Lathe: Work Centering The Mechanic Resume
Lathe: Work Centering The Mechanic Training

(17) 17 product ratings - 7' x 14' Mini Metal Lathe 550W Precision Variable Speed 2250 RPM 0.75HP. VERY NICE CONDITION ORIG SOUTH BEND 9 10K LATHE 4' BED QUICK CHANGE LEAD SCREW. $46.70 shipping. Logan Lathe 5C Collet Spindle Adapter # 1055-1, 2 1/2” L, 1 5/16” Dia., See Desc. Then mount the work between the live and dead centers of the lathe. CENTERING THE WORK.—To center round stock where the ends are to be turned and must be concentric with the unturned body, mount the work on the head spindle in a universal chuck or a draw-in collet chuck If the work is long and too large to pass through the spindle, use a. It is used to make threads of required length and depth on a work piece. It is done by fixing tool perpendicular to the axis of work piece and by giving automatic feed at low speed. Boring: The process in which material is removed from the inside of work piece is called BORING. It is used to enlarge the inner diameter of the hole. A wide variety of central machinery wood lathe chucks options are available to you, such as 3, 4. There are 91 suppliers who sells central machinery wood lathe chucks on Alibaba.com, mainly located in Asia. The top countries of supplier is China, from which the percentage of central machinery wood lathe chucks supply is 100% respectively. Mar 24, 2017 Work Held Between Centre 10. Work Held Between Centres 11. Face plate. A faceplate is the basic workholding accessory for a lathe. It is a circular metal plate which fixes to the end of the lathe spindle.

Lathe: Work Centering The Mechanic Resume

Description

This section is from the book 'Machine Shop Work', by Frederick W. Turner, Oscar E. Perrigo, Howard P. Fairfield. Also available from Amazon: Machine shop work.

A piece to be turned is supported on the two centers of the lathe. In order that this may be done, it is prepared by drilling and countersinking a hole in each end. This is called centering the work. The countersunk hole should have the same angle as the lathe center upon which it is to run. The hole should be drilled deep enough so that the point of the lathe center may not strike. The shape of the hole is shown in Fig. 133. The generally accepted standard angle is 60 degrees. The effect of using a 60-degree hole on a 90-degree center is shown in Fig. 134. The result of such an application is that the bearing will be concentrated on a line AB, causing rapid wear of the outer end of the hole, and a cutting of the dead center. Driver programming softwarewillbrown.

Fig. 133. Hole and Center of Correct • Angle for Centering Work.

Lathe: work centering the mechanic training

Fig. 134. Effect of Using Different Angled Hole and Center.

The size of center holes varies with the weight of the work and the character of the operation. Heavy work and rough turning require large center holes, while small work and fine turning can be done without countersinking deeply. As bearing surfaces in cast iron must be large to be satisfactory, center holes in cast iron are likely to give trouble by unequal and rapid wear. When heavy turned work in cast iron must be very accurate, it is well to drill a hole in each end, drive in a plug of Wrought iron or mild steel, and form the center holes in the plugs thus driven.

When the piece to be turned has been put in place, the dead center should be oiled and screwed up into position. It should be tightened so that there is no lost motion, and yet allow the work to rotate freely.

Chuck Method

The turning of shafts and bars is not, however, the only kind of work to be done on a lathe. Pieces can be turned that are thin, that have holes through the center, or which are so shaped that they cannot be held upon the centers. In such cases it becomes necessary to hold the work firmly without distortion. This may be done by use of the lathe chuck.

Fig. 135. Work Clamped to Faceplate.

Faceplate Method

Lathe: Work Centering The Mechanic Training

Still another method of holding a piece to be worked is that shown in Fig. 135. The piece is clamped to the faceplate. When this is done, there should be a bearing on the faceplate immediately beneath the clamping strap. For example, consider Fig. 136. Suppose a disc having four feet on one side is to be faced off on the front. The clamps should be placed directly over the feet, as in B. If they are placed between the feet at EE, the work will be sprung out of shape, as shown by the dotted lines in A. Then, when the tool has done its work, the shape of the piece, while bolted to the faceplate, will be as shown in C. As soon as the pressure of the straps is removed, the elasticity of the metal will cause the piece to assume the convex form shown in D; whereas, if the straps had been placed as shown in B, no distortion would have been produced.

Fig. 136. Proper and Improper Method of Clamping Work.

An angle iron may be clamped on a faceplate, as shown in Fig. 137, presenting a surface parallel to the lathe axis, to which work may be attached. The angle irons may, of course, be at any angle to the faceplate, but 90 degrees is the one most commonly used. When work is held in this manner, it is desirable to counterbalance it, as is also shown in Fig. 137,

Fig. 137. Angle Iron Clamped to Faceplate and Counterbalanced.

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Lathe: Work Centeringthe Mechanic