Risk Assessment

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Clive India on 09/08/2016 13:08:10:

Nice one Michael!
I look forward to seeing the risk assessment for the lamp in your workshop.

.

Clive,

Using the distinction that I suggested above … Whilst you will never see a ,'Risk Assessment' for my lamp usage, I can assure you that there has been plenty of 'risk assessment'. The result being that I only ever use low voltage lighting on machinery. Any mains voltage is kept at the distal end of the wiring, away from flying swarf and coolant.

This is hardly a difficult or novel, decision; it simply reflects good industrial practice.

Several times on this forum I have warned against the use of GU10 LED lamps as machine lighting, and I rejected the 'magnetic sewing machine lamp for the same reason.

There … That wasn't too difficult, was it ?

MichaelG.

[Ed DuffnerParticipant @edduffner79357]

Talking of no-win/no-fee ads. That guy who is supposedly a tradesman (probably an actor) that falls off a ladder and won a case aginst his employer for "giving him the wrong ladder" is a bit far fetched IMHO. If he's a qualified and experienced tradesman he should know what access equipment he needs to carry out a particular task and if using a ladder to know if it needs to be footed or tied off etc.

Whilst at HP I developed a pain in my right wrist because I used the mouse quite a lot for doing application support and tended to place a lot of my upper body weight on that wrist (no idea why). I asked if I could have one of those gel wrist rests. What I got was a visit from an EHS rep who sat and watched how I worked for about 30 seconds, then decided I needed a chair to the cost of about £400. I got the chair and continued to get pain in my wrist. I was later told by a colleague there was a gel wrist rest in the stationary cupboard. I grabbed it and after using for a few weeks the pain started to go. The chair was so arched in its design it started to give me back pain so I stopped using it.

Ed.

[AjohnwParticipant @ajohnw51620]

Posted by Michael Gilligan on 09/08/2016 15:47:15:

Posted by Clive India on 09/08/2016 13:08:10:

Nice one Michael!
I look forward to seeing the risk assessment for the lamp in your workshop.

.

Clive,

Using the distinction that I suggested above … Whilst you will never see a ,'Risk Assessment' for my lamp usage, I can assure you that there has been plenty of 'risk assessment'. The result being that I only ever use low voltage lighting on machinery. Any mains voltage is kept at the distal end of the wiring, away from flying swarf and coolant.

This is hardly a difficult or novel, decision; it simply reflects good industrial practice.

Several times on this forum I have warned against the use of GU10 LED lamps as machine lighting, and I rejected the 'magnetic sewing machine lamp for the same reason.

There … That wasn't too difficult, was it ?

MichaelG.

I use a mains led light as a machine light. It's well above the machine. Throws out far more light and needn't be close to the work area on the lathe. The mains lead runs next to the mains feed to the miller. That along with the power to the inverter will get put in plastic trunking when I re-site it from it's current position.

The same light would be ok for the miller as well but to get shadow free I would need 2. That may get fixed with low voltage lighting. I have a couple of the flexy stemmed LED ones Ikea do and may modify them to mount directly on the head but I have noticed that certain fishing headlamps give out far more light than these seem to do. It should be pretty easy to rig up a power supply for them rather than run them on batteries

The lamp for the lathe is from Ikea, used with the clamp. The pool of light is big enough to avoid having to move it around.

**LINK**

John

–

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Ajohnw on 09/08/2016 18:00:23:

I use a mains led light as a machine light. It's well above the machine. Throws out far more light and needn't be close to the work area on the lathe.

.

The risk is the same … We have simply chosen different mitigations.

… Absolutely nothing wrong with that.

[and only the worst of pedants would question your definition of a 'machine light' ]

MichaelG.

[Mark CParticipant @markc]

Many (especially cheap) mains led bulbs are 50 Hz strobe lights…..

Mark

[AjohnwParticipant @ajohnw51620]

Posted by Mark C on 09/08/2016 22:45:50:

Many (especially cheap) mains led bulbs are 50 Hz strobe lights…..

Mark

MIchael G may have taken photo's through a microscope using a certain type of camera. If he had he would know that all light's intensity varies at 50Hz if it's mains driven. They don't if driven with DC. LED lighting generally used switch mode drive anyway.

Fluorescent lights have more of a strobe effect but having tried to get a Chipmaster chuck to look stationary at 3000 rpm many times and never succeeding it doesn't bother me at all anyway.

John

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[brickyParticipant @bricky]

On a lighter note[no pun intended] whilst working at a college I was at the top of a ladder and my mate was holding it .this was on a stairwell landing.The safety officer on her way down the stairs said to my mate "where's your hat,get one"Off he goes and on her return she blew her top as he was wearing a chefs hat,this she reported to the management.Nothing was said.On his retirement from the college he was presented with a chefs hat,proving there is some humour in H&S.I go to his funeral on Friday and will always remember him and his pranks.

Frank

[Martin KyteParticipant @martinkyte99762]

"Many (especially cheap) mains led bulbs are 50 Hz strobe lights…..

Mark"

Shouldn't that be 100Hz?

Martin

[Mark CParticipant @markc]

Martin, it depends how cheap they are!

Mark

[Martin KyteParticipant @martinkyte99762]

2 current 'humps' per 20mS is 100 Hz

[AjohnwParticipant @ajohnw51620]

Posted by Martin Kyte on 10/08/2016 10:46:45:

2 current 'humps' per 20mS is 100 Hz

I was expecting some one to say that they can see the flicker.

Truth is they are likely to be switch mode driven in some fashion at a much higher frequency and there probably is some variation in light output at a 100hz. So what ?

John

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[Michael GilliganParticipant @michaelgilligan61133]

Posted by Martin Kyte on 10/08/2016 10:46:45:

2 current 'humps' per 20mS is 100 Hz

.

Martin,

I think Mark's point was that the cheapest of the cheap may only use half-wave rectification.

MichaelG.

[Mark CParticipant @markc]

Yes Michael, I have some that simply have a single led chip running from a resistor – the resistor tends to burn out which is how I know what was in them.

You might cram a switch mode psu in a gu10 sized bulb but I have my doubts you can get one into a g9 format, open to being shown one and proven wrong mind.

Mark

[Martin KyteParticipant @martinkyte99762]

OK so I was being a little tongue in cheek.

Seriously though:-

All my designs for led drivers operate at 600kHz plus for the current regulator switching frequency and I generally pulse width modulate at between 1 and 2kHz for dimming. This is at least an order of magnitude faster than biological processes so the cells don't respond to the flashes.

On a slightly different line I don't see why fibre-optics should not be used to effect for a milling light. I have used them for getting photons onto fly brains with the light sources (LEDs) remote from the cells to eliminate heating effects. In that particular instance we needed about 10mW/square mm which is a lot brighter than you want to stare at in order to oxidize stain in fly brains for neural imaging.

regards Martin

[SillyOldDufferModerator @sillyoldduffer]

Posted by Martin Kyte on 10/08/2016 12:10:03:

OK so I was being a little tongue in cheek.

…

I have used them for getting photons onto fly brains …

regards Martin

I suppose that involves using a fly-cutter?

Joking apart that's really interesting. What sort of microscope and stain is used?

Ta,

Dave

[Martin KyteParticipant @martinkyte99762]

I think that was done on one of the confocals using florescence although I could be wrong. I didn't get involved in the imaging side on that occasion. Regarding Fly-cutters they do have to dissect the brains out of the fly. We are talking Drosophila Melanogastor (Fruit flies) rather than great big Bluebottles.

Martin

[Neil WyattModerator @neilwyatt]

Posted by Ed Duffner on 09/08/2016 15:54:20:

Talking of no-win/no-fee ads. That guy who is supposedly a tradesman (probably an actor) that falls off a ladder and won a case aginst his employer for "giving him the wrong ladder" is a bit far fetched IMHO. If he's a qualified and experienced tradesman he should know what access equipment he needs to carry out a particular task and if using a ladder to know if it needs to be footed or tied off etc.

Whilst at HP I developed a pain in my right wrist because I used the mouse quite a lot for doing application support and tended to place a lot of my upper body weight on that wrist (no idea why). I asked if I could have one of those gel wrist rests. What I got was a visit from an EHS rep who sat and watched how I worked for about 30 seconds, then decided I needed a chair to the cost of about £400. I got the chair and continued to get pain in my wrist. I was later told by a colleague there was a gel wrist rest in the stationary cupboard. I grabbed it and after using for a few weeks the pain started to go. The chair was so arched in its design it started to give me back pain so I stopped using it.

Ed.

My wife bought me a gel wrest and it cured RSI problems that had my arm feeling like it was freezing.

That said I spend too much time sitting down at home these days, but after getting back ache I invested in a cheap 8 hour design and it's much better*.

Neil

*When I was a 'boss' I got rid of my leather covered executive chair and used an ordinary typists chair. We bought one staff member one of those strange kneeler on wheels things. It was very odd to use and I worried about putting my knees out getting off it!

[Neil WyattModerator @neilwyatt]

Posted by Martin Kyte on 10/08/2016 12:10:03:-

All my designs for led drivers operate at 600kHz plus for the current regulator switching frequency and I generally pulse width modulate at between 1 and 2kHz for dimming. This is at least an order of magnitude faster than biological processes so the cells don't respond to the flashes.

Roll your eyes when looking a many LED type lamps and you will see after images that show many are driven at much lower frequencies from car sidelights to traffic lights.

Neil

[MWParticipant @mw27036]

Posted by Martin Kyte on 10/08/2016 12:33:29:

I think that was done on one of the confocals using florescence although I could be wrong. I didn't get involved in the imaging side on that occasion. Regarding Fly-cutters they do have to dissect the brains out of the fly. We are talking Drosophila Melanogastor (Fruit flies) rather than great big Bluebottles.

Martin

So..frankenstein getting up to much these days?

Michael W

[SillyOldDufferModerator @sillyoldduffer]

Posted by Martin Kyte on 10/08/2016 12:33:29:

I think that was done on one of the confocals using florescence although I could be wrong. I didn't get involved in the imaging side on that occasion. Regarding Fly-cutters they do have to dissect the brains out of the fly. We are talking Drosophila Melanogastor (Fruit flies) rather than great big Bluebottles.

Martin

Thanks Martin, good stuff. Drosophila brings back some memories that I'd completely forgotten. It's 1970 and there are no flies on me, ho ho.

There was a "types of microscope" question on "Only Connect" in the week that I completely failed to get. As I had to look up confocal too I'm obviously horribly out of date.

Regards,

Dave

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Martin Kyte on 10/08/2016 12:10:03:

On a slightly different line I don't see why fibre-optics should not be used to effect for a milling light.

.

Perfectly fine, provided you can pick-up a suitably sized bundle [or ringlight] at an affordable price.

Retail prices for Schott items are eye-watering for the hobbyist. **LINK**

http://www.astroshop.eu/microscopy/microscopy-accessories/lighting/23_60_40/m,Schott/a,Mikroskope.Allgemein.Serie=KL-1500-1600-2500

MichaelG.

[AjohnwParticipant @ajohnw51620]

The microscope type fibre optic lighting can be picked up more cheaply 2nd hand. I sold one where the fibre optic cable split into 2 which might be a better option than a ring light for general use in other areas.

There are also some pure ring of LED's ring lights about. I tried one for macro photography – hopeless compared with flash.

I've been wondering about certain LED lamps that are usually attached to bikes, even motor bikes but a lot of them have plain glass at the front. I know from my headlamp and a couple of Ikea lights that they need an odd shaped lens on the front for an even beam. A couple of the heads on the Janjo range could be positioned pretty close to a milling cutter if needed. They are all on flexi-stems. As the distances could be fairly short it would make up for the light output levels. Not so good on a lathe as more distance is a good idea.

John

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[Alan VosParticipant @alanvos39612]

Posted by martin perman on 08/08/2016 20:45:54:

the site rules insist you have to wear gloves, have you ever tried to wire up a control panel with gloves on its very difficult to bloody impossible

I am not an electrician myself, but I do visit building sites, where I wear the company standard PPE, which is for electricians. We all have gloves with open ended thumb and forefinger, specifically to address that problem. The sites I visit are all major office developments, with large safety budgets and many safety elves. So it can be done. Sorry, I don't know the exact rules by which this is allowed. So can't say if there is some key difference in situation which would not allow the same.

[martin perman 1Participant @martinperman1]

Posted by Alan Vos on 10/08/2016 19:07:45:

Posted by martin perman on 08/08/2016 20:45:54:

the site rules insist you have to wear gloves, have you ever tried to wire up a control panel with gloves on its very difficult to bloody impossible

I am not an electrician myself, but I do visit building sites, where I wear the company standard PPE, which is for electricians. We all have gloves with open ended thumb and forefinger, specifically to address that problem. The sites I visit are all major office developments, with large safety budgets and many safety elves. So it can be done. Sorry, I don't know the exact rules by which this is allowed. So can't say if there is some key difference in situation which would not allow the same.

If it were that simple, the arguement is the gloves are to protect the hands and cutting the fingers off is loosing the protection, we work in Hospitals, research facilities and universities which I assume is the same as offices etc, the only difference I can see is wiring buildings have larger wires where I work with considerably smaller wiring and with gloves on you loose the feeling of the wires.

Martin P

[Nick_GParticipant @nick_g]

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