Kiln Drying Fir Lumber

By Chas. S. Keith, Kansas City, Mo. President Central Coal and Coke Company

What are the benefits to be derived from kiln dried fir lumber ? Who are the beneficiaries ?

Ultimately the greatest beneficiary is the consumer. The building in which he invests his money is subject to no deJects which would result from the trse of unseasoned lumber. As Fir lumber shrinks 3l per cent in drying, it naturally follows that such shrinkage, if green lumber is used in construction, results in the development of defects. The effect on walls, ceilings, floors and all joints of this amount of shrinkage materially depreciate the value and increase the cost of maintenance of such building. Moisture is one of the principal elements in the propagation of decay, and if green lumber is used in construction of buildings, and is not left so the air can reach it, decay may set up, the results of which may not occur for some time, but in the end may be quite disastrous. The Forest Products Laboratory of the United States Forest Service, at Madison, Wisconsin, says, "Since wood rapidly increases in strength with the loss of moisture, higher strength values may be obtained from kiln dried than from air dried wood" and consequently also than from green wood, and therefore better for the consumer. In the case of the use of drv lumber, we have a satisfied consumer, but if he uses green lumber, as a rule, he is a dissatisfied consumer. Every satisfied consumer that the industry develops, by reasbn of properly prepared lumber, is a potential salesman, and every dissatisfied one is a potential knocker.

The dealer is a beneficiary because the product is bright and dry and is more readily merchandised; because the stock can be bulk piled without degradation or deterioration. Handling costs are reduced through the saving in cost incident to sticking when piling the lumber. It broadens his markets, reduces sales resistance, creates saving through the carrying of smaller stocks, as dry lumber is available for the job when it arrives in his yard, and there is a further saving in insurance, space rental, and handling charges. It is less costly because it does not shrink or degrade, and the dealer is able to market as per grades purchased. It satisfies the customer and creates new business for him. The dealer can afford to pay at least as much more Ior the product as he can save in-the expense of handling, and in the cost of degradation.

The manufacturer is a beneficiary, as kiln drying costs less than air drying. The degrade is less than in air dry- ittg. The lumber can be transported at less cost than green lumber. It brings higher values because it is more valuable than green lumber. It extends the markets for the product because it meets competition in quality and preparation of comparable woods. It encourages the use of lumber and discourages the use of substitute materials, the manufacturers of which capitalize the disadvantage of green lumber and advertise their .products as being non-shrinkable, and lastly, because it is profitable.

In addition to all of the above advantages, the requisite amount of stocksn to be carried at the mill is less than in air drying and consequently there is a saving of interest on stock investinent.

Kiln dryingtbf lumber has made more progress in the past three years thah was made in the last three decades.

Scientific research has developed a better understanding and control of the elements of drying. There are three such elements, viz., temperature, humidity and circulation. With a proper combination and control of these three elements, it is possible to secure ideal drying conditions with maximum results.

In underweights alone on lumber shipments since the being of our operation at Vernonia, Oregon, in Julv, been have glnnrng a 1924. the cost of investment 1924, the investment in dry kilns has already returned and as much more in increased values. and rve 30 million feet of dry lumber in storage, on which the underweights have not yet been liquidated.

In our Southern Pine operations, before this research was entered into, our averag'e degrading in kiln work was 27 per cent, while now, with improved kilns, it is less than 6 percent. In Fir we are able to hold the degrades to less than 10 per cent on Common grades, and on Clears to an average of 3 per cent, with an average of less than 6 per cent on the whole. This improved kiln drying work has enabled us to meet the competition of Southern Pine in the middle west and in some instances to secure equal or better prices. Fir lumber properly dried and prepared for the markets is a better product. Fir is given credit by the government for having practically the same tensile strength as Yellow Pine. Being all heartwood, it has longer life. It is softer and therefore easier to work. It has less resinous content and takes and holds paint better. It is lighter and therefore easier to handle. Because it does not blue sap stain and consequently can be shipped green, it has been shipped green and has lost most of its natural competition advantages.

An encased knot rvill drop out when lumber is air dried. It will hold better when kiln dried under proper control of the elements of drying

Is it not better to give the consumer what he wants, so that he will require more, than to make him suffer the degrade, and force him to use substitutes? If the product cobts more, it brings better values. The dealers and users are now asking the government to define "moisture content", making it a part of American lumber standards. so as to avoid shrinkage and degrading. The public will either insist on proper preparation of the product for consumption or use other products to serve its purposes

A new era of drying practice is already here. New inventions now in the process of being perfected in connection with an automatic control of the drying elements, viz., temperature, humidity and circulation, through the moisture content of the product itself, promise to further revolutionize the drying of lumber and remove entirely the human element, le4ving nothing to be desired in the complete and scientific control of drying operations. Those who are advanced in their purpose to succeed will avail themselves of their opportunities. Those who are not will ultimately be forced to do so through competition and this to their own advantage. A rnore general observance of proper practices will widen market opportunities to the buyer, create greater demand for the product, and change an industry now suffering financial losses to a prosperous one.