29 AM
Can I use a natural oil finish on veneer?

By natural oils finish I mean tung oil, or products like oli natura, or osmo polyx oil.

I have just heard that no natural oil finish is recommended over plywood - because there is always a risk that the solvents could dis-bond the ply by breaking down the adhesive.

I was going to use a natural oil finish on a Bathroom Vanity Cabinet with a solid white oak top, but also on the cabinet which is shop sawn 1/8" thick veneer on baltic birch.

Well, I've used oil/varnish blends (Velvit Oil) on A-1 maple plywood that had solid maple with it (typical cabinet w/faceframe) with no delamination issue.

I also shop cut walnut veneers and used a vacuum press and good quality hard drying glue to secure them to MDF. Those veneers were 1/16" thick and I used the same Velvit Oil on them with a topcoat of clear shellac. That project is holding together just fine a year or two later.

As to 1/8" thick veneers. I would say you are on the border of that still being considered a veneer. At 1/8" thick, it is going to act more like solid wood (in terms of movement) than something much thinner. Heck, even my 1/16" thick walnut veneers pulled a 1 1/4" thick MDF panel out of flat when I veneered only one side of it. Had I not witnessed it in my own shop, I would have never believed it! For this reason, you may need to put 1/8" "veneers" on the other side of your baltic birch to balance the panel or you may have issues...especially with your finish choice.

You may wish to reconsider your finish (or final topcoat) for a bathroom vanity. Whatever oil you choose, it likely won't hold up well around water or water vapor typically found in a bathroom (or is it a half bath, maybe? Only a sink/toilet?) and so the wood is likely to move a bit. It could be an issue and is something to think about.

John Coloccia
12-16-2010, 1:33 PM
This actually brings up a good question. What does cause plywood to delaminate. I think water and heat will eventually cause problems (though I may be wrong), but what other kinds of things might cause that to happen? Just idle curiosity, I guess.

Scott Holmes
12-16-2010, 6:20 PM
Ron,

Pure oil finishes don't usually have an solvents or thinners in them. So which "oil" finish are you thinking about using? MS and the like are thinners in many finishes and I have not seen delamination caused by using it. I'm sure there could be an exception.

As for using an oil finish in a bathroom... an oil based varnish would be good protection; an oil/varnish blend not as good; a pure oil finish will be the worst of the bunch for protecting the wood from water and/or water vapor.

I too worry about your 1/8' thick veneer... causing warping. Plywoods are most always an odd number of plys to keep them balanced. Adding an 1/8" verneer to one side only will make them unbalanced and strange thing may result.

Jim Becker
12-16-2010, 9:40 PM
I have never heard that and have never had a problem with it, either. I do not use a different finishing regimen on veneer ply from solid stock.

Ronald Kot
12-17-2010, 2:37 AM
Hello,

Thank you for all your replies. My cabinet is veneered on both sides.

I am new to veneering, and this concern about oil finish solvents soaking through veneer and dissolving veneer glue came to me out of the blue from a finishing products retailer. Surfing the internet some have said this is a valid concern but their context MAY be with super thin veneers.

Its good no one has ever heard of this, but I see some oil finish product spec sheets that caution on use on veneer:

http://www.livos.co.uk/fileadmin/user_upload/livos_tm/pdf/TDS_244.pdf

As one of you pointed out, there are the more pure oil finishes, less suitable for my bathroom sink vanity top, and then there are the hybrids that mix in other stuff, waxes, and other things, perhaps more suitable for my bathroom sink vanity.

The actual product I am considering using is this one:
http://www.osmona.com/pdfs/quicksheets/QuickSheet_OSMO_PolyxOil_3054.pdf

But I have also found this one:
http://www.osmouk.com/images/POLYX%20OIL.pdf

I am currently trying to get a solid recommendation from OSMO.

I got put on to OSMO at my wood guild meeting. Some have found osmo products to be a lot less work than tung oil, durable, and maintainable. So here I was checking it out, then got the veneer delamination issue from out of the blue. Will post what I find out.

Has anyone tried OSMO products, on cabinets with veneer? I see the USA office is in Seattle.
http://www.osmona.com/
1.888.487.8054
4121 1st Avenue S.
Seattle, WA 98134
USA

Thanks, RK

John Coloccia
12-17-2010, 4:31 AM
Hello,

Thank you for all your replies. My cabinet is veneered on both sides.

I am new to veneering, and this concern about oil finish solvents soaking through veneer and dissolving veneer glue came to me out of the blue from a finishing products retailer. Surfing the internet some have said this is a valid concern but their context MAY be with super thin veneers.

Its good no one has ever heard of this, but I see some oil finish product spec sheets that caution on use on veneer:

http://www.livos.co.uk/fileadmin/user_upload/livos_tm/pdf/TDS_244.pdf


This is a classic case of lousy documentation. "Partially suitable for OSB, Multiplex and veneers. Not suitable for plywood, stained woods or cabinet interiors." No mention at all what partially suitable means or why it can't be used on cabinet interiors. Very bizarre. The product, "Reinforces and deepens the natural color of the wood grain." Who the heck does this on OSB? LOL.

Scott Holmes
12-17-2010, 11:03 AM
Ron,

After reading all their hype... my conclusion is these are new fangled "green" vegtable oil and wax mixtures that would be on par with Minwax's Thompson's Water Seal. (which Ithink is a total waste of time and money) At $36 per liter it's super expensive oil and wax; which provides very little, if any, protection from water. I don't care what their marketing guys say.

On top of that they use oils that can go rancid and they tout that there are no preservatives or biocides.

You could mix up a far superior oil/wax blend for less than $8/liter. Better still would be an oil/varnish blend that would at least protect the wood from water and vapor a lot more than and oil/wax.

John, you don't like the look of finished OSP? It's so unique... LOL

Chris Padilla
12-17-2010, 11:12 AM
Hello,

Thank you for all your replies. My cabinet is veneered on both sides.

Ron,

I think the #1 thing to do when learning about finishing is to either buy or visit your local library for the following BIBLE on finishing:

"Understanding Wood Finishing" by Bob Flexner.

You will LEARN a ton about finishing and likely save yourself a lot of time and money and get a superior finish that is suited to your situation. This book should be right there next to your paint brush and sprayer. :)

Howard Acheson
12-17-2010, 12:59 PM
>>>> What does cause plywood to delaminate.

It depends on the type of adhesive used for the laminating process. Basically there are two types of adhesive used for standard plywoods. Interior rated adhesive is generally used for decorative hardwood veneer plywood. Construction plywood like fir and pine veneer are made with exterior rated adhesives. Of course an interior rated plywood will delaminate if the plywood is subjected to frequent water soaking and/or very high, long term moisture evironment. Exterior rated plywood is not subjected to adhesive failure but long term wetting will soak the wood plies causing them to eventually rot and deteriorate. So it's the wood itself that fails, not the adhesive.

In all my years of owning a cabinet/furniture shop and my own home shop, I have never found a common finish that would cause veneer adhesion failure of commercial manufactured plywood. There are lots of adhesives that folks could use for lamination projects. Some could be adversely affected by a finish soaking through the veneer.

Ronald Kot
12-22-2010, 11:51 PM
HI,
I just started looking at Bob Flexner's excellent FIRST book. The copy I got out of my library is is written in 1994. This old version does not have anything about oil/wax finishes in it.....not around at that time I guess. Bit I see he has an updated version, maybe around 2005. So I'll look for that.

Scott Holmes
12-23-2010, 12:04 AM
More likely not mentioned in version 1 of Bob's book because oil and wax are good for cutting boards that get reapplied very often. Not a suitable finish for furniture or bath vanity doors let alone the countertop. Unless you plan to really it weekly or more often.