Why I like Waterlox

Re: Why I like Waterlox

Brad Chenoweth

Hi Bill,

Do you use the Waterlox original?

what is it?

David Weaver

Is it a permanent cure finish? When you use the term Varnish, I'm assuming it is - I've never used it but it was the buzzword for finish suggestions on another forum.

How hard and durable is the finish?

Re: Why I like Waterlox

Bill Tindall, E.Tn.

yes original

a caution

Bill Tindall, E.Tn.

It cures quick because it must have a a lot of catalyst to promote cross link curing. This property means that a half full can of varnish, half full of air, will cure in the can. A partial can must be inerted for storage. I displace the air with nitrogen from a tank. This procedure preserves the partial containers of Waterlox.

Re: what is it?

William Duffield

It is a tung oil based varnish. While it is not quite as tough as polyurethane, it's advantage is if it is damaged, you can apply another coat and correct the problems.

Definitely listen to Bill's warning regarding polymerizing in the can. That can be a very disappointing surprise (DAMHIKT). Ellis has noted, however, that if it gels, it is still usable, if you can extract it from the can and can apply it with a rag.

Re: a caution

Brad Chenoweth

My dad's favorite finish in the 1960's & 70's was a product known as Armstrong Clear Penetrating Wood Sealer. I suspect it was similar to Waterlox, as it too would gel in the can if only partially used. We still have several pieces with this finish that have held up beautifully through the years.

space bags..

David Weaver

.I've got a bunch of space bags from cooking varnish. My varnish is several years old and it's just pine and dammar and is supposedly bad in less than 6 months.

It's still fine and will cure with UV exposure, and it hasn't gelled at all.

William is saying you can apply new finish to old, but you're talking of crosslinking and the term varnish is being thrown around.

What gives?

Re: space bags..

William Duffield

I am not a chemist, and I don't play one on TV. So, I probably have some details wrong. There are lots of chemicals that are called varnishes. The definition is now much narrower than it used to be. In general, varnishes are finishes made from long chain organic molecules that cure by cross linking. Polyurethane is a petrochemical that cross links. Other natural oils, and chemicals made from these oils, also cross link. Poyurethane evidently does this much better than others, and almost all it cross-linking or bonding sites link up to others during the curing process. This property makes it particularly tough and impermeable to physical and chemical attack. These are advantages. However, if you apply another coat, there are almost no cross-link sites available in the original coat to hook up with the new coat. This allows the new coat, even after it has cured to peel off from the previous coat. Other varnishes leave ore cross-link sites available to hook to the new coats, and therefore are more repairable. The holes in our understanding are due to the finish manufacturers hiding the actual varnishes (and other chemicals) they put in their products. So it is to a large extent, personal experiences or even lore that informs us of the different properties of the finishes we use. A lot of people like polyurethane, in spite of its disadvantages. A lot of people prefer WaterLox, in spite of its disavantages. A lot of people use BLO, in spite of… Others prefer finishes that are not loosely classified as varnishes, e.g., shellac, lacquer, acrylics, latex, epoxies, etc. If I've got some (or all) of this wrong, I'm sure Bill will be able to fix it.

Other methods...

John in New Mexico

Nitrogen is good if you have it. CO2 also works, its more common as a welding shield gas.

I always decant Waterlox into a collection of jars, right up to the rim. It keeps for years this way. I tend to put a gallon in a few large jars and decant one of those into smaller and smaller ones as needed. I've also used both ball bearings and marbles to raise the level of the Waterlox in the jar and displace the air.

Thanks to my last job, I have a lot of 1" ball bearings kicking around. Marbles are nicer to drop in a jar however. Clean with mineral spirits and reuse.

saying this as a know-nothing

David Weaver

It appears to be mostly stoddard solvent, cobalt salts and a little bit of pine resin.

The reason I say I know nothing is that it sort of looks like it has bits that a violin varnish in it, but the proportions are monstrously different (the pine/dammar varnish that I made was very heavy on resin).

Since I'm not a chemist, I have no idea what's what, but $35 a quart for what's in it seems a bit steep.

I know from reading (before making varnishes) that there are "oil varnishes" and much of what's in the public reach is more "oily" and less permanent finish part other than the oils (like the dangerous high build two part polyurethane type finishes are not similar to polyurethane in a can, and "wiping varnishes" tend to be more oily and less quick building than a pine/dammar/linseed/turpentine varnish.

But my experimenting has been somewhat limited to that because shellac works so well for hand application (and durability is a who cares when the builder lives in the house with the stuff made with it) and I haven't added japan drier yet to the varnish (the drier CAS code for cobalt salts - or the component in it - is the same as one of the codes in waterlox).

Re: It's In There

William Duffield

If you are trying to use the Safety Data Sheet as a recipe, it doesn't work, because the government only requires ingredients to be listed based on their danger, e.g., toxicity, flammability, etc. They don't even have to list chemicals (e.g., endocrine disrupters) that the government has not yet determined to be dangerous. That's probably why the actual modified tung oil varnishes are nowhere to be found.

AHHH..

David Weaver

...that explains where the solids would come from. At some point, I'll get a burr and try it.

But this discussion has reminded me of what else I should try - thinning my violin varnish and adding cobalt salt because it smells a dream and actually makes a nice almost clear finish.

I've posted this solid spruce guitar before (my apologies, I'm not prodigious enough to post new things all the time), and expected it to look "warmer". Instead, the plain violin varnish looks like instrument lacquer (without the repairability or higher hardness )

https://i.imgur.com/MuGggK8.jpg

back to my know nothingness..

David Weaver

..when you make varnish, you can control how hard the varnish is by choice of resins. I think (but not sure) you can also control its penetration by making it higher in resins. So, something like dammar would make a hard varnish, but by itself, it's a bit brittle. I think it's commonly used by artists, who probably aren't going to fold their paintings around and smack them and won't care that it dries kind of hard.

Pine and dammar seems to be a nice choice, but the amount of resin is quite a lot.

I used this recipe.

https://www.youtube.com/watch?v=gh5JTATnl4k

Damar 150grams

Calophony (pine resin) 100grams

Linseed 213grams

Liquid wood ash 250grams

Slacked Line 0.6teaspoon

Gum Turpentine 125grams

thanks to the magic of the internet, you don't have to know what slacked line is, you can just find it and buy it. I did have to burn some maple, and strain water through the ash (through a coffee filter).

it wasn't an unpleasant process, though the cooking took place outdoors (I understand that the potential fireball that occurs when the mixture starts to link has burned down plenty of buildings. I didn't get a fireball, but George said he's made a couple of small mushroom clouds in his back yard)

I guess if this wasn't enjoyable, $35 wouldn't seem that bad. Just wondering on the side, does the seeming (but not confirmed - something could be left out of the msds) focus on oils vs. resins make the waterlox stuff more penetrating and less of something that would sit on the surface (which is what the violin makers were looking for - no more than the minimum possible penetration into the wood).

Re: back to my know nothingness..

William Duffield

I am also in the realm of almost-no-nothingness regarding the properties of varnishes. And we are dealing with proprietary information and trade secrets in a competitive marketplace for goop in a can, and government regulations (or lack of them) for witch's brew you're not expected to put in your mouth and swallow. My father was a plasterer, and my uncle was a farmer, so at least I know what slaked lime is, and realized immediately that you mistyped it, which would make it a bit difficult to find with Google. The farmers around here dump tons of it on their fields every spring to correct acidity in the soil.

i copied that..

David Weaver

...from the recipe. I thought the spelling was interesting, and didn't know if it was intended based on the wig and stocking types (as in, was it called "line" at one point instead of lime?).

I remember the lime pile well (most of my relatives were farmers, too, but they weren't too exited to talk shop about farming bits with kids. We were germans - I think germans like to either have the kids doing a task to toughen them up or wait until they're old enough to have the bandwidth to talk).

(i also recall the bottle of powdered CaOH2 being about $2. Which was a pleasant surprise, because high quality turpentine wasn't nearly as cheap).

Grip Strength

Mark Mandell - Gone Round in New Jersey

You're forgetting finishes, Shellac & Lacquer, that function with 100% "burn-in".

Burn-in is the ability of a re-coat to partly dissolve the previous application so that the result is a single layer (thicker) of the resin after the solvent(s) evaporate. They don't "cure" like reactive finishes and polymerizing oils etc. The Chinese have used this property for centuries to make carved lacquer bowls and jars (not 'hollowforms') that are made of pure lacquer built up after many applications of the dissolved resin, and then carved.

The waterborne finish guys have, for lots of years, been working on getting 100% burn-in in their products. Some success was had if subsequent applications were done within a short time (usually several hours), before the carrier and tail solvents completely evaporated. The big advantage is that burned-in finishes eliminate witness lines if the film is cut back during the rub-out process.

Varnishes like polyurethane that don't re-dissolve the prior application (not ignoring the wet-on-wet method) have to be sanded for the next coat to get a good grip on the existing film.

some qualifications for the claim

Bill Tindall, E.Tn.

varnishes like polyurethane that don't re-dissolve the prior application (not ignoring the wet-on-wet method) have to be sanded for the next coat to get a good grip on the existing film.

One layer will(or won't) bond to the next depending on the curing chemistry, adhesion between layers and any mechanical interlocking due to roughness. I do not have data to support this claim but I would expect there to be sufficient unsaturation remaining in a cured varnish film formulated from "oils" to chemically bond to a layer of new finish added any time later. From smell one can tell curing chemistry is going on for days to weeks in a varnish finish. So over this time scale chemical bonding will occur.

Neither chemical bonding not mechanical bonding is necessary to get layers to stick if the surfaces stick by adhesion.

The problem with sticking to an aged surface is this aged surface is likely chemically different from what it was when freshly applied. I can think of a lot of reasons new varnish might not stick to a 5 year old finish that lived near the kitchen.

Personally I have never experienced a finishing failure due to layers of finish not bonding.

no disagreements

Bill Tindall, E.Tn.

You go it except for the part as to why urethane varnishes are tough and hard, and resistant to chemicals. It's complicated but partially dependent on the properties of the parts that are linking up during cure.

As cheap as I am......

Bill Tindall, E.Tn.

The bed I am making is similar to a Mosher bed that sells for about $4K. The bed will have $300 of walnut lumber in it. It took a pint of finish to finish it. I am not loosing sleep over the $15 the finish cost. I like the looks of the result and its application properties were found to be favorable. These are the compelling factors driving choice.

Finishing chisel handles and violins has little relevance to finishing a bed for a 10 year old.

Re: Grip Strength

William Duffield

I didn't forget them; I just decided they were beyond the scope of the discussion, which is what we currently classify as varnishes. Since most of us here are not organic chemists, I figured that even an attempt at a detailed discussion of polymerization would be over our heads. As Bill notes, "it's complicated." …way too complicated for my pay grade, and I used to read the organic chemistry section of the CRC Handbook just for fun.

Using polyurethane...

David Weaver

When building poly several coats in row, I've always applied them at intervals and skipped sanding. Mind the discussion, this may be a total of 10 items, but none had an issue.

I view the sanding between coats less as a matter of adhesion and more as something that helps make the last coat look good without sanding back a lot.

I do what Mark said for waterborne finishes with crosslinker on guitar, though - the coats are relatively far apart. Then I do the initial wetsanding and buffing of the finish before it's fully cured so that if it's thin somewhere, I can continue to spray. I've never sprayed more on something 2 days old or more.

In terms of reactivity, I had crosslinked finish at one point in the past that seemed to be mostly cured after a day and learned a lesson - I put the top of a case that was rubbed out and to be attached to my first bookcase on top of a trash can. The finish reacted with the garbage bag badly and I had to scrape it off and redo it. The reaction was very thorough (this was a stew mac WB instrument finish that's probably just one of the target products in a different can for more money).

Re: Other methods...

Tom Gattiker

Adding marbles etc to the jar.... why didn't I think of that!

I can't claim credit for that one...

John in New Mexico

Got it from a Guatemalan immigrant in a custom shop I worked for in Tucson. I was the only guy besides the boss who spoke any Spanish (albeit not nearly as well as did the boss) so I picked up a lot of info from the two immigrant woodworkers that the other guys missed. Some of it was really clever stuff like the marbles, some of it was more skill specific - the guy from Nogales Mexico was a fantastic woodworker.

Using gas to preserve finishes

John K Jordan

>>> Nitrogen is good if you have it. CO2 also works, its more common as a welding shield gas.

I’ve been using nitrogen for this for years, keep a tank in the shop. Argon works too.

Buying Bloxygen is a way to preserve finishes with gas but the cans are not cheap. However, a tank of compressed gas plus a regulator isn’t exactly free either.

Bloxygen used to contain a mixture of nitrogen, argon, and CO2. Then they discovered the CO2 can react with certain finishes. They didn’t give the details. However, they quietly quit using it and now their product contains just pure argon.

I use the nitrogen for things other than finishes so the Q tank I’m using is nearly depleted after maybe 10 years. I have a spare tank of argon I’ll switch to soon and get the empty one refilled.

Replacing the oxygen with another gas is quick, simple, and cleaner than using marbles, decanting into smaller containers or flexible plastic bags. I keep a piece of small-diameter clear plastic tubing on the regulator to direct a gentle stream of gas into the container with the lid in place but lifted just enough for the tube, ready to close quickly.

For me, the best proof of effectiveness is in several containers of TruOil. Several times I’ve had several bottles of TruOil set up quickly several times once opened. I suspect that’s the reason it’s commonly sold in very small bottles. About 5 years ago (I think) I replaced the air in several opened containers with nitrogen and they are still good.

JKJ