The segregation of white fir for kiln drying

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California Forest and Range Experiment Station , Berkeley, Calif
Drying, Abies concolor, L
Statementby Harvey H. Smith and John R. Dittman
SeriesResearch note / California Forest and Range Experiment Station -- no. 167, Research note (California Forest and Range Experiment Station) -- no. 167.
ContributionsDittman, John R., joint author, Pacific Southwest Forest and Range Experiment Station (Berkeley, Calif.), California Forest and Range Experiment Station
The Physical Object
Pagination6 p. :
ID Numbers
Open LibraryOL25577527M
OCLC/WorldCa609897169

An illustration of an open book. Books. An illustration of two cells of a film strip. Video. An illustration of an audio speaker.

Audio. An illustration of a " floppy disk. Software. An illustration of two photographs. Drying rate of white fir by segregation Item Preview remove-circlePages: raised the problem of how best to kiln-dry white fir and associated species in the minimum time while main-taining the maximum value by reducing drying de-grade and improving the uniformity of final moisture content of the kiln dried lumber.

The most serious problem in kiln-drying white fir to a uniform final moisture content is the segregation.

Description The segregation of white fir for kiln drying EPUB

to sort out kiln dried boards with greater than 19% MC and redry them in a later kiln run, but the redry operation increases kiln drying costs by at least 45%. Reinking reported 13 to 19% of kiln dried white fir lumber had to be redried regardless of the kiln schedule used (19).

Presorting or segregation of wetwood boards from normal. The Segregation of White Fir for Kiln Drying Smith, Harvey H.; John R.

Dittman Drying Rate of White Fir by Segregations Robinson, Lewis H. An Evaluation of Three Seasons of Anti-Lightning Operations in California.

important because an improved drying system can only evolve after a careful evaluation of the present overall operation has been made. Experimental Evaluation of Kiln Operations The first part of this phase was an analysis of segregation prac-tices as they relate to drying uniformity, drying. Example 2: To find the schedule for eastern white pine for use as furniture stock: Step 1–As furniture stock requires close control of final MC, look in the Index of Schedules for Kiln-Drying U.S.

and Canadian Softwood Species at Conventional Temperatures-A. Moisture Content-Controlled Schedules, page Find “pine, eastern white. Western hemlock is a dominant coastal species in British Columbia, Canada.

This species is commonly marketed with amabilis fir as Pacific Coast Hemlock or hem-fir. Hem-fir is difficult to dry, mostly because of the existence of wetwood and large initial moisture content variation.

The dried lumber will likely end up with a large final moisture content difference resulting in increased drying. Western white Redwood Spruce, Sitka Spruce, Engelmann aE L may be approximated by increasing modulus of elasticity values in Table 4–3 by 10%.

Just a quick clarification on "hem-fir". Hem-fir is hemlock that supposedly has the same structural characteristics as Douglas Fir. It is primarily logged from Washington state (where I live) and is generally about 10% cheaper than doug fir. As to the white wood, I have never seen hem-fir used as white.

Hem-Fir is a species combination of Western Hemlock and the true firs (Noble, California Red, Grand, Pacific Silver and White fir).With strength properties slightly below Douglas Fir-Larch, this is an extremely versatile species group and useful for multiple, general-purpose framing applications.

Arganbright, D. The segregation of green lumber for optimization of drying. Proceedings IUFRO Division 5 Meeting (Rep. of South Africa)2: 13–20 Google Scholar. When lumber companies kiln dry their wood, they do so in a controlled environment using carefully monitored temperature and humidity levels in order to avoid over-drying or under-drying.

This is critical because it allows the wood to dry to the correct MC for its ultimate intended use, thereby enabling the wood to maintain stability and dimension.

A kiln schedule, which indicates the desired temperature, humidity, and velocity in the dryer depending on the MC of the lumber, is a carefully worked-out compromise between the need to dry.

For all kiln drying schedules, a heater should be used to sterilize the lumber and kill any insects that may be present.

For a kiln temperature of ˚ F, sterilization takes three to five hours. With a ˚ F kiln temperature, sterilization will take 10 to 12 hours (Dry Kiln Operators Manual, ). These figures hold true for lumber up to 2. If I run low on firewood, I search my woods for these dead and barkless Elm trees to cut and burn without drying.

Note *3 Oak: I try to let my White Oak air dry for two years if possible. GREAT burning firewood but it must be air dried before burning. White Oak. No white fir mills are large enough to attain this level just from dry kilns alone, operated at conventional temperatures; however, at the higher temperature, a mill producing[3] ( million board feet [MMBF]) of lumber per year could reach that level of VOC emissions.

Robert McGuffy has headed up the wood-drying sequence at the Anderson-Tully Company's Vicksburg, Mississippi, hardwood-processing facility for decades. At this complex, the largest of its kind in the U.S., Robert has the responsibility for air-drying, and then kiln-drying, about 70 million board feet of hardwood every year.

This study aimed to investigate the changes of internal moisture content distributions of high-value hem-fir timbers after kiln drying while exposed to two different local outdoors seasonal conditions for a period of time of few weeks. Hem-fir is the most abundant species in coastal British Columbia, Canada, and high-quality thick hem-fir timbers used as construction material are one of the.

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The only reason for kiln drying lumber is to get it to market as a useable product faster. In home construction and most furniture, these internal flaws and stresses aren't a big issue, but in boat building that can be a real problem. There was a time when the kiln operator was a careful man, constantly managing his load and monitoring the gauges.

Sapwood nearly white, up to 3 inches wide in open-grown trees. Normally straight-grained. Easily worked, stable in use. Heavy, hard, strong, stiff. Good resistance to shock. High decay resistance. Approximate R-value per inch: Not available. Suitability: Difficult to pressure-treat. Expensive to kiln-dry.

A kiln is essentially like an oven. Large fans within the kiln move air that is heated through the kiln.

A kiln operator also can add or remove moisture from the kiln to insure that each piece of lumber is drying at a similar rate. At the end of this process, lumber will be between % moisture content, and referred to as kiln dried.

The heat of kiln drying makes lignin less susceptible to softening by steaming. Use kiln-dried lumber only for gentle bends. Six steps to better bending 1. Choose a wood species.

All temperate-zone hardwoods (chart below) steam-bend well and, in general, bend better than softwoods. Steam-bending other temperate-zone species is possible, but. Quality Drying of S-P-F for Dimension Lumber and Other End Uses Conventional & High-Temperature Spruce-Pine-Fir Kiln Operator Course This course will provide a thorough review of the basic principles involved in lumber drying.

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The course will progress from a presentation of the fundamentals of wood drying to the day-to-day operation of a dry kiln. Kiln Dried A great example of when to use kiln dried wood, besides the obvious framing lumber, is when you are installing a cedar deck.

Kiln drying is a common industry practice that ensures the lumber you buy is not only straight and free of splits. With a small-scale kiln, matched charges of wood, and careful measurement, methanol emissions varied over a range of 60 percent of the mean for southern pine (not sorted to matched charges), 46 percent for ponderosa pine, 42 percent for white fir, 16 percent for lodgepole pine, and 6 percent for Douglas-fir.

For ages, the finest builders, carpenters and craftsman alike have relied on Douglas Fir for its superior strength, exceptional work-ability and overall attractive appearance. Our Kiln Dried Timbers are dried and handled with the same care and attention to quality as all our specialty products.

Controlled drying in a kiln, especially when drying from the green state, reduces or eliminates splitting and checking. When lumber is air dried, however, there is no control over the drying process, and the weather can easily cause splitting and checking that results in losses.

SD19 means shipped dry 19% (plus or minus the 2% allowance) KD 19 means Kild dried 19% moisture Whew. the differance between saturation and moisture levels would fill up at least a chapter of a book, would you like me to recommend a book or two for you to read.

Tauton press publishes several like, Wood and how to dry it. Wetwood is more difficult to dry than normal wood and requires more energy.

Wood dries unevenly and may warp and twist. During kiln drying, acid vapors may cause kiln corrosion. It is associated with ring shake and honeycomb, two lumber defects. Ring shake.

White Fir OSU Kiln. Kiln drying is a superior drying method due to the high-temperature oven. Kiln dried wood is cleaner, safer, and more long-lasting than any other type. We kiln dry all of our firewood 12 times longer than the USDA standard, so you know you’re always getting the best.

The wood is cut correctly: When a piece of wood is cut evenly, it burns evenly. The tested source is a lumber dry kiln. Lumber destined for the mill’s kiln was sampled and tested in a small-scale kiln at Oregon State University.

Mill personnel reported that the logs came from Weyerhaeuser’s Vail tree farm approximately 30 miles east of Chehalis. The harvest was done in early January.

Sawing occurred on January 9,   Hello Im planing on building a good size full scribe round log house, with saddle noch for my family. Iv just been waiting on a site. We have 18 to 20 inch white cedar logs some even bigger at stump end.I was wondering when the best time of the year to cut these amazing trees and how long do i have to wait for them to be dry enough,before i start with the walls.