Shop work

Industrial and vocational texts being a series of text-books designed for use in the elementary and secondary schools, colleges and academies offering courses of instruction in the trades, crafts, wage-earning pursuits and home economics.

This book is the outgrowth of eighteen years of teaching in high schools and many more spent in practical construction work, in wood and iron, before our affiliation with industrial school work began. It consists of a compilation of such notes and lectures as we believe are important to the wood-worker. It is not intended in any way to supplant any of the work at the bench, but is designed to be used in connection with bench work to enable the student to approach his work more intelligently. The book is not designed as a self-instructor, but as a student's text to be used by the teacher, just as he would use a text in mathematics. To secure the best results in the use of any text, supplementary work must be done, and wood-working is no exception to the rule.

The work presented in this text is so designed as to require two years, working two hours per day, in its completion, and is intended as a ready reference for the pupil and the teacher. It will be observed that in this text cabinet-making follows joinery. It is not necessary that cabinet work should be taken before carpentry. If the student so desires, he may take either cabinet-making or carpentry or both, after he has finished joinery. All joint exercises should be worked out by the teacher in class demonstrations. The following brief, synoptical analysis may be of service to the teacher in the development of the subject as a whole.

Part I deals exclusively with the tools used in manual training shops, and with illustrations relative to the correct positions. Chapter III, Development of a Project, is worthy of careful analysis, since it indicates a general method of approach and order of work, and since the constructive work involves the use of so many methods. Care must be taken that too many tools are not presented to the pupil at once. Do not take up the use of a new tool for the sake of the tool but for the sake of the exercise which calls for the use of that particular tool.

Part II outlines a course in bench work, beginning with a series of joints which are standard the world over. Just how many joints the pupil shall make is a matter the teacher himself must determine. They are arranged in an order such that there is a gradual rise from the simpler to the more difficult and complex joints. This continuity should be followed in the presentation. In this series of joints, the fundamentals of all joint construction, whether they are in cabinet-making, in common carpentry, or in bridge building, will be found. The extended list of suggested projects for construction Should prove of great value to the instructor. Just enough is presented on each project to start the student in its development.

Part III consists of a series of talks which cover a wide field in practical tool usage, and which present many other things of vital importance to the artisan. It gives information which may be applied daily by the mechanic. These talks should be taken up, not necessarily in the order given, but in the order best suited to the teacher's own course. For example, a demonstration is given on how to sharpen a plane iron. It would naturally follow that this would be the proper time to present the talk on "Abrasives" ; or if the first lesson on sandpapering is before the class, the talk on "Sandpaper" should be given.

Part IV deals with miscellaneous topics as applied to shop work. The questions should be given in class, in oral recitations, so that each pupil may familarize himself with the technical terms. The problems may be assigned for work outside of recitation, and others may be substituted to embody certain features of the pupil's own exercise under construction. The glossary is intended for the use of those who are not familiar with certain technical terms and phrases.

It is the belief of the authors that the working drawings, lectures, tool references, constructive information, suggested projects, questions and problems amply justify the publication of this book. If the book shall prove to be of material assistance in the unification of a course of study, embodying both practical and cultural training, it will have served its purpose. While we believe that the cultural side of industrial work should not be overlooked, yet "the search-light of practical experience should illuminate the dark places of theory".

Woodworking Machinery. - For the rapid shaping and reproduction of similar forms, woodworking machinery is used. Machines designed for practically all classes of work are on the market, and new machines, as well as improvements on the old, are developed readily. Probably the most common machines used in industrial schools are the following:

Saw bench with ripsaw and cross-cut saw;
Band saw;
Surfacer;
Hand planer and jointer;
Speed lathes;
Trimmer;
Tool grinder.

These machines vary in form and size and in their equipment with special parts best suited for diversified kinds of work.

Universal Saw Bench. - The rip saw is indispensable in a modern school shop. The accompanying cut (Fig. 100) shows a modern saw bench which can be fitted up with attachments for many classes of special work. The base is cast in one piece, making the machine rigid. The table, which is provided with a tilting mechanism, and is operated by hand, and which has a stationary and rolling section, is also made of metal. This machine is provided with a yoke, having two arbors, on which the saws are mounted and revolved by a hand wheel, engaging worm and gear. The latter is protected by a dust-proof casing. The saw can be fitted with either direct motor or countershaft drive. The equipment consists of a rip saw, a cross-cut saw, a universal ripping fence, a miter cut-off gauge, a universal miter gauge, and a clearance block.


Band Saw. - The band saw is a piece of woodworking machinery, consisting of a steel band, from whence the name is derived, which runs over two wheels in the same manner as a belt. It is used in pattern shops, saw mills, planing mills, and in wood novelty shops. It is used extensively for sawing curves, ripping, and sawing irregular work in general. With the band saw blade in motion, the wood is fed to it. The operator slides the wood over a table, which can be tilted to any angle, thus making it easy to hold and guide the piece of wood.

Band saw blades are made in all widths, and in lengths suitable for the capacity of the machine. By capacity is meant the working clearance under the guide and between the blade and column. (See Fig. 101.)

Surfacer. - The surfacer is a machine which is used extensively by cabinet makers, pattern makers, and manufacturers of pianos, organs, vehicles, cars, doors, sashes, boats, blinds, and wood novelties of all kinds, for planing or surfacing stock. It does, on a large scale, the same kind of work which may be done with smooth and jack planes. It is a great time saver. The frame of the surfacer is made of cored section sides, and heavy ribbed girts, machine jointed and bolted. The bed is raised and lowered by a hand wheel. The surfacer can be fitted with either direct motor or countershaft drive. The rough stock is fed through the machine by means of four rollers. The cylindrical head, which makes 5,000 revolutions per minute, cuts from beneath the surface, thus retaining the keen cutting edge longer. Experience has proved that the knives should be ground at an angle of 42 degrees in order to obtain the best results. (See Fig. 102.)

Hand Planer and Jointer. – The hand planer and jointer is used in all woodworking shops for dressing and joining wood. The head, or cylinder, with two knives inset, should make about 5,000 revolutions per minute in order to develop the maximum cutting efficiency. The cutting blades, like those of the surfacer, cut from underneath the face of the wood, thus making it possible to work over finished material. The knives should be shielded as much of the time as possible. For all joint work, the line of the take-off table should be tangent to the circle described by the revolving knives. (See Fig. 103.)

Lathes. - Lathes are used extensively in school and pattern making shops in doing cylindrical and spherical work. They are either motor or belt driven, and the drive must be so arranged as to give variable speeds.

A pattern maker's lathe is generally provided with a tool carriage, hand fed, which has a longitudinal and cross feed. All cylindrical and spherical work, with their variations, can be done on the lathe. The swing of the lathe is determined by the distance between the live center and the top of the bed, this being one-half the size of the stock worked. The distance between the centers determines the length of stock that can be worked. (See Fig. 104.)

Trimmer. - The wood trimmer is a tool used in all pattern, cabinet and novelty shops for trimming the ends of small pieces of wood. The cutting is done by knives. These knives are forced through the wood which is held against a stop at the correct angle.

The knives have a shearing motion which leaves a clean unbroken cut. The points of the knives should always be shielded, and only one person at a time should operate the wood trimmer. (See Fig. 105.)

Oilstone Tool Edge Grinder. - A tool grinder is indispensable in any shop, no matter whether natural or artificial stones are used. However, artificial stones must be used with the knife grinding attachment. Grinders with two wheels, one of medium and one of fine grit, are most desirable.

New wheels should be thoroughly soaked with kerosene before using and a little added from time to time. They readily absorb the oil and will appear to be dry when not running, but the centrifugal force will bring the oil to the face of the wheel when the proper speed is reached. (See Fig. 106.)