|Mick B1||05/11/2019 14:15:46|
|1242 forum posts|
I've had one of my granddaughters making a pen body on my Warco when she was 7.
'Tain't the guard you have to worry about - it's their distraction of the thousand other incomprehensible (to them) things in yer workshop. You have to watch 'em like a hawk to see what they might pick up.
She made the pen fine, and without incident, but watching and teaching for an hour or two - whilst it was fun - was no trivial piece of work ...
|old mart||06/11/2019 21:08:55|
|797 forum posts|
I noticed that a good many people removed their chuck guard because it was badly designed, or just got in the way. Nobody seemed to think of designing and fitting an improved one.
This thread makes me think of parents taking their kids for a bike ride and dutifully fitting cycling helmets to their kids heads while going bareheaded themselves.
|Mick B1||06/11/2019 23:05:43|
|1242 forum posts|
I don't think that's gonna happen. Anything that works as a guard must also interfere with close examination of what's going on at the toolface. Anything transparent just gets crudded up in seconds, even when cutting dry.
|831 forum posts|
I've been using lathes on and off for over 50 years, but all the lathes I've used were old ones - my lathe at home is circa late 1960's early 1970's. No lathe I used ever had a chuck guard fitted, and I've lived happily without one, most of the time. The only time I would like one is when I'm using coolant, so save on the mess going all over the shed floor, but otherwise I've never felt I needed one. I never stand in way of the swarf coming off, never leave a chuck key in the chuck - my initial training left a huge impression on me - and don't use two chuck keys on 4 jaw chucks.
But I see new lathe increasingly have a guard fitted in front of the toolpost as well, and for the life of me cannot understand why. In my shed that would be the first thing to be binned, but there is only me in my shed.
My mill/drill had an interlocked guard fitted in front of the quill action bit. That got binned very quickly, it interfered too much with setting up processes. Too often guards fitted to machines prevents the operator from seeing exactly what is going on too. A temporary screen gets put in place to stop chips and coolant getting flung all over the shed, but is quickly able to be removed out the way when required.
The important thing about guards is that they should be designed with the operation and maintenance of the machine in mind, so that their interference with the discharge of both tasks are minimised. This should be borne in mind when guarding is designed, but is very often not, guarding usually seemingly being designed by someone sitting at a desk far away from the shop floor, who has never had to operate or maintain (or even seen?) the machine they are designing guarding for; if they had, that guarding would have surely been very quickly redesigned!
If a guard interferes with the natural operation of a machine by its operator, human nature being what it is, then ways will be quickly found to circumvent the guard - and from experience in production industry, that is a proven. Guarding design is not the walk in the park designers often seem to think it is. Anyone can slap a secure 'screen' around a machine or tool, but can you then operate it?
Remember also, whether in your own shed on your own or in the firms shop, an accident only ever happens due to there being an unsafe action taken or unsafe condition existing. It therefore the responsibility of all of us to ensure unsafe conditions do not occur, neither do we take unsafe actions, however we operate our machines or provide for our own safety.
Have a nice day!
|Mike Poole||07/11/2019 00:05:48|
2187 forum posts
Is a chuck guard a solution to a problem most people don’t have?
|Bob Brown 1||07/11/2019 00:07:18|
991 forum posts
When I purchased my Boxford AUD metric lathe (ex school) it came with interlocks on the chuck guard and gear cover so they both got removed as I like to apply a little oil to the gear train and the guard is just a pain.
|martin perman||07/11/2019 07:42:10|
1689 forum posts
Going slightly of track I've been using my local saw doctor a lot with them making me new blades for my powered saw, I aksed one day if they could show me their machines and was taken into the workshop where they had a mixture of old and new machines, one machine had a cover over it and I asked if it was still used and was told the the local health and safety office had insisted they fit guarding to it, the company said they couldnt because its design guarding would make it impossible to use so H & E banned them from using it. I think that we who have removed our guards have the same thoughts of the saw company, we use our machines knowing that we have to be careful and adjust our operations to cater for the lack of the guarding most of us use splash guarding which afford some safety but are easily removed to make setting easier. In industry I found that safety issues were addressed by putting physical blocks in the way as it was cheaper long term to do this than to train operators to properly use the machines, I say that knowing that mechanical blocks work and machine operators were cheap labour doing laborious repetative jobs.
|4858 forum posts|
No, they're a simple way keeping flying oil, coolant, swarf, and broken bits of metal out of eyes!
|284 forum posts|
Have not read all the replies to the OP, but enough to get a sense that there are 2 points of view.
My thought is that if it doesn't get in the way and does what it is intended i.e. stops you leaving the chuck key in, then why not leave it on? My Sieg C6 has one, and I'm glad it does. It doesn't stop lubricant or swarf flying about, it's not wide enough for that, just enough to cover the chuck body. It does make sure the chuck key is removed before I turn it on. It also makes a handy arm-rest when I need to use some emery cloth to polish something i've just turned. My Ideal lathe doesn't have one but I only run that at less than 500rpm and it is slow to speed up with slippage in the flat belt as the tension is applied so less potential damage if a chuck key is left in.
I have left a chuck key in the drill press chuck once. It has no guard. There is now a dent at face level on the side of a cabinet about 2m away, glad I wasn't standing in between them at the time.
|Robert Atkinson 2||08/11/2019 12:45:05|
406 forum posts
The problem is that you say you have taken that first "Unsafe action" - removing the guard- in your workshop. You also seem to be advocating removing guards to others.
Generally in industry it is insurance assessors that drive good behaviour regarding guards and the like. If they refuse cover you can't legally work (at least in the UK if you have employees or public access to your business) Note that even in the home workshop removing guards could have accident or life insurance implications if the worst happens and they find guards were removed. Not very likely but some insurance companies seem to be looking for any excuse to reduce a settlement or increase a premium.
|Robert Atkinson 2||08/11/2019 12:45:11|
406 forum posts
Edited By Robert Atkinson 2 on 08/11/2019 12:45:39
|Mick B1||08/11/2019 13:30:06|
|1242 forum posts|
Given that the presence of guards is often a lipservice provision by machine builders, and that we're supposed to be engineers capable of making up our own minds on a solution, I don't think any machine majoring primarily on its guards for USPs would likely make it into the bestsellers lists....
|old mart||08/11/2019 14:02:51|
|797 forum posts|
Dead right, Mick, machine builders have to supply their products with safety devices to satisfy the legislation, but there is nothing that says that the design has to be actually usable. Some of the worst designs are drilling machine chuck guards.
|Mick B1||08/11/2019 15:08:16|
|1242 forum posts|
Yes. Some seem to be intended to prevent anything cutting anything.
A cynic might say that the builders know full well that the first thing the buyer's gonna do is whip it off...
|not done it yet||08/11/2019 15:28:38|
|3576 forum posts|
... does what it is intended i.e. stops you leaving the chuck key in, then why not leave it on?
If that is all it is there for, it is no longer needed if all supplied chuck keys have springs on them, to prevent such scenarios. Guards are there to prevent operators getting entangled with moving parts. Further, can a key not be left in the chuck behind the guard (one of two used with a 4 jaw chuck). Probably most useful when turning between centres - but totally useless when using a face plate.
Leaning on a guard is not good practice if it is the flimsy plastic arrangement that one often encounters. Unfortunately the chuck guard does not generally help to prevent the operator getting tangled up with the workpiece. (who uses a lathe without something in the chuck?).
Making all lathes revolve one revolution very slowly, before speeding up would be a suitable substitute? Something that VFDs can be programmed to do for us. YIPPEE! a simple solution for many of us. Mine does this already, and it could be programmed for more than one ramp rate, if I so desired.
Put bluntly: Lathes simply cannot be made idiot-proof unless completely guarded from the operator - that means fully enclosed before starting the machine. Unfortunately, there are a lot of idiots out there - and lots of ‘no win - no fee‘ litigators awaiting easy pickings...
Edited By not done it yet on 08/11/2019 15:29:36
|4858 forum posts|
Note control panel, traffic lights, big red button and sliding door which must be closed before cutting starts...
Of course CNC machines like this are considerably more dangerous than a manual lathe. Automatic cutting and carousel tool changers, aerosol coolant sprays, multiple-spindles and several kilowatts to the motors. No-one wants to be inside one of these when it's running. These are what Health & Safety in the workplace are about and safe by design. Of my nearest engineering firm's thirty machines only two are manuals. Many good reasons for industry having a couple of basic machine tools handy, but they're increasingly less mainstream as the years roll by.
|831 forum posts|
Sorry Robert, but you are wrong in your criticism of me in both respects.
Regarding your "Unsafe Action", the guard was removed so that a potentially "Unsafe Condition" could be addressed. You seem not to have appreciated the significance of what was written in the whole paragraph. I said the guard interferred too much with the setting up process. This it did. If the job to be milled is not very well secured to the mill table then the likelihood exists that it can move when being machined. This could result at best with a damaged part and broken cutter; at worst the part could be flung off the table and cause the operator serious or possibley fatal injury. I like to try to avoid such situations arising so if the guard got in the way of me applying clamps etc and bolting it all down, being able to get the spanner on the nuts, then it is right in my mind to remove it. Better the job is securely fixed down. The last sentence in that paragraph said that I fitted a temporary - meaning not permanent thus removable - screen (guard) to stop swarf and coolant being flung out. I should have said that this is the length of the table giving a better length of protection; I could have also said that if it stops swarf and coolant being flung out it also stops me trying to put my hand in to the cutter area too, but I sort of assumed that folk reading that would figure that for themselves. So I removed a badly designed guard and replaced it with a better one, hardly an Unsafe Action.
No-where in my post did I advocate removing guards to others, so where you deduced that from is a mystery. Look, if someone wants to remove all the guards from their machine, or in reverse, totally enclose their machine with guards, then that is up to them. It is their machine, their shed, their responsibility; I would not presume to advocate any action to them, it's nothing to do with me, but having worked as a H&S advisor I would not advocate removing guards to others, unless, as in my case above, it is to be replaced with better guarding.
What I did try to do in my post was make the point that a) too often guarding fitted to machines is badly designed in that it prevents the operator in running the machine efficiently, or sometimes not at all as has been alluded to in other posts in this thread, or the maintainence engineer easily accessing the parts to be maintained, and b) guarding should be designed and fitted once the designer has seen for him or herself how the operator and engineer have to go about their respective tasks. A well guarded machine is usually a joy to operate in comparison to a badly guarded machine, and the bonus to the production manager is not only does he/she know it is a well guarded machine for their operators but production line efficiency usually rises as a result of it too.
Having been involved in the application of guarding to numerous machines, some built in a time before modern standards were required and thus were never designed to be guarded, I know only too well the issues involved. I also know, having seen first hand examples, the lengths some operators will go to circumvent badly designed guarding, human nature being what it is, leaving the machine in an Unsafe Condition.
|Robin Graham||12/11/2019 23:26:25|
|612 forum posts|
Thanks for further discussion - I'm still not convinced that leaving the key in the chuck is a hazard in my particular circumstances. By which I mean one man, one lathe and an established pattern of working. Obviously things are different in an environment where machines are shared.
I'm not going to the stake (or even A&E) in defence of that view though - I am retraining myself.
597 forum posts
See Martin Perman's post 3 posts above yours.
Sounds like you work for the council H&S. Or an insurance company....
597 forum posts
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