I am just starting to get into finishing. I have a pallet wine rack that will be holding wine bottles (obviously). On top of this I have several other wine related wood projects I am making.
I have been reserved in using finishes due to all the toxic labels and my my lack of experience but I know some of my projects will look infinitely better if they were finished.
What finish can I use that will be indoors and likely will be in contact with alcoholic liquids?
OK simple answer here, varnish.
While waterbased varnishes have been tested and some shown to provide very good protection from liquids containing alcohol, including red wine, a simpler broad-strokes recommendation would be oil-based varnish. As a class this product, regardless of formulation, will be alcohol-proof once fully cured.
Polyurethane is the most common recommendation these days although there are other varnishes on the market. To be honest even the cheaper products will give good performance — in terms of application, and the finish and protection provided — but as with so many things it is worth paying a little extra for one higher up the food chain.
A good follow-on Question to this would be about varnish application, assuming there isn't one already.
I have been reserved in using finishes due to all the toxic labels
The warnings on many products can be very scary but used with appropriate levels of caution they can be quite safe to use (q.v. household bleach).
With oil-based varnishes, there is really only one main concern and that is from the solvent vapours and for most people the only precaution that needs to be taken is to provide good ventilation. We should be careful about giving out what might be construed as medical advice in Answers but the data is quite clear that mineral spirits (UK: white spirit) does not pose any significant health risk to the average person who is otherwise in good health and isn't working in an enclosed space.
I do not want to write a book on this.
fully cured drying oil finishes, except ones with zinc (and other metallic) driers, are usually suitable to come into contact with food. The FDA regulates this in the US, these so-called food grade finishes are usually made from tung oil (china wood oil is another name). You will see FDA approved on the label of the product. Mineral oil is what you often see. It is not a drying oil. IMO it is a very poor wood finish. Most water based finishes have molecules that are emulsified and are not water-soluble. When the water evaporates the polymers form - acrylics or products like Hydrocote work okay with this application. These water-based finishes are kinda like drying oils in disguise. "Varnish" is kinda non-specific. It can be oil, water-based, and even catalyzed. See the KCMA thing down below.
Shellac is an evaporative finish. It gets "hard" because the solvents evaporate. When the solvent (alcohol ) contacts a cured finish, it damages the finish. Only evaporative finishes which depend on other solvents will provide a reasonable alcohol resistance. Nitrocellulose lqcquer is one. These things smell to high heaven. You must use them when ambient temps are just right, circa 70-85 degrees F, to get decent clear films. They are also not available in a lot of locales because of restrictions.
Catalytic finishes (two part lacquer or pre-catalyzed) are top of the line, but not something you can apply without a little experience and a lot of equipment. They are standard for items like kitchen cabinet door and frames - that come into accidental contact with all kinds of household chemicals. Or maybe not accidental. Example product: pre-catalyzed waterborne clear from Mohawk.
Bottom line - research the KCMA standards for finishes. Read the four-part finish test to see what KCMA finish certification means: http://www.kcma.org/Homeowners/Performance_Testing_and_Certification_Program#2
Hmm. I still got too gabby.
http://www.accessdata.fda.gov/scripts/fcn/fcnDetailNavigation.cfm?rpt=ialisting&id=3235
That link is FDA list of food contact substances (FCS list) which is what food safe deals with in the context here. Zirconium palmitate is used as a drier in drying oil finishes. I just chose that entry because it is a drier.
Follow the link back to other compounds if you want to know for yourself.
So in summary: drying oils from edible plants and seeds are edible either in dried form or as oil. Pure China wood (tung) oil, linseed oil, walnut oil, and rosemary oil all do air dry but take quite a while. So for purists, these would be a choice. The 'boiled' version of linseed oil has driers in it. Actual linseed oil, like Michelangelo had, can be had http://www.sinopia.com/VS50017-Cold-Pressed-Linseed-Oil-from-Sweden-best-grade_p_11.html
Milkpaints that you make with harmless iron oxide pigments (like red ocher) are also edible, if a little high in iron and calcium content. Milkpaint has:
casein (milk protein, quark is another name) lime - Calcium oxide (in water solution becomes hydroxide) pigment like red ocher Some people add linseed oil
TL/DR: Don't worry about the alcohol thing; pick a finish that's easy to use.
What finish can I use that will be indoors and likely will be in contact with alcoholic liquids?
I hate to write an answer that doesn't answer your specific question, but I think you're focusing on the wrong thing here. The finish that's best known for being susceptible to damage from alcohol is shellac, and that's because alcohol is a solvent for shellac. But even shellac won't be instantly and irreversible damaged by the amount of alcohol in wine, and repairing a shellac finish is relatively simple.
In reality, almost any finish could work for a wine rack. Given that, you should look for a finish that matches your experience level. Look for finishes with the following characteristics:
Start by learning a little about the various types of finishes. Here's a video from finewoodworking.com that covers the very basics. As you'll see in the video, there are a number of finishes out there where you just wipe the finish onto your project with a rag and then wipe off the excess. These types of finishes usually dry quickly and tend to be very forgiving: if you missed a spot or want to even the finish out, you can apply more; if you want to change the look, you can rub it down with steel wool or a soft rag.
Toxicity isn't usually a big concern except when you're applying finishes (you need to watch out especially for fumes from solvents). Dried/cured finishes are generally safe for most uses, and no finish materials are going to get through a wine bottle. But since you mentioned it, you might want to take a look at the finishes from Tried & True. These are all in the easy/fast/cheap/attractive category. I used the Varnish Oil on a side table I built a dozen years ago, and it continues to look great.
Finally, go with your gut. Every woodworker has his or her own favorite finish. In fact, many will talk about a finishing schedule, i.e. a whole list of finishing steps required to achieve their favorite look. The even-numbered steps generally involve application of some potion or other, and the odd-numbered steps call for application of elbow grease and some form of abrasive material. Don't be intimidated by all that -- you can get a very nice finish by just sanding, applying a single potion as described above, and optionally buffing with a cloth and maybe a touch of wax.
Strange that there are no solid replies on any of this...maybe due to the vagueness of the question. For a winerack (you are NOT eating off the surface), you are in fact, asking about 'furniture coatings'...so most anything would work (unless you are licking your furniture!) Now...I searched for a LONG TIME to find an answer to a more-specific question...'what finish should I use on a WOODEN BEER MUG that doubles as a RUM-BASED GROG MUG?' Now, we're talking about direct-contact FOOD APPLICATIONS! To answer the question, 'what should I line my mug with, which will be exposed to mouth-contact and ethanol'...the answer comes down to ONLY ONE ANSWER: Polyurethane. Polyurethane (once cured...30 days) is essentially a 'plastic', no different than a plastic cup or mug. It is considered by the U.S. Food-and-Drug-Administration as 'non-hazardous' for food contact applications, and other than the caveat that when dealing with polyurethane (especially water-based), you don't want it to 'soak'...make sure that you at least 'dump and allow draining' immediately after use (don't throw it into a standing sink of water for 2-weeks before you decide it's time to wash the dishes). This all came about because the wife spent $30 on six REAL coconut cups/mugs, that were 'finished raw' (sanded smooth, but nothing else)...a drop of water and BOOM! They crack instantly! A day of research, a can of Varathane, and WOW!!! Nice looking, better color, waterproof, and work like perfection now.
Shellac will dissolved when it is in contact with alcohol. Oils and stains will not protect the piece from liquids (will stain or get rings). Polyurethane may be your best bet.
