Dutton Kit Cars and their owners

I moved this off Paul's thread as well, it just seemed to be the polite thing to do...

The discussion regarding lighting may go on for a bit.

I've been using LED technology since the late 80's for various things. Special effect, model making, domestic lighting and of course car lights. I've experimented on three or four of my vehicles with varying degrees of success. LED's work best in an environment designed to suit them. Trying to fit a shallow angle led into something designed to accept a tungsten filament bulb is awkward.

CMV is all LED apart from thee headlight bulbs and the reversing lights. I've had about 8 different styles of indicator bulb trying to find one with an adequate light output. The ones I have fitted at the moment are the best I've had but they worked out at about £5 a pair compared to 80p for a tungsten one. 

I'd like to try and explain howto pick the right design of LED for the intended application and how each type differs.

Lets look at a normal light bulb  . These normally have a 'base' bayonet which fits into a socket. That socket doesn't need any light pumping into it as it it then wasted energy. So, the base is ideally a dark spot. Works with both types of bulb, tungsten and LED. The opposite end is 'normally' the bit that faces the outside world so chucking energy at it works for both bulb types - all good upto now?

Tungsten filaments work by passing electricity through a bit of wire and making it glow white hot, the hotter it gets the more intense the light. If this is trapped inside a glass case with an inert gas such as xenon it can get VERY hot and therefore will produce a good amount of light. As the glass case is transparent that light can escape in any direction which is why car light units have reflectors to spread the emitted light out and throw it in one direction. LED's however have a very narrow field of view. The 'filament' is actually two bare ends inside a tiny pocket of Gallium Arsenide... a pocket the size of a pinhead... when you look into an LED you can sometimes see one side is a cup shape and the other is a sparkplug shape electrode, the gas between the two electrodes reacts when charged to give off light, the chemical composition of the gas can be varied to produce different colour light. So when compared to a normal tungsten bulb the LED is way more efficient however due to the small size of the element the light output is smaller and concentrated into a beam by the small cup shaped reflector. The small cup shaped reflector also means the 98% of the light is thrown in one direction in a narrow beam. 

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Talking of LED lighting, this is the bridge from Cornwall, with its new lighting.

I don't really like LED indicators and I definitely don't like DRL's. If there was one thing I won't miss about the EU it would be DRL's. On the other hand I like my LED spot lights in the house and they look good on the Tamar bridge in that picture. So I wonder whether I'd like other people having LED headlights.

DRL's ? world seems to be full of TLA's these days :(

DRL = Daytime Running Lights

TLA = Three Letter Acronym

ETLA = Extended Three Letter Acronym (i.e. a 4 letter one)

In my business we love TLA's but on one of my projects I decided that we'd go one better and everything had ETLA's.


never have understood the need for DRL's in the UK. There's no road traffic requirement for them and there's never been an EU directive. Only Sweden has them as mandatory. And yes our corp. is very TLA and Buzz work heavy :/

Interesting, a legislative requirement for them to be fitted but no road traffic requirement for their use. RTA still only requires headlights or parking lights or no lights at all.

I don't think that there has been any research done to show that LED DRLs actually reduce accidents. The Swedes introduced them but they were incandescent lights, which were more like sidelights. It might make some sense in the northern reaches of Europe but they a pointless in southern Europe. The eco-friendly insistence that they use LEDs changes the effect on people and rather than noticing the presence of a car we see a fascinating point of light (or points of light) and it does not trigger the same flight response - we just stare at them as the car runs us down.

Similarly I find that I don't notice LED indicators as well as I notice incandescent bulbs. The LEDs are completely off, then completely on etc but I don't see it the same as the pulsating light of a 'real' indicator.

my car has all the lights as LED's.......the headlight bulbs might be halogen bulbs......or LED's not decided yet, depends how good the LED's are.

with you on the DRL's though......

Went over that the other day on the train
First time to Devon /cornwall,well impressed will definitely be visiting again

bought one of these . straps around your head. great for dark spots, when working on car.  £2.50 :-)

lol cheers you sweet talking bas8ard 


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