Model Boat Mayhem
Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: colin-stevens on September 12, 2008, 09:58:46 pm
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any one got any ideas on how i can get/adapt lights to work underwater?
got some 5v bright white LEDs from Maplins. thinking of clumping them together in groups of 3 or 4. thing is they are clear, all round. this means it is "wasting" light where i dont want it, round the sides, but more importantly, out the back. plan on having a few of these units. maybe mount them in a tube, but cant find a descent reflector, or lens. taken a long boring wander round town centre trying to find something, no inpiration there.
so, any sugestions
Ta
colin
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Hi Colin
Have you tried fixing the LEDs in the tube firmly, pointing them downwards and placing some silver paper (fag packet stuff) behind the cluster, so as not to touch the contact wires. This should reflect all available light back down the tube, which could also be coated with said paper.
Of course, you could always use Fibre Optic strands (like I do). One bulb sending it's light to a hundred tubes. O0 I pick em up cheap in the pound store type places at Christmas time.
Hope this helps
ken
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coming from the south, we dont have pound shops. not posh enough. shame, lots of goodies to be had. in fact i'm sure thats where i coulld get miniture torches or something.
just mounted 3 LEDs in a row in a strip of plastic, get an encouraging amount of light beam. so, using baking foil, make a bit of a reflector and dont worry about a lens. see what occurs.
keep the inspiration coming.
colin
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A lot of white LED's on the market have a 25 Degree forward viewing angle - with very little light emission from the sides of the LED.
Not sure what size yours are? An extract from the Maplin spec for the 3mm Nichia white LED:
Order Code N30AT: High Power White
Nichia description: NSPW300BS
Viewing angle: 25°
We use loads of these in our working lights, sometimes the restricted viewing angle is too narrow for some of our applications.
Regards, malc
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The LEDs will focus the light forwards although a little radiate from the sides and back. Could you paint the body of the LED to mask the light leakage or mount it in a holder?
Neil
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Have you thought about adapting one of these little beasts? They are very bright and focussed; come in different sizes and voltages, and I bet you could use the LED and lens part without having to fit the battery tube immediately behind it i.e. use a remote battery pack.
http://www.maplin.co.uk/Search.aspx?menuno=13050
FLJ
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Colin , i think kenny may have the best idea using fiber optics ,if your not in a rush just wait another 3 months and there will be loads of fiber optic xmas trees in the shops and skips for you to salvage .
Or you could go along with your idea of grouping them together inside a piece of tube and then sealing them in with either black silicone or resin with black paint mixed in ,do your wiring first and you have a waterproof housing O0 .
just an idea.
daz
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i use white LED's on my research sub, mounted into a plastic tube, this tube is sprayed with a chrome effect spray available from the car shops
the chrome spray takes a while to dry but if you have prepared it well you get a good smooth and fairly reflective finish, - yes its not mirror like but it is very reflective, i then seal the power feeds to the rear of the leds with clear cast ( paperweight style) clear resin, leaves me with waterproof light pods that work very very well !
i ran at the hertford clubs night sail some years ago, pitch black rural location and then just beams of light in the murky depths...awesome fun !
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Most white LED's I have encountered use 3-3.5 volts forward voltage, why are yours 5 volts?
The lens of the LED should ensure virtually no light is emitted around the sides and certainly not the back, as someone mentioned most LED's have a fairly narrow beam. Exceptions are versions like Osrams Golden Dragon series, which have built in reflectors and beam angles of 120 degrees or so.
Andy
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Sorry Andy ,but must have got the wrong led's mine leak light out the back ;D
(http://i168.photobucket.com/albums/u176/darran77/dutch%20river/P1000403.jpg)
daz
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Hi colin, iwas looking at Fibre Optic strands from http://www.component-shop.co.uk
sorry dont know how much if u e-mail them, thay will help
Andy
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Sorry Andy ,but must have got the wrong led's mine leak light out the back ;D
(http://i168.photobucket.com/albums/u176/darran77/dutch%20river/P1000403.jpg)
daz
The light output from the back is tiny compared to what is put out from the front, whcih is evident from your photo.
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Hi
Could you blob (technical term) some black silicone on the back to shut off the leakage of light?
R,
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Hi
Could you blob (technical term) some black silicone on the back to shut off the leakage of light?
R,
Yes. For underwater use, it helps if the blob extends over the bare metal of the component legs and soldered join on to the wire insulation. Depending on the size, it could be enclosed within a plastic drinking straw to give a workmanlike appearance. Just leave the business end poking out.
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There are also underwater lights for aquarium use available , some run off of DC battery sources.
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This ismlate in the day but (and I may have missed some of the posts) ( too tired to read OR cant) but what are the under water light for? sorry a blonde moment and yes I is one {-) aoh boy do I have fun O0
R,
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On the Maritimo's and other sports cruisers they are purely "w**k" factor, I shouldn't say it because installing them pays my bills ;).
They do look cool though.
Photos from an early morning start to a fishing trip on a boat I installed electronics onto.
2 Cat C12's 715Hp for catengineman on a 40 footer.
Regards
Nick
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any one got any ideas on how i can get/adapt lights to work underwater?
got some 5v bright white LEDs from Maplins. thinking of clumping them together in groups of 3 or 4. thing is they are clear, all round. this means it is "wasting" light where i dont want it, round the sides, but more importantly, out the back. plan on having a few of these units. maybe mount them in a tube, but cant find a descent reflector, or lens. taken a long boring wander round town centre trying to find something, no inpiration there.
so, any sugestions
Ta
colin
http://www.modelboatmayhem.co.uk/forum/index.php?topic=13114.0
Could this help?
If so, then proves Martin does' have his uses! :D
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Looking at the site again, I think you will need to build a rather big boat for these lights!
Sorry if no good. :embarrassed:
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I used 4, 10 mm high intensity blue leds, it gives a similar effect to the full sized boat in my previous post, just drill a 10 mm hole in the hull, use some epoxy and push it through from the inside. the flange on the led with epoxy gives a watertight seal. I havent bothered blocking the light from the sides as its minimal, the shape of the led acts like a lens focusing the beam.
Nick
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Perhaps a reflector replacment for one of those mini maglites?
http://www.action-lights.com/flashlights/maglite/replacement-parts/108-038-reflector.asp?bhcp=1
I cast my own housings around LED, and paint the sides white or silver before blacking them out.
No reason they wouldn't work under water..
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Hey Umi_Ryuzuki, those lights of yours look really neat. You should sell those on E-Bay or something. :-))