Small Sawmill Operator's Manual

01452 SMAL SAWMILi; OPERATOR MANUAL 5">>i~» J* Agriculture Handbook No. 27 n?' IE î^ U. S. DEPARTMENT OF AGRICULTURE FOREST SERVICE Agriculture Handbook No. 27 January 1952 Approved for reprinting July 1958 SMALL SAWMILL OPERATOR'S MANUAL By C. J. TELFORD, Small Sawmill Specialist Forest Products Laboratory, Branch of Research, Forest Service UNITED STATES DEPARTMENT OF AGRICULTURE, WASHINGTON, D. C. For sale by the Superintendent of Documents, Washington, D. C. Price 65 cents ACKNOWLEDGMENT Acknowledgment is made of the assistance given by the following indi- viduals and firms in the form of technical data, advice, and many of the photographs and drawings which appear in this manual: American Sawmill Machin- ery Co., Hackettstown, N. J. ; Andrus Manufacturers, Eugene, Oreg. ; Atkins, E; C, and Co., Cincinnati, Ohio ; Bowden, J. E., Alpha, Oreg. ; Chattanooga Saw Works, Chattanooga, Tenn.; Churchill, George, Drain, Oreg.; Corinth Machinery Co., Corinth, Miss.; Corley Manufacturing Co., Chattanooga, Tenn. Crabb Gas Engine Co., Independence, la.; Disston, Henry, Sons Inc., Phil- adelphia, Pa.; Enterprise Co., Columbiana, Ohio; Forano Co., Ltd., Plessisville, Quebec, Canada ; Farquhar, A. B., Co., Ltd., York, Pa. ; Fisher-Davis Co., St. Louis, Mo. ; Foshee, H. B., Jacksonville, Fla. ; Frick Co., Waynesboro, Pa. ; Fug- lie, E. A., Winona, Minn.; Gordon Hollow Blast Grate Co., Greenville, Mich.; Hallock, Hiram, Madison, Wis. ; Hanchett Co., Big Rapids, Mich. ; Hart Bros. Machinery Co., Clarksburg, W. Va. ; Hoe, R., and Co., Inc., New York, N. Y. ; Howell R. R., and Co., Minneapohs, Minn. ; Ireland Mill and Supply Co., Cayuta, N. Y. ; Jackson Box Co., Black River Falls, Wis. ; Jackson Harvester, Inc., Brew- ton, Ala. Lane Manufacturing Co., Montpelier, Vt. ; Mater Machinery Corp., Corval- lis, Oreg. ; Mill Engineering and Supply Co., Seattle, Wash. ; Olsen, Leslie, Mora, Minn. ; Peters Co., Portland, Oreg. ; Sawmill Equipment Co., Inc., Kelso, Wash. ; Simonds Saw and Steel Co., Fitchburg, Mass. ; Sinker Davis Co., Indianapolis, Ind. ; Sumner Iron Works, Everett, Wash. ; Topping, Floyd, Wild Rose, Wis. ; Wheland Co., Chattanooga, Tenn. C.'. ^^^'à^i\OtQ\. n TABLE OF CONTENTS Pace Page Introduction . 1 Care and maintenance of saws—Continued Purpose and scope 1 Filing circular ripsaws 56 Safety measures 1 Filing circular crosscut saws 58 Types of small sawmill headrigs 2 Labor requirements for small sawmills 59 Sash-gang headsaws 2 Work distribution by crew size 60 Band headsaws 3 Mill layout 61 Circular headsaws 3 Log yards and ponds 61 Sizes of headrigs 4 Lumber yard layout 63 Husk and mandrel 7 Piling and sorting lumber for air drying ... 64 Headsaw guides 9 Dipping tanks 71 Rolls and spreaders 9 End coatings 71 Peed works 9 Sample plans of mill layouts 73 Carriages and trackways 14 Setting up an unsheltered ground mill accord- Setworks and receders 15 ing to plan 1 73 Dogs , 21 Building plan and machine location for shel- Edgars 25 tered portable mill according to plan 2 . 75 Trim and cut-off saws 26 Building plan and machine location for semi- Log turners 30 permanent tie mill according to plan 3 . 77 Metal detectors 33 Building plan and machine location for semi- Conveyor systems 34 permanent lumber mill according to plan 4 79 Sawdust chains 34 Building plan and machine location for perma- Sawdust blowers 34 nent heavy mill according to plan 5 79 Dead rolls 35 Load-out equipment 83 Live rolls 35 Car and trackway 83 Belt conveyors 36 Lumber props 83 Chain conveyors 37 Rolls 83 Trash-disposal systems and methods 37 Loading scaffolds 84 Power and transmission equipment 39 Sliding skids 84 Horsepower requirements 39 Trucks and rails 86 Classification of prime movers by types .... 41 Pork-lift trucks 89 Basis of horsepower ratings 41 Mill operation 89 Comparison of types of prime movers 42 Milling softwood logs 89 Variants of each type of prime mover 42 Milling hardwood logs 91 , Dutch-oven furnaces for burning sawdust ... 42 Sawing oversized logs 97 Belts and pulleys 44 Size standards 98 Flat belts 44 Tallying and grading 102 V-belts 45 Some business aspects of small-mill operation . 103 Transmission capacity of belts 45 Capital requirements 105 Pulleys 47 Marketing 105 Shafts and bearings 48 Accounting 106 Care and maintenance of saws 48 Public regulations affecting sawmills 110 Sawteeth 49 Scaling and grading logs Ill Factors affecting selection and operation of Log scaling Ill saws 50 Log grading 112 Saw speed and chip thickness 51 Organizations issuing grading rules 113 Tensioning the saw 52 Glossary 114 Alinement of saw and teeth 55 Index 119 III INTRODUCTION Small sawmills are an integral part of our 3,000 to 300,000 board feet in 8-hour produc- lumber-manufacturing industry. No important tion capacity. For purposes of this bulletin, lumber-producing region of the United States mills producing up to 20,000 board feet per 8- is without them. They perform several essen- hour shift have been classified as small. This tial functions, not the least of which is the dividing line is low for certain west coast mills ; economical production of lumber under con- but elsewhere in the United States, the ma- ditions that make it impractical to operate large jority of the mills operating today fall well mills. With small capital investment and low within this limitation. operating costs, they can supply local needs from locally grown timber ; yet they contribute Purpose and Scope importantly to the lumber supplies of metro- politan areas. They also fill an economic need This publication is intended to serve as a in regions where large mills nourish, serving handbook for operators of small mills. It deals as auxiliaries that utilize timber of sizes and mainly with the types and variations of equip- kinds not suitable for the large mills. ment available, installation of equipment, and The need for improvement in small sawmill operational techniques, especially for mills of operation has long been recognized. At the the circular head-saw type. The purpose is to request of the Chief Forester in 1926, a unit furnish operators with a reasonably complete was set up at the Forest Products Laboratory and detailed evaulation of various types of to investigate means of improving the operat- machinery and handling equipment, so that the ing efliciency of small sawmills, particularly general standard of operation may be raised by those operating on the National Forests and reducing costs, preventing wastes, and improv- farm woodlands. As part of its program, this ing the quality of the lumber. unit has assisted extension agencies in con- Although logging is ordinarily an insepar- ducting schools for sawmill operators and has able part of small-mill operations, it is not published recommended practices for definite covered in this handbook. Brief treatment is phases of small-mill operation. In order to given such important segments of mill manage- stimulate lumber production during World War ment policy as buying and selling; inventories II, a short bulletin (U. S. Department of Agri- of timber, logs, and lumber; selection of sales culture Misc. Pub. 509) was published for outlets, and extension of credits. guidance of small-mill operators. The present manual is an amplification of that bulletin and Safety Measures other publications issued as a part of this program. Although outside the scope of this publication, reducing the hazards in sawing and Many different types of sawmill equipment machining lumber is one of the most important are described and illustrated in this manual, in steps in sawmill operation. Statistics clearly order to provide operators with a reference show that sawmilling is one of the most haz- source as an aid in selection, as well as to por- ardous occupations. Familiarity and compliance tray mechanical principles controlling the func- with State regulations and with responsibilities tioning of parts as an aid in correcting faulty under workmen's compensation acts are essen- mechanisms, and to provide guidance in the tial in sawmill design and management. This construction of certain items which can be publication does not attempt to deal with spe- made by or for the individual operator. Per- cific safety measures because sawmill safety is mission has been given by manufacturers for a subject in itself and requires fuller treatment the use of photographs of certain sawmill than can be given here. Other publications features which are undoubtedly protected by must be relied upon for detailed information on patent rights. The reader should be aware that safety measures. publication in this manual does not constitute Some of the literature on safety provisions a justification for copying features so as to in sawmill operation consists of the Logging infringe on patent rights in any manner. and Sawmill Safety Code, National Bureau of There is no hard-and-fast rule differentiating Standards Handbook No. 5, and special subject "small" from "medium" and "large" mills. matter that can be procured through the Sawmills of the United States range from National Safety Council, Chicago, 111. TYPES OF SMALL SAWMILL HEADRIGS For the purposes of this manual small saw- product costs. The objectives sought for head- mills are classified according to the type of saw equipment may be listed as (1) maximum headsaw employed. There are three distinct recovery of lumber from the log, (2) recovery types of sawmill headsaws, circular, sash-gang, of maximum qualities on a grade and thick- and band. Variations of the circular-headsaw ness basis, (3) accurate sizing, and (4) min- type are the single-circular with or without a imum labor and machine costs per thousand circular top saw; the twin-circular; and the board feet. None of the three general types of gang-circular. All are used in small mills, but headrigs excels in attaining all four objectives. numerically the single-circular dominates al- most to the exclusion of the others.

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