Lathe Operations: Facing

Facing Operations Facing is the process of removing metal from the end of a workpiece to produce a flat surface. Most often, the workpiece is cylindrical, but using a 4-jaw chuck you can face rectangular or odd-shaped work to form cubes and other non-cylindrical shapes.

When a lathe cutting tool removes metal it applies considerable tangential (i.e. lateral or sideways) force to the workpiece. To safely perform a facing operation the end of the workpiece must be positioned close to the jaws of the chuck. The workpiece should not extend more than 2-3 times its diameter from the chuck jaws unless a steady rest is used to support the free end. Cutting Speeds

If you read many books on machining you will find a lot of information about the correct cutting speed for the movement of the cutting tool in relation to the workpiece. You must consider the rotational speed of the workpiece and the movement of the tool relative to the workpiece. Basically, the softer the metal the faster the cutting. D…

How to develop wood turning skill?

In the case of woodturning there is a bit more to it than motor skills because, with the right attitude of mind, it is within the power of the individual to alter the shape of the learning curve. The key to skill is attitude. What does this mean? To begin with it means developing an understanding of the correct basic techniques. If the turner does not get the basics right then, however much he practises, he will not improve. In contrast he may develop a lot of bad practices which will be difficult to eradicate.

It is necessary to have a strong desire to learn and progress but at the same time one must have patience. It is no use the turner trying to make things which are way beyond his level ability, particularly in the early stages. On the other hand it is necessary for him to stretch himself with projects of steadily increasing difficulty. It may be a good idea for the learner to set himself a series of achievable goals.

Nevertheless, it has to be recognised that the hobby turner with only limited time at his disposal is in a different position to the aspiring professional. Learning to turn is like learning to play a musical instrument (although turning is far less difficult). Regular short periods of practice are preferable to periods of intensive effort with big gaps between them. Having said that it must be acknowledged that the hobbyist will have to fit his turning into the free time he has available and do the best he can. Life is full of compromises, and this is one of them.

In developing skills and working out the best way to progress it will be necessary to experiment with the various cuts, tools and techniques. In order to avoid dangerous practices, some caution is required in doing this, but experimentation is a very necessary part of the learning process. However, in the early stages the instructions given in the following chapters should be followed with care.

Whatever his circumstances, and however much time he has available, when the aspiring turner is practising he must keep thinking about what he is doing and asking himself questions. When things go wrong he must ask himself: why? What happened? What can I do to try to ensure it does not happen again? It also helps if the turner can recognise when things are going right, so that he will know what things he can do, as well as those he cannot.

Good turning entails careful observation involving the three main senses: sight, sound, and touch. The eyes are the primary source of information. Obviously, it is necessary to look to see what one is doing, but one should also be watching for the results. What is happening to the shape: is it smooth or is it ridged? Will I be able to blend it into the profile I want? Are the fibres tearing? What else can I see?

Sound provides further important information so it is necessary to keep one's ears open. For example, when a cut is being made correctly there will be a variety of sounds but underneath these it should be possible to hear a relatively quiet, but clearly distinguishable, hiss which is made by the fibres being cut cleanly. The other sounds carry information as well. When I am teaching more than one person at a time I can often tell when someone is having trouble from the sound alone.

Yet more vital information is being transmitted back to the turner through the tool. The turner should try to develop as much sensitivity in the hands as he can, holding the tool as lightly as possible. Even where a firmer grip is required the turner can still feel what is happening as well as see or hear.

In many cases where a cut is not going correctly all three senses will be telling the turner that something is wrong. In other cases just one will be enough. For example, when a hidden split, or other defect, in the wood is encountered there is often a quiet click which warns the turner to stop the lathe to have a look.

In summary, therefore, it can be said that these three senses are providing the turner with a stream of information which has to be continually interpreted. Much of the time, it is to be hoped, the signal will be that all is well, but the turner must be vigilant. By applying himself diligently to the task, developing a sensitivity to the stream of information, continually analysing his actions and their results, and practising as regularly as possible the turner can learn more quickly and will eventually reach a higher level of skill.


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