07-04-2011 07:47 AM
I have some shelves that I would like to finish using Sam Maloof poly/oil finish followed by Sam Maloof oil/wax. I would also like to stain the shelves first. Does it work to apply the Maloof finishes over Min-wax stain?
07-04-2011 12:34 PM - edited 07-05-2011 03:18 AM
Sure! Will there be any benefit in doing so? Absolutely not! The Sam Maloof Poly/Oil Finish is simply a very expensive oil/varnish blend. It is composed a blend of Boiled Linseed Oil and/or Tung Oil, thinner and varnish. The varnish element is polyoneverythane and/or alkyd resin varnish. There is also a small amount of flatting agent added to dull the sheen. Current Rockler pricing for the stuff is about $40.00 per quart. If we take a look at Section 2 (Composition/Information on Ingredients) of the MSDS provided by the manufacturer we discover something very interesting. The total percentage of all of the ingredients in the can comes to a bit over 127%. Hum… how can there be 127% of anything in the can; full is 100%. Quite simply this is called wiggle room. It is an all too common approach to disclosure that allows the manufacturer to adjust the contents while at the same time maintaining a marketing posture. Is the “oil” in the oil/varnish blend more or less equally split between BLO and tung oil or is the tung oil volume reduced to reduce cost and bring about faster curing? We don’t know. Perhaps both oil components are reduced and the varnish elements increased to improve hardness and durability. We don’t know that either. All we know is that the percentages given can't be achieved since the total of all ingredients can't exceed 100%. Therefore, we are paying nearly $40.00 per quart for a finish of unknown composition.
Either which way we do know that by applying an oil/varnish blend the varnish element in the finish will create a film finish on the surface of the wood. This film finish will render the application of a blend of oil and wax ineffective at best and a waste of time and money at worst. The “sealed grain” resulting from the oil/varnish blend means that the oil/wax combination will be unable to penetrate and will easily be wiped from the surface. But again, let’s turn to the MSDS for the oil/wax finish for composition details. Here the manufacturer is a bit more forthcoming; we know that the finish is 50% BLO, 48.5% tung oil, 0.75% Carnuba Wax and 0.75 Bees Wax. The total of all components is 100%; no wiggle room here. Further, both carnuba wax and bees wax combined come to only 1.5% of the finish. In other words this stuff is effectively all oil with only a splash of wax. Applying oil over a film finish, even a weak film finish like an oil/varnish blend makes no sense. It will be quickly wiped away and what remains will soon oxidize rendering the surface dull.
An oil/varnish blend may be an appropriate finish for your shelves, depending on what you will be putting on them. But, you can make your own for a fraction of the cost, especially if you already have thinner and BLO on hand. Even commercially prepared Watco Danish Oil will yield much the same result at less than half the price; one-third the price if we toss the oil/wax finish into the equation..
07-05-2011 02:57 PM - edited 07-05-2011 02:59 PM
Thank you for your response.
While it is hard to argue the point that the Sam Maloof finishes are way too expensive I respectfully disagree with your opinion of their quality as a finish. I've tried a lot of different finishes and have gotten the best results by far with them. Your assertion that the oil wax finish can be "quickly wiped away" is simply not the case in my experience. I also disagree with your statement that Watco Danish Oil will yield much the same result. I've tried it and it's not even close.
But again, thanks for taking the time.
07-06-2011 04:48 AM - edited 07-06-2011 04:51 AM
…my issue is with the composition. By stating the maximum percentage of the various ingredients, the total of which exceeds 100%, it is obvious that the inclusion of one or more of the ingredients must be reduced. Which one or ones? On this point we can only speculate. The bottom line is that the Maloof Poly/Oil Finish is simply an oil/varnish blend. It may include BLO, tung oil, urethane resin varnish (polyurethane), alkyd resin varnish, thinner and flatting agents. But, there is nothing in the document that assures us that all of the ingredients are included. It would be possible to eliminate the tung oil and alkyd resin varnish completely, maximize the BLO, polyurethane, thinner and miscellaneous ingredients and still comply fully with the requirements of the MSDS. So again, my point was that we are paying $40.00 per quart for a finish of unknown composition.
My point about the Watco was poorly stated. I am not suggesting that you use Watco or even that it is on a par with other oil/varnish blends. The point I was attempting to make (poorly) was simply that the composition of Watco is known. The Maloof poly/Oil Finish, depending on what composition is actually employed may, in fact, be uncomfortably similar to the Watco. This is why I included the link to the article on Oil/Varnish Blends and the simplicity of making your own so you would be in control of the composition of the finish.
Finally, the issue of the ease with which a straight oil finish, or even an oil finish with a very small amount of wax added can be removed from a “sealed” surface does not easily lend itself to “experience”. We are dealing with things that cannot be touched or seen. We must therefore rely on the properties of the finish. “Oils” must be able to freely penetrate the grain (cell) structure of the wood to be effective. If they cannot penetrate the cell structure they will remain on the surface and the will be quickly wiped/worn away. Whatever oil remains will quickly oxidize. These properties are simply inherent with oil and are not dependent on what we say about them; it is what it is. The reality is that it would make more sense to apply the oil/wax blend ahead of the oil/varnish blend, though there are good reasons not to do that either.
I have no problem with an oil/varnish blend in your application. Neither do I question the “quality” of the finish/finishes you have chosen. What I question is: 1) their use in combination as you propose, and 2) the economy of the Maloof finish, especially when its composition is unknown, when compared to making your own.
07-06-2011 09:27 AM - edited 07-06-2011 09:37 AM
I need to point out something that you are missing when you look at the list of ingredients for the poly/oil. This list is shown below. What you are missing is the "<" in front of three of the indredients which of course means "less than". What we can derive from this is that these three indredients together add up to 14.3% of the total. Taking this into consideration, the total percentage adds up to 100%, not 127% as you previously stated. The percent of BLO is not "unknown", it's 35% and the percentage of Tung Oil is 32.995% .
Chemical Name Percent
Boiled Linseed Oil 35.000%
Tung Oil, Raw 32.995%
Aliphatic hydrocarbon 16.900%
Oil modified polyurethane resin <14.300%
Alkyd resin <14.300%
Amorphous precipitated silica <14.300%
Organophilic clay 0.800%
Methyl ethyl keloxime 0.050%
07-07-2011 03:59 AM - edited 07-07-2011 04:02 AM
Yes, I do know what “<” means (I also know what “>” means.) But, the inclusion of this symbol with respect to these three ingredients in the MSDS does not solve the problem. Let me explain. If we adopt your explanation we will be left with a finish that is 67.995% oil, (35% BLO, 32.995% raw tung oil), 16.9% Aliphatic hydrocarbon (thinner), 0.8% Organophilic clay, 0.05% Methyl ethyl keloxime with the remaining 14.225% made up of a combination of polyurethane, alkyd resin varnish and Amorphous precipitated silica. Or, the remaining 14.225% could be composed entirely of just one of these possible ingredients since all of them can compose up to 14.300% of the finish and “<” means that any or all of them could contribute nothing.
This is a problem. Even if we assume that the entire 14.225% consists only of varnish (polyurethane and/or alkyd resin) and there is no Amorphous precipitated silica added at all (this is a flatting agent and is not necessary in the formulation of an oil varnish blend) we have a problem. We have an oil/varnish blend that is nearly 68% oil (BLO and tung) and less than 15% varnish. This would make a very weak oil/varnish blend film that would exhibit minimal resistance to abrasion, moisture, household cleaners, solvents, etc. More important, however, it makes one of Rockler claims for the finish virtually impossible to achieve: “When used alone, you'll get a satin to semi-gloss finish…” If the varnish content of an oil/varnish blend is less than 15% and there is any flatting agent added at all (Organophilic clay) the sheen will simply not attain “satin to semi-gloss”.
Since we are already in the weeds, let’s go just a bit further. The absence of the “<” before the other ingredients does not mean that they will (must) make up the precise percentage given. It simply means that the manufacturer may include up to this volume and remain in compliance with the filing. The “<” indicates that the ingredient in question is limited to no more than the stated percentage. This simply illustrates some of the games that can be played with these documents. Click here to see another example in which we can use the ingredient percentages to arrive at totals that both exceed and fall far short of 100%. Click here to see yet another example of this sort of disclosure. A major problem with all these documents is that they tell us a little, but they don’t fully disclose the nature of the finishes we are asked to buy; they still leave far too much room for hype and outright misrepresentation.
Please note that I am not claiming either in this particular finish. In fact, the manufacturer gives us far more information than will be found in most MSDS documents that reveal only those components that are defined as “hazardous”. But, the fact remains that we don’t actually know what is in the can; we are left to make assumptions based on our understanding of the basic composition of oil/varnish blends. Armed with this information we can at least make certain judgments. In this case, if I may go back to the mowed grass, my point has been that you can make your own oil/varnish blend for far less. You can be in complete control of the varnish and oil used. You can also adjust the relative content of the ingredients to fine tune the finish to meet your objectives. For example, the morph from pure oil finish, through oil/varnish blends and wiping varnish all the way to varnish applied with a brush is a more or less continuous adjustment of ingredient proportion.
Finally, there is one small elephant standing in the corner of the room that needs to be acknowledged. How much of the $40 per quart price of this finish has to do with what is printed on the can and nothing to do with what is actually in the can? Clearly, David, you will use whatever finish you decide to use. The choice is yours. My objective, whenever possible, is simply to help you know what you are using and, when appropriate, to be aware of possible conflicts, redundancies and questionable orders of application. But again, the choice is yours…
07-07-2011 06:40 AM
You are right Steve, we really did get off into the tall weeds on this one but it was a good discussion and I learned a few things. Thank you for taking the time to share your expertise.