machine lighting

I just replaced the bulbs in the living room wall lights with led ones. I bought a load of gas works style fluorescents that looked ok in them - short spiral ones. Most have gone so I thought I would try led especially when I found B22 fittings are available and later in G45 as well. These are nice and compact. The light is less harsh than the spirals. I only fitted those because I was fed up with bulbs blowing where ever I bought them from. Out of curiosity I looked at the light out of the led lights with a spectroscope. No spikes, unlike the spirals. Must admit that surprised me and I suspect it's down to the white envelope that forms the bulb shape and contains the leds. At 4.5w they are supposed to be equal to 45w tungsten. I'd say a bit more as the light is a little more directional in a g45 shape.

John

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I've seen a few people using these LED strips for lighting machine tools. They are low voltage, waterproof and self-adhesive, can be daisy-chained (using a variety of X and T pieces etc) and are available with remote control and dimming function. And available in a variety of colours including warm(?) white.

The problem I found with the popular single LED "Jansjo" spotlight from Ikea (not the one John talks about), is the point source nature of the light. It casts sharp, contrasting shadows, so although you may have a fair bit of light on the target, everything else is in relative shadow - unless of course you have good backlighting too, which suggests a better solution.

My preferred solution now is to have several panel or strip lights on the ceiling so that there is good, diffuse lighting throughout. When I am finally released from this armchair workshop into a real one again, I will be fitting some of those 36W LED luminaire units from Screwfix or Toolstation. Good news is that we finally move into a new to us house tomorrow.

Haha, 3.5 diopters. I wish. I can do better than that by a factor of 2. I should get some form of disability allowance but it means that I can focus on small objects about 2-3" from my eyes by removing my glasses, a sort of macro vision. Pity I am completely lacking the talent to be a watchmaker.

Merry

Edited By Muzzer on 14/02/2016 11:40:55

Those luminaire units linked to by Muzzer look interesting but why the huge disparity in price for what looks to be the same thing? I'm getting tired of changing out 58 W fluorescents in my workshop. Lucky to get 5 years out of a tube, estimated 3,000 to 4,000 hours life so those luminaries may work out cheaper in the long run.

Screwfix apparently don't have the best reputation for LED lights, some of their ranges have apparently been short in life and low on performance.

Warm white isn't best for worship use tho'. The colder lights may be harsh but seem much better for seeing details. For the lathe I have an old style build on articulated arm light and a LED strip style unit, Lidl special about 4 years back, 2 ft 6 or so above and a foot behind centre line to give general local light to supplement the shop lights.

Clive.

> Warm white isn't best for worship use tho'.

I thought altar candles counted as warm white

Neil

Out of interest I discussed lighting with a swedish lighting engineer who happened to be around when the topic cropped up. Seems that only warm white led lighting is available there. I wonder why, no point in repeating myself. That's what IKEA sell too. I reckon that they are a touch cooler than the usual tungsten lights. Most fluorescent tubes are warm white too. I've fitted some that should be suitable for colour work according to some standards but I'm not sure I like them so I guess the tubes I bought will last for a very long time. Mind you they should stop me from suffering from SAD. Not that I ever have.

The led lights I linked to use 15 or so led chips over an area so none of the point source problems.

John

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The person that started Screwfix up sold it to the B&Q stable. He kept prices down by being careful about what he stocked. After he sold it he started up ToolStation. Same basic idea. Looks like the Wicks stable has bought that now.

I had heard from a friend who it seems has talked to him that he is going start up another.

John

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Toolstation is in Wicks round here. Not sure how normal that is. Since I selected the local store it shows me how many of the items I look at are in stock in that store. They seem to be working on the basis of keeping a few of everything were as the local Screwfix has lots of people in it and is pretty big which must up the costs.

I generally buy power tools via brand name now and use mail order. I did buy some B&Q power pro stuff but that doesn't seem to be an option any more. It was fairly decent stuff hence giving trade users a more restricted guarantee.

John

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Edited By Ajohnw on 14/02/2016 20:05:25

I've used several of the IKEA angle-poise type lights in my workshop in the past, works a treat.

I've just bought one of the freestanding bendy led lights, planning to add a bracket instead of the freestanding heavy base.

Should be just right for the mini lathe!

David J

I'm using a lot of GU-10 light fittings with 4W to 6W "Daylight White" LED spotlight bulbs and find the colour temperature is excellent for fine work, by using several lights in different positions to illuminate a workspace it's possible to eliminate problems with the shadows of hands, tools or work on the workspace,

- Nick

The white envelope couldn't of itself add any extra spectral lines. LEDs normally emit quite a tightly defined spectrum. I believe that some "white" ones use 3 separate LED types to appear white through mixing appropriate primary colours, but other white types actually emit ultraviolet and use fluorescent-type phosphors to convert to white.

I've seen on here a reference to strobe effect on machine lighting and a lathe could appear to be stationary when its actually running ? Well , on Sunday i bought some clear LED bulbs ,with fake filaments in screwfix ,for the living room .....and when the dog wags his tail , it looks like he has a dozen tails !!!!   Hertz  indoors noticed it first...

Edited By Hacksaw on 21/12/2016 15:17:00

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I like that

It's quite likely that many LEDs will flicker. The exception would be those that are powered by a DC supply rather like a laptop PSU. Many of the standalone drivers are "constant current" devices that use PWM to regulate the current. Most external car lights (including some headlights) are LED and you get a fairly obvious strobing effect from them.

Mains bulbs don't have the space or the need to accommodate the components required to provide a flicker-free output. I noticed that the trendy "LED filament" bulbs are little more than a series capacitor (to limit current) and a bridge rectifier. They will certainly flicker at 100Hz.

If you do the sums, you will find that a capacitor that will store enough energy at around the typical bulb voltage will end up about the same size as the bulb itself - and cost more. The PSUs mentioned in the first paragraph store their energy at ~340Vdc and the required cap size is significantly smaller.

I'm not convinced there is any significant risk unless you are stone deaf, mind.

Murray

The halogen lamp on my VMC is absolutely fine in spite of the light being quite yellow. The cool white LED lamp I bought for my Lathe however is pants. I won't be buying any more LED lighting until the light quality improves.

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Do yourself a favour, Vic ... try some 'Warm White' LEDs before giving-up on them.

The CRI [colour rendering index] is typically much better.

MichaelG.

I've been testing LED lighting since they first popped up as replacements for conventional mains bulbs.

Cool White tends toward the blue end of the spectrum and is rubbish for detail vision.

Warm White is better than Cool White but tends to the orange/red end of the spectrum and still isn't brilliant (no pun intended) for fine detail vision.

For a reason I cannot fathom what no shops tend to stock are "Daylight White, which are a well balanced bright white light very well suited to fine detail vision,

- Nick

Anyone got a guitar handy ?

I was just being Jimi Hendrix at Monterey , playing Like a Rolling Stone....when.

Check out the open A string struck under LED filament 240v lighting !!!

Hertz (i guess )is a similar frequency.... I thought my eyes had gone wonky for a minute!