Finishing 101: Common Terms

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DCBluesman

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Let me start by saying that I am not a world renowned expert on finishes, but there is a significant amount of misinformation being spread which can confused anyone new to woodworking.

As regards an earlier posting about carnauba wax, it does NOT contain bees wax. Maybe the specific product you have is a combination, but carnauba wax is obtained from the leaves of the plant Copernica Cerifera, which grows only in northeastern Brazil. The leaves are boiled in water, the wax floats to the surfaces and is skimmed off and filtered. It does contain trace amounts of acid that can, over time, damage certain woods and finishes. It is most often used over another finish to add hardness, however, it does require reapplication from time to time.

As regards shellac, the basic material comes from the Coccus lacca, a scale insect that feeds on certain trees in India and southern Asia. After feeding, the insect produces through its pores a gummy substance which hardens into a protective covering called lac. This lac is collected and then it is crushed, washed and dried. After further treatment, it is skillfully drawn into thin sheets of finished shellac. When mixed with alcohol, shellac forms ordinary varnish. Lacquer is the term popularly used for some commercially prepared clear or pigmented varnishes.

Lacquer comes in two primary solutions, solvent-based and water-based. Do not let the label "water-based" fool you. These products still contain solvents, only the solvents tend to be in much lower quantities and typically are not on EPA's VOC list of hazardous materials. Over time, restrictions on solvent-based lacquers can be expected to increase, probably starting in Canada and California.

CA or cyanoacrylate is acrylic resin that cures (forms its strongest bond) almost instantly. The only trigger it requires is the hydroxyl ions in water, which is convenient since virtually any object you might wish to glue will have at least trace amounts of water on its surface. Cyanoacrylate molecules link up when they come into contact with water, and they whip around in chains to form a durable plastic mesh. The glue thickens and hardens until the thrashing molecular strands can no longer move. Cyanoacrylate glues are moderately toxic by skin or eye contact. They can glue the skin together or glue the skin and other materials together, sometimes requiring surgical separation. Acetone can be used to break these bonds. Eye contact can cause severe eye irritation. Their long term hazards are not well studied, especially with respect to inhalation.

None of this is meant to promote one form of finish over another, but knowledge of the facts can at least help in guiding decision-making.
 
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NAH

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I'll add a little if you don't mind.
Shellac is normally bought and stored as a dry flake due to it's short shelf life when in solution. The solvent is also specifically "denatured alcohol." It has a very fast dry time due to the speed with wich the solvent evaporates.
Lacquer also has a fairly fast dry time, but not as fast as shellac. It also has a longer shelf life in solution. High quality solvent based lacquer is often called "nitrocellulose lacquer" for its solvent. Nitrocellulose is also known as "guncotten" and is highly explosive, but is not normally a problem in the dry finish, caution is sugested during sanding however. Nitrocellulose lacquer is normally used in a spray application, but wipe on products(Daft) can be used to produce acceptable results. Lacquer does not perform well in the presence of water vapor and may "blush"(develop cloudy white spots). This has been known to happen with high ambient humidity and when using air which is compressed into a tank to spray it.

Sorry it's mostly about lacquer, but that's my weapon of choice.
NAH
 

NAH

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I don't know enough about WB lacquers to compare quality, but I do know that almost all the hand made instruments like violins and guitars I've seen have used nitro lacquer. I hope some one could comment on the quality of a WB lacquer compared to nitro, as to it's clarity, depth, and hardness. I use nitro lacquer because it was what I had seen to be the best in the past, but I've not had much contact with WB. I would not suggest using most other forms of lacquer though, they tend to not have the same quality level. The danger is not unmanagable as long as you understand what you are dealing with. Don't allow dust to collect, don't work near any heat source, and wear a high quality dust mask. I personally sand outside to avoid any problems of dust build up. It's like everything we do, there is a risk associated with it, but if you understand the risk and take appropriate measures then it can be mitigated.
NAH
 

William Young

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My 2 ¢ worth on this one.
I know there are peole that are a little shy about using WB laquer. Just the word *water* associated with *wood* in the same sentence scares the hell out of them. But there are so many great formulations of WB laquers if choosing the industrial qualities that the "water" part of it has to be ignored. High quality WB laquer does not raise grain in wood like some immediately suspect it will. That is a myth. At least not any more than any other finish on bare wood that I have used and I have used lots of them over the years.
Good quality WB laquer provides a more durable finish than nitrocellulose laquers and dries just as fast if not faster and does not have all the health risks of the SB ones . When I was building and restoring and custom finishing guitars in another life, WB laquer was unheard of because I am ancient :). But I now wish it had been available back then . I blew up a (so called) explosion proof motor spraying that stuff one day and I have had ear damage ever since from the sound of the explosion. I was lucky I didn't loose my house and shop. I just underwent "another" eardrum replacement surgery last year because of what happened way back then. And even with a spray booth and proper respirator, it has caused permanent lung damage to say nothing of the brain cells it destroyed. I'm lucky I have two left ;-)
Nitrocellulose laquer is nothing to be fooled around with. Everyone thinks these things wont happen to them but unless you have a "proper" certified and inspected and approved and vented spray booth system worth megabucks , you are probably in danger.
In canada , there is a growing trend to the erradication of both solvent based paints and solvent based laquers. I beleive it is only a matter of time until only WB finishes will be available whether it be painting your house or boat or finishing your pens..

Way back when I was in the music business, all the imported guitars were using urethanes for finishes and they didn't sound as good as the American made instruments they were copying. They even looked like a plastic finish rather than a laquer finish. Now they are using WB laquer and their sound is approaching and in many cases , almost equal to world famous names like Martin, Gibson, Gretch, Fender, etc.
Sorry to ramble on but maybe some members here will now understand why I have done my research on laquers as well as having hands on experience with it and why I never have much good to say about nitrocellulous laquers like Deft .. etc.
If you insist on using that stuff before it is rightfully outlawed, , .. PLEASE .. be .. VERY carefull.

I started with my 2¢ worth . Talk about inflation. That was probably more than 5 ¢ worth ;-)
W.Y.
 

timdaleiden

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This is all very interesting. I happen to suffer from an odd affliction called FOD, that is shorthand for "finish obsessive disorder". [:p]

I have tried most, (not quite all) of the methods for pen finishing with varying degrees of success.

I wonder why nobody has brought up urethane finishes??? There are a growing number of water based urethanes out there. They dry quickly, and grain raising is dealt with by using a sealer first.

Anyway, there are basically two schools of thought on pen finishes, the way that I see it.

Polish the wood, and apply a friction polish. The finish will wear off rather soon, but you still have a somewhat shiny, nice looking pen.

The second method involves encapsulating the pen in a hard layer of clear material, and depending on what you use, and a number of other factors, may become damaged, and look rather bad. This second method has the advantage of showing great depth, or chatoyance, while it is still in good condition.

I have used...MM/sealer/friction polish/ren wax/buffed...CA/MM/buffed...CA/Watco Danish/buffed...Deft spray...Oil Poly Spray...CA/Deft...and I think there were some others too. I think I am going to try Minwax WB urethane next. I did mention I have an illness right?[:p]

Quite frankly, I have never heard of a WB laquer before it came up here. I was assuming it was a mis-identification of the urethanes. I did a google search on them, and found a very small number of options. When will it show up in a local store?? Or has it already??


You see I am on a quest...I seek the Holy Grail...of pen finishes.
 

penhead

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Out of curiousity, I just phoned my SherwinWilliams local store and asked if they carried 'water based lacquer'. I was told he did not carry any lacquer that was 'water based'. He did, however, say that the store had a clear lacquer that was 'water born' [sic.?], but all lacquer was solvent based.

John Payton
 

DCBluesman

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Polyurethane finishes are among the most brilliant in the furniture industry. They are long lasting and can maintain a gloss for many years. Keep in mind, though, that you are encapsulating your pen in plastic. For the average hobbyist, there are significant risks associated with their use. It’s not the urethane that is the problem, but the catalysts and stabilizers. These are often the same as those used with solvent based lacquers (including nitrocellulose lacquer). If you must use these products, take every precaution against inhalation, skin contact, and use around heat or sources of fire.

And before someone asks, I don’t see a problem in using polyurethane glues, as 1) the product is not left open long enough to create significant concentration of vapors, and 2) it is not used in large quantities, typically, for this use. BUT, be careful to clean it off of your hands immediately. It can cause significant rashes, akin to poison ivy rashes, that can last from days to weeks. Not on everyone, but on those who might be allergic.
 
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