Safety Devices

This is a topic I wanted to cover as part of the Safety Week 08 as a video, but I don’t have a good enough range of devices yet to really do the topic justice. So I’ll write a bit about it instead!

What I’m talking about here are on-tool safety devices, and onces that we use to improve our material handling (primarily keeping things we want to keep away from the cutters!)

There are a whole raft of devices: push sticks, holddowns, featherboards, splitters, riving knives, guards, anti-kickback pawls etc and so the list goes on.

There are two primary things all these safety devices are trying to achieve: keeping your bodyparts away from the cutting things and/or stopping the cutting thing throwing the material at you at very high speed.

Before I go on, there are some rules. (In fact it seems many of the rules and instructions provided with machines can be generalised into stopping the tool biting you, or incorrectly eating the material it is being fed. I guess the code violation of reading the instruction manual may have to be overlooked if you want to be safe!)

The rules are: no loose clothing, hair tied back (unless your haircuts are as short as mine!!), no jewelery, no rings, no gloves. There are lots of don’ts. If you look at the list, it can also be generalised. Don’t provide the machine anything that it can snag on and pull you into it. It happens a lot – don’t become a statistic.

The first category of devices are ones designed to stop you getting cut. These include pushsticks, machinery guards and techniques. The first two are obvious – keeping your hands away from the cutters so you can manipulate the workpiece from a distance, and blocks so if you do stray too close there is something there to impede you from getting to the cutter.

Techniques though? Perhaps not the best term, but I’ll explain what I mean. There are a number of things you can do to reduce the likelihood of an accident occurring. Keep the blades sharp (????!!!!!), keep the machine lubricated, especially the contact surface between the machine and the material, operate the machine at sufficient speed, don’t over-tighten the material holddowns (ie so they are not pushing too tightly onto the work). All these will achieve one thing – preventing you from being tempted into applying too much pressure when feeding the material into the tool. The more you push, the more likely you are to slip, and fall into the blade. On the other hand, the easier a piece of wood slides nicely into the tool and out the other side, the safer it is, the finer the finish, and the more enjoyable the whole woodworking experience. What would you prefer – having to fight to get the material in and through the machine, or have it glide on past?

Back to the other two – guards are obvious. Well, so are pushsticks, but they get avoided so often. I think the reason they are is because of that loss of feeling and control for you as the operator. If you are physically holding the material you can better control where it is going, and how hard it is to get it there. We recognise the need for a pushstick, but are concerned about loosing control of the workpiece. So get a better pushstick! And use some of the anti-kickback devices so the concern does not have to be there in the first place.

The basic pushsticks consist of a handle, and a small notch to push on the work. Sure they do that, but there is nothing stopping the workpiece skewing and getting caught (and thrown). They are also a point-contact, so for example the back of the blade of a tablesaw can start to cause the workpiece to lift (and potentially be thrown again).

As much as they keep the hands clear, they are a poor design. Pity so many of the commercial ones are just this type.

Instead, how about ones that not only feed the work into the device, but also hold the work down on the table?

This (from Taunton’s Fine Woodworking) is just one design, but you get the idea- it pushes from behind and still holds the work down.

Couple this up with some sort of featherboard, and the workpiece is controlled, unlikely to float (what I call it when the rear of the blade lifts the work up – it looks like it is floating on a jet of air), and pushed through with your hands clear of the blade.

You can also have featherboards holding the work down, as well as against the fence, as seen here with the MagSwitch version of a featherboard.

There is no reason why you can’t make your own pushsticks and featherboards – the important thing is to have them, and use them!!

So now we are moving onto stopping the work being thrown. Commonly called a kickback, the tools, such as a tablesaw, can propel your project towards you at speeds approaching 200km/hr. Believe me, they hurt when they hit! Never mind what you were working on is probably wrecked in the process.

There are all sorts of reasons why a kickback occurs, but it all boils down to one thing – instead of cutting, the tool somehow managed to get leverage on the workpiece. It could be that the kerf on the wood closed at the back because of forces inside the wood that were relieved during the cut, causing it to close on the blade, or you slightly skewed the piece so the back of the blade got a good purchase. It could be a misaligned fence, or (such as with a router) you fed the material in the wrong direction.

There are devices to try to prevent these occurring, such as splitters and riving knives, anti-kickback pawls, featherboards and board buddies (a kind of wheeled featherboard, where the wheels can only rotate in one direction)

I’m getting a bit of track here, so let me drag it all back to this:

To be safe during a cut, you want to keep yourself from being machined (to not split hairs here), nor do you want to be hit by self-made missiles.

By using guards, pushsticks and holddowns, combined with correct techniques, your chance of a mishap occurring is greatly reduced.

Safe woodworking.

A Quick Safety Tip

Imagine a barrier exists at least 6″ away from any spinning router bit, saw blade, or other cutting machine hellbent on getting you.

Can’t think of any better way to elaborate on that.  (Ok, I know I break this rule where it comes to scroll and bandsaws, but they are inherently a safer design.  However, they can and do still inflict significant injuries, and I certainly abide by this rule when my 1.3 TPI 3/4″ blade is running – scary bloody thing!)  (Well hopefully not literally obviously!)

I really wish I could afford a Saw Stop cabinet saw.  Even after years, they (tablesaws) still give me the willies (and that is probably a very good way to be, and even with a Saw Stop, I’d still feel and act the same, but at least there’s just that one extra thing acting as backstop if I EVER drop the ball).

Progress!

(Finally) was out at the shed a couple of days ago, getting some new footage for the next video, which I may even have finished by tomorrow (hopefully). It is a look at the raised panel router bit, and was my first chance to try out the new Incra Wonderfence that I have just fitted.

I don’t think that I can claim that there was any real difference (for this operation) between the old fence and the new, although I was able to fine-tune the outfeed fence very precisely, and it is that degree of control that you are really paying for with that fence system.

I always say that you can never really claim to own something until you have at least taken it apart and reassembled it, and ideally made some modifications, and even here I did a minor tweak of the fence. I was getting a tiny catch as the material was running onto the outfeed fence (despite being as inline as I could get it), so I have taken a bastard file and just put a slight radius on the leading edge of the outfeed fence. That helped dramatically, and solved one of my pet hates (and the very dangerous situation) of having your work get a hangup (ie getting stuck) partway through a cut.

When I have a little more time, I will make up some zero-clearance panels to use with the Wonderfence, and that will improve the situation even further.

Wood Dust and Respiratory Protection

When we are working in our workshops, we readily reach for eye and ear protection (well we certainly should be), and I think that I’m pretty good where it comes to being consistent in using these items of PPE (personal protection equipment).

Something that seems to get overlooked often is respiratory protection. Now I am sure that there are a lot of woodworkers who reach for the dust mask as readily as they do the rest of their PPE, but I know that I am a bit slack in that regard, and I’m sure that I am not the only one.

So I am going to try to do better. In part, my ambivalence towards dust masks is that the effect on the body is less easy to see than, say, the immediacy of a wood chip in the eye, or the ringing of the ears after using loud equipment. The bit of a cough, or poor night’s sleep just doesn’t carry the same weight to convince one to change bad habits – even though in the long run, it’s the lungs that will really make life hell if they’ve been abused.

The next couple of videos (which have been shot, but are still in the editing phase) are still the old me, bad habits and all. From then on, I’m going to make an effort to set a better example.

I’ve been doing a bit of research into it, and there are a number of solutions that are acceptable for the woodworking shed. The nuisance masks sold, often in packs of 5 for a couple of bucks are a complete waste of time. Sure, they cut some particulate out of the air, but they are not worth the paper they are made out of, when for just a few dollars more, you can get a properly graded dust mask.

There are (in Australia) 2 ratings for masks that are appropriate for woodworkers. P1 is usable in atmospheres where the particulate level is 4 times the recommended Occupational Exposure Level (OEL). P2 is usable in atmospheres where it is up to 10 times the recommended OEL. This is the level of mask I’ve decided to go with. Sometimes, it gets very dusty, and the cost difference between the two is negligible.

If you are working with finishes, you may also want to consider one that protects against gaseous contaminants.

Next, you need to choose what sort of mask you want – disposable or not, full face of partial. The cheapest are like a paper based mask, disposable, but don’t cope well for wearing over extended periods. They can be improved by getting one with an exhalation valve, which improves wearer comfort.

The next level is a more permanent mask – made of rubber, which then take disposable cartridges. These are definitely worth the money in the long term, and I used to use one for a long time (until one very hot summer when the rivers of perspiration filling the mask caused me to throw it away in disgust). Think I might get another one though – they are very good where it comes to respiratory protection.

The final level (well as far as woodworkers are concerned) is a full shield, such as the Triton Respirator

This provides a full range of protection.  A full face shield, quality ear protection (that can clip out when not needed) coupled with a hard hat.  The hard hat is not really necessary, but provides a good platform to attach all the components to.  For the respiratory protection, there is a shroud around the base of the helmet which restricts air access to the interior of the helmet, and an external air supply that causes a positive pressure inside the helmet.  This air passes through a prefilter which keeps the large bits of wood and dust out of the mechanics of the air pump, and then the standard air filters (typically P2 rating) to provide fully cleaned air to the helmet.

I have used the helmet a lot (to the point that I’ve worn out one of the shrouds, and two of the face shields – each is a consumable), but don’t enjoy wearing it where it is not necessary for the job.  It is a matter of the right tool for the job, and it is nice to have a range.  In the same way that a sledge hammer can be used for nails, and pins, it is better to have 3 different hammers, one for each type of job!

In Australia, all wood dust is considered carcinogenic, and the dust from manufactured board (such as MDF) is especially harmful. So hopefully this provides a bit of info that will help in making the right decision where it comes to respiratory protection, and I will be taking my own advice as well!

Timber Health Hazards

To quote the experts “In Australia all wood dust is now classified as carcinogenic (liable to cause cancer) This list has been compiled to give woodworkers a little bit of an insight into the potential health hazards posed by some of the timbers that are used.”

This site & list has been put together by U-Beaut Enterprises and is an excellent reference for (Australian) Woodworkers in particular.

While you are there, check out the range of finishing products and related accessories at http://www.ubeaut.com.au Have no doubt- you will hear more from me about their products (there is hardly a job I do that doesn’t include finishing with one of their superb range.) I believe their products are starting to be seen on shelves in the US, UK and Canada, and they are definitely worth seeking out.

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