INTRODUCTION TO WOODTURNING
Chapter 5: Safety
We are getting near the point when we can put a piece of wood in the lathe, switch on and start practising. But before we do that there are a number of important points regarding safety which need to be considered. It should be noted, however, that serious accidents from woodturning activities are relatively rare. Nonetheless, very few human activities are completely risk free and it is sensible to obtain as complete an understanding as possible of where possible dangers may lie in woodturning. What we need to be concerned with principally are those accidents which can cause serious hurt or disablement. In the following I will look at those areas where there is potential danger.
The danger with clothing lies in the possibility that it might be caught in the lathe or the work-piece at it revolves. As a consequence all clothing should be relatively tight fitting. Ties should not be worn, and there should be no loose cuffs, or anything of a similar nature, which might get caught up. Unless watches are covered by clothing they should be removed, as should rings, necklaces and other items of jewellery. There is also the possibility of injury to the feet. Since I dropped a large bowl blank on my toes I have thought it a good idea to wear safety shoes. Sandals and even trainers are inadvisable.
Long hair should be kept carefully under control when near any machinery. I have never heard of it happening to a woodturner but in engineering workshops people have been scalped because their hair has been caught in machinery.
Some sort of protection for the eyes is desirable, at the very least safety glasses should be worn. As I normally wear glasses with plastic lenses I tend to rely on these under most circumstance. However, if, when turning, I think there is particular danger of a loose piece of wood or bark flying off I put on a full face mask. As an extra precaution I also stand out of the firing line. Eye protection is also very necessary when using the grinder. There is always a possibility that a fragment of metal or other debris may be flung off the wheel. This is particularly likely when dressing the wheel.
5.5 Wood dust and toxicity
Wood dust, particularly fine dust, is an almost invisible but insidious hazard. Long-term exposure to wood dust can have effects on the eyes, nose, throat, lungs and skin. Effects on the eyes include: soreness, watering and conjunctivitis. Those on the nose include: rhinitis (runny nose), violent sneezing, blockage and (very rarely) nasal cancer. The effects on the lungs include: breathing difficulties, impairment of lung function and the triggering of asthma attacks. There have been instances where the inhalation of wood dust has had whole body effects such as headache, thirst, nausea, visual disturbance, drowsiness, anaemia and hepatitis.
The long-term effects are likely to concern only professional turners who have been working at the craft for a relatively long period. Nevertheless, some of the effects described above, such sneezing, can occur after short-term exposure. I have suffered from a sore throat and cold-like symptoms after a few days in the dusty conditions of a woodworking exhibition.
Relatively short exposure to wood dust, such as that which may be experienced by amateur turners, can also have irritant effects on the skin which can lead to nettle rashes or irritant dermatitis. Symptoms usually only persist as long as the affected skin site remains in contact with the dust. Similar, and more worrying effects, can result from the development of allergic dermatitis caused by contact with the dust of specific wood species. Asthma can also be caused as a similar specific allergic reaction. Once sensitised the skin or lungs may react severely if subsequently exposed even to very small amounts of dust from the specific species.
As far as woodturning is concerned wood dust is mostly produced by sanding, particularly power sanding, on the lathe, as well as by cutting wood on the band-saw. Dust is also raised by sweeping and cleaning-up. Any turner who wears glasses will know that when these operations are taking place the lenses quickly become covered in dust. This is what one is breathing unless precautions are taken.
The most dangerous dust is the finest dust. This fine dust is so light it will hang in the air for a long period after the activity which produced it has ceased. Ideally an efficient dust extraction system which will remove the smallest particles should be fitted. But many amateurs, and those who spend only a limited amount of time turning, will be not be able to justify such expense. In that case some form of dust mask, or a battery powered respirator, should be worn.
Protection against allergic reactions to wood dust is very difficult to achieve. Fortunately, for most of us, it is relatively uncommon. Those of us who have not suffered in this way should not be smug, however, because an allergy can strike without warning and once sensitised the victim will always remain allergic. There is a mitigating factor in that these allergies, as mentioned above, are specific to particular species. The answer for those who have become allergic to a species is to try to avoid using it.
Another possible danger from dust is that of fire or explosion. Explosions caused by wood dust are not unknown but I have never heard of them occurring in a woodturner's work shop. Where the latter is concerned, one place where high enough concentrations of dust might occur is within a dust extraction system, particularly if there are positions where dust might collect.
Fine dust gets everywhere in a work-shop including electrical fittings such as plugs and switches. It is conceivable that a spark might ignite such dust when it could smoulder for some time before bursting into flame. Fire and explosion from such causes are unlikely perhaps, but it is well to be aware of the possibility.
Noise can also create a long-term hazard. Persistent exposure to loud noise can result in deafness. Generally speaking, woodturning is not a noisy occupation, but there can be occasions when it and allied activities such as powered sawing, particularly with a chain-saw, can produce high sound levels. On such occasions it is a wise precaution to wear ear protection.
5.7 Physical fitness
There are some books on woodturning that advise one never to work when tired. This really is a counsel of perfection. Only in an ideal world would it be possible to follow that advice. The use of alcohol is another matter. Using any machinery after drinking should be avoided.
Guards, particularly those over pulleys on the lathe and on band-saws, are fitted not only to protect the operator from an absent minded action, or slip, but also to protect other people who may come into the work shop. They should be used.
Lathes are sometimes used in public places, such as craft fairs, where guards and safety screens are even more important. I have seen a lathe at a craft fair used with no guards over the pulleys and nothing to keep the public at a safe distance. That is irresponsible. I have also seen a turner at a craft fair wearing a face screen to protect himself but with no safety screen to protect the public. In such circumstances clear polycarbonate plastic safety screens should be fitted. Polycarbonate is very strong, in contrast acrylic is unsuitable because it can shatter under impact.
5.9 Turning speeds
If the turner is in any doubt about which speed to use the lower option should always be selected first. The danger from excessive speed is that the work-piece, or bits of it, may be flung from the lathe. The biggest danger is from a work-piece that is badly split or is built up from glued up pieces (such as stave work). I once had an extremely painful blow on the arm from a large oak platter which split into two pieces as I was taking a cut. I was lucky - a piece might have hit me in the face or some other vulnerable area. I have also heard more than one story about the disintegration of built-up work. Where any danger of such mishaps is perceived a low speed should be selected.
Quite frequently pieces of scrap wood are glued to the work-piece as a means of mounting it on a face plate, or chuck, to prevent screw marks appearing in the finished piece. It is tempting to use plywood or MDF (medium density fibreboard) for this purpose. This should be avoided if the work-piece is of any size. Both of these materials tend to be very weak across the layers and may split under load. The use of paper in the glue joint is often recommended for the reason that it makes it easier to separate the waste piece from the finished work. For that very reason this technique should be used only be on relatively small jobs.
5.10 Checking the work-piece
When starting a new piece of spindle turning care should be taken to ensure that the work-piece is held firmly. Subsequently, the work-piece should be checked from time to time to make sure that it has not worked loose.
5.11 Adjustment of the tool rest
Whenever a new work-piece is fitted to the lathe it should be rotated by hand before switching on to ensure that any projections will not catch on the tool rest. Whenever adjustments are to be made to the tool rest the lathe should be switched off. Before switching the lathe back on the work-piece should again be rotated by hand.
A possible source of danger to the hands is the use of cloth for polishing. When a piece of rag is used, particularly a piece with loose strands where it has been torn, it can get caught in the rough wood where the work-piece has been partially parted off. When this happens the cloth is wrapped tightly around the wood in a fraction of a second. Consequently, when cloth is used, it should be held loosely in the hand so that if it is caught it will pull out easily. It should definitely not be wrapped around the hand. It is best not to use cloth at all, many turners now use paper towel for applying finish and polishing. It is readily available, cheap and, above all, safe. If it does catch on the wood it just tears.
5.13 Precautions against a dig-in
Fear, and the muscular tension which accompanies it, can inhibit the novice turner. If the beginner is very afraid of a dig-in, and what happen as a consequence, he can make arrangements for the drive to slip (like a clutch) if unusual resistance is encountered. On some lathes it is possible to run the lathe with a loose belt. Where this is not possible the work-piece can be driven with a solid cone centre or ring centre. In this case a rotating centre must be used at the tailstock end. Either of these arrangements will permit the drive to slip if there is extra resistance.
5.14 Use of the correct tools
It should become clear from the instructions which follow in subsequent sections of this book that successful turning will only result from the use of the right tools for the job. There some instances, however, the use of the wrong tools, or the right tools in the wrong way, can be dangerous. The instructions given should be followed with care.
5.15 The use of other machinery
This is not the place to comment on the safe use of all the additional machinery which might be used by the wood turner. There are, however, three machines which can be considered, two of which are very commonly used, ie the grinder and the band-saw, and one which is used from time to time which is potentially extremely dangerous. The main safety precautions to be taken in relation to the grinder are covered in Chapter 4 and should be referred to there.
I am not qualified to comment on all the safety precautions which should be taken with a band-saw. Nonetheless, there are a number of things I have become aware of through experience. Full use should be made of the safety guard. This should always be brought down as close to the work as possible. Like a grinder the a band-saw will continue to run after it has been switched off. Consequently, after completing a cut I make a practice of pulling the guard down to table level. Obviously the fingers should be kept as far away from the blade as possible, push sticks are a must.
It is often necessary to cut pieces of wood of an irregular shape. These can include burrs and limb wood. Because of lack of support under the blade the work can be caught by the teeth and given an sudden, uncontrollable, jerk. As a result the fingers could be brought into contact with the blade. Even if this does not happen the fingers can be injured by being caught under the work - I once lost a finger nail when this happened when I was attempting to cut a small log. Some means of safely supporting such pieces of work should be found.
The tool to be treated with the utmost respect is the chain saw. This is not the place to go into the safe use of this tool. Anyone preparing to use this tool should ensure that they are aware of all the hazards it presents, and that they make use of the appropriate safety measures and clothing.
5.16 A clear floor space
Fires do occur in work shops.They may not be a source of personal danger but they are a hazard which could result in damage to property and equipment. Particularly in timber work shops naked lights and inflammable materials should be handled with care. An eye should also be kept open for the possibility of electrical faults. Cloth or paper soaked in finishing materials such as cellulose or oil can ignite by means of spontaneous combustion if collected together in sufficient concentration. I make sure that each piece has thoroughly dried out before binning it.
This chapter turned out to be much longer than I expected when I began writing it. But I make no apology for labouring the point. Serious accidents to woodturners are uncommon and are no more likely to occur than accidents to people undertaking other relatively 'safe' activities. I used to know two people who had accidents playing table tennis; one broke his jaw and the other his ankle. If we were deterred from such activities because of the fear of an accident then we would not do anything and miss a lot of pleasure. Having said that, it should be acknowledged that the possibility of an accident can be greatly reduced by knowing where the dangers may lie. My two table tennis playing friends could have avoided some serious discomfiture if one had been aware of the danger of slipping on water on the floor and the other of a brick lying in the corner of the room.