A ‘board foot’ is a measure of wood volume instead of linear feet. A board foot is the volume of a 1-foot piece of wood that is 1 foot wide and 1 inch thick. This translates to 144 cubic inches. So, to calculate board feet, you would use the following formula:

Thickness (inches) X Width (inches) X Length (feet) ÷ 12 = Board Feet

Or you can use this handy Board Foot Calculator:

This will give you the calculation for rough lumber. Use the rough lumber measurements in width and thickness when calculating the board feet even if the lumber has been surfaced.

Board-foot is abbreviated as FBM for "foot, board measure" and MFBM represents a thousand board-feet.

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When building a birdhouse you should consider certain design specifications. To attract particular species it is important to build your birdhouse with their specific housing requirements. The design considerations are the floor size, the depth, how high the entrance hole is above the floor, the diameter of the hole and how high the birdhouse is above the ground. Each of these are specific to a bird type or a group of bird types.

The reason that these are important is that they attempt to match the natural habitat of the bird that you are hoping to attract. The hole size and the height of the entrance hole above the floor are extremely important as these ensure the safety of nesting birds so that unwanted species can enter and/or reach the housed bird’s eggs.

Birds can be choosy when searching for the right home so it may be better to give them several options. This way they can pick the home that makes them feel the most comfortable.

The Red-Tailed Hawk, Osprey and the Great Horned Owl prefer a platform and Robins, Barn Swallows and Phoebes prefer a nesting shelf.

The birdhouse size specification chart shown here is only a general guideline. Individual birds may use houses slightly larger or smaller than the size listed below.

Continue reading 'A Bird House Specification Chart'

The dust and sap from various types of wood can be toxic and cause a variety of health concerns including respiratory issues and eye and skin irritation.

Skin irritation can be caused by contact with the wood, its dust, its bark or its sap and result in a rash or ‘irritant dermatitis’.

Eye irritation includes soreness, watering and conjunctivitis, which is inflammation of the conjunctiva, the delicate mucous membrane that lines the inner surface of the eyelids and covers the front part of the white of the eye.

Respiratory issues include runny nose, violent sneezing, blocked nose, nose bleeds, forced asthma attacks and, although rare, nasal cancer.

Symptoms usually subside when contact with the irritant is removed. However, a serious concern is when instead of just becoming irritated the body becomes sensitized. Once sensitized, the body sets up an allergic reaction, and the body may react severely if subsequently exposed to very small amounts of the wood dust. Unlike irritation, where one can continue to work with the dust once it is controlled below the level of irritation, people who become sensitized will not normally be able to continue working with the dust, no matter how low the exposure. Some wood dusts can cause asthma as an allergic reaction.

Here is a chart showing a list of some woods and their known issues. This chart first appeared in American Woodturner magazine in June of 1990 and has become a standard reference for woodworkers. Obviously, because of the vast array of tree types this list is not complete, it is unlikely that any list could. However, it still makes a great guide to wood toxicity. The key to the lettering code used is located at the bottom of the list.

Continue reading 'Wood Toxicity Is Nothing To Sneeze At'

Here is a list of different bandsaw blade widths and the minimum cut radius for each:

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The Red Oak, which has a Janka rating of 1290, is the industry benchmark for comparing the relative hardness of different wood species. Since the hardness of the wood varies with the direction of the grain, both side testing and end testing is performed on wood.

Here are some examples of various woods and their Janka Hardness Rating. Obviously, this is only a short list of all the available woods but hopefully will give a good representation of the most common ones.
Continue reading 'The Janka Hardness Scale'