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Mark Meckes
7th October 2004, 03:55 PM
Information and educational resources on the internet:
From Toolbase.org (http://www.toolbase.org/tertiaryT.asp?TrackID=&CategoryID=1288&DocumentID=4450)
PREPARED BY: Forest Products Laboratory - Madison, Wisconsin
PREPARED FOR: PATH - Partnership for the Advancement of Technology in Housing - Washington, DC
May 2000

Finishes for Butcher Blocks, Countertops, and Wooden Utensils

The durability and beauty of wood make it an attractive material for butcher blocks, countertops, and other items used to serve or prepare food. Wood also tends to be less prone to harbor bacteria than are some other materials such as plastic.

Finishes enhance the beauty and extend the useful life of wood. Water-repellent finishes will reduce the effects of moisture. When wood soaks up water, it swells; when it dries out, it shrinks. If the wood dries out rapidly, its surface dries faster than the inside, resulting in cracks and checks.

Finishes that repel water will reduce the effects of brief periods of moisture (washing) and repel liquids, making the wood easier to clean. Wooden salad bowls, spoons, forks, and other utensils need a finish that also resists abrasion, acids, and stains. Finished wood countertops are less likely to show stains, such as those from grape juice. There are two types of finishes, film forming and penetrating.

Finishes that form a film on wood, such as varnish, lacquer, and shellac, are also called coating finishes. Although the film protects the wood, it eventually chips, peels, or cracks. Penetrating finishes come in two types, drying oils and nondrying oils.

Drying Oils

Drying oils penetrate the wood and harden the material. They include linseed, tung, and diluted varnish. Also called wood sealers, drying oils are one of the most satisfactory finishes for wood surfaces. They reduce water absorption and make the surface easy to clean and resistant to scratches. Wood sealers are easy to apply, requiring less skill than other finishes. Worn places in the finish may be patched without showing lapmarks around the edges, which ordinarily cannot be done with other types of finishes.

Nondrying Oils

Nondrying oils simply penetrate the wood. They include vegetable and mineral oils. Vegetable oils (e.g., olive, corn, peanut, safflower) are edible and are sometimes used to finish wood utensils. Walnut oil is particularly suitable. The natural nondrying oils are applied heavily in several coats and can be refurbished easily. Vegetable oils eventually become rancid. Although this condition is not hazardous, it may impart an undesirable odor or flavor. Treated wood utensils should be allowed to dry thoroughly for several weeks before use.

Mineral (or paraffin) oil is a nondrying oil from petroleum that has been used as a penetrating finish for wood utensils. Baby oil should not be used because it contains some ingredients that should not come in contact with food.

Paraffin Wax

One of the simplest ways to finish wood utensils, especially countertops, butcher blocks, and cutting boards, is to apply melted paraffin wax (the type used for home canning). Melt the wax in a doubleboiler over hot water and liberally brush on the wood surface. Excess wax may be left on or scraped off as desired. Heating the excess wax on the surface with an old iron (similar to waxing skis) helps improve absorption of the wax.

Precautions

Whatever finish you choose, be sure that the finish is safe and nontoxic. Also be sure the finish you select is recommended for use with food or described as food grade.

For information on the safety and toxicity of any finish, check the label, contact the manufacturer.

Mark Meckes
7th October 2004, 04:03 PM
A posting at
Sam Allen's Woodworking Bulletin Board (http://www.samallen.com/wwwboard/messages/508.html )
See also follow-up posts

Non-Toxic Finishes For Cutting Boards, Salad Bowls and Toys

Posted by Sam Allen on December 09, 1997

"There are several options for finishing a cutting board or anything that requires a non-toxic finish (toys for example).

You can use a special cutting board oil or salad bowl finish. Behlens Salad Bowl Finish is one product that is safe for food contact after drying.

Walnut oil is another option. It is a true drying oil that reacts with the air and hardens, it is available grocery stores or some mail order woodworking supply stores.

Shellac is non-toxic when it is dry according to the A.F. Suter Co. (one of the world leaders in shellac production), in fact shellac is used by pharmaceutical companies as a pill coating and it is used in candy and fruit coatings.

Pure Tung Oil is non toxic if it doesn't contain dryers or solvents. Don't use tung oil products that are mixtures containing toxic dryers dyes or solvents.

Watco says its oils are safe for food or toy use after they've dried for 30 days

Water-based polyurethanes are often non-toxic when dry check the label to make sure."

Mark Meckes
7th October 2004, 04:09 PM
From woodfinishsupply.com (http://www.woodfinishsupply.com/SaladBowl.html )

Behlen Salad Bowl Finish

Salad Bowl Finish has been specially formulated to meet government standards of CFR21, 175.300 to create a nontoxic, safe for food content (in its cured state) finish.

Salad Bowl Finish has the application ease of an oil finish (just use a clean white cloth) and the film building and sheen producing (up to a satin) qualities of a varnish.

Salad Bowl Finish may be applied to wooden: Furniture (Highchairs, Cribs, Etc.)

* Utensils (Spoons)
* Food Service Platters
* Sushi Platters
* Infant Furniture, High Chairs
* Recreational Objects (Games, Puzzles, Childrens Toys)
* &, of course, Salad Bowls


Salad Bowl Finish is a specially formulated finish with the application ease of an oil finish and the sheen building and resistance properties of a varnish. Wooden bowls, wooden utensils, counter tops and recreational related objects (games, puzzles, etc.) when finished with Salad Bowl may be used in contact with foods.
* It's great for furniture too!


Procedure To Apply Salad Bowl Finish:


1. Sand Wood to 320 grit smooth.
2. Remove all dust with tack cloth or vacuum hose.
3. Apply Salad Bowl Finish to wood with lint free white cloth.
4. Apply one thin, uniform coat.
5. Allow 6 hours dry time before recoating, lightly scuff sand with 400 grit sandpaper.
6. To recoat, repeat steps 2 through 5.
7. Apply enough coats to thoroughly seal the surface,
8. softer or open pore woods may need several coats.
9. Allow 24 hours prior to rubbing with nylon mesh pad or 4/0 Steel Wool.
10. Allow at least 72 hours curing prior to use with food.
11. Clean-up with Mineral Spirits.
12. To insure that materials coated with Salad Bowl Finish
may be used in contact with food, you must do the following:
1. Apply to raw (non-stained) wood.
2. Use as is (Salad Bowl Finish is a ready to use product), do not add reducers.
3. Use only additional coats of Salad Bowl Finish to build a finish
(do not apply over other finishes).
4. Wait at least 72 hours, observing proper curing conditions,
to allow all detectable traces of the Mineral Spirits solvent to evaporate.