Model Boat Mayhem

Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: riggers24 on September 09, 2006, 02:39:24 pm

Title: Grain of wheat bulbs
Post by: riggers24 on September 09, 2006, 02:39:24 pm
Can anyone tell me where I can get 6v gow bulbs from. I can't remember where I got the last ones from.

Marc
Title: Re: Grain of wheat bulbs
Post by: cbr900 on September 09, 2006, 02:40:14 pm
EBAY there are heaps of them on there..

Roy
Title: Re: Grain of wheat bulbs
Post by: riggers24 on September 09, 2006, 05:02:56 pm
not at the minute can only see 12v listed
Title: Re: Grain of wheat bulbs
Post by: Colin Bishop on September 09, 2006, 05:28:08 pm
Squires do 12v, 6v and 3v GoW bulbs  in red, green, amber and blue. 40p each or £1.75 for 5. Also do clear ones in same voltages a bit cheaper. They do grain of Rice bulbs too but only 12v.
Title: Re: Grain of wheat bulbs
Post by: Mankster on September 09, 2006, 06:03:20 pm
Also from here http://www.huntersystems.co.uk/acatalog/Lighting.html
Title: Re: Grain of wheat bulbs
Post by: HS93 (RIP) on September 09, 2006, 06:08:11 pm
I sometimes use 12 v bulbs on 6v it can look better,  and lasts so much longer ,really handy for hard to get to places where changing can be a problem. try a few in the dark they give a better scale effect. Peter
Title: Re: Grain of wheat bulbs
Post by: Colin Bishop on September 09, 2006, 06:16:59 pm
Quote
I sometimes use 12 v bulbs on 6v it can look better,  and lasts so much longer ,really handy for hard to get to places where changing can be a problem. try a few in the dark they give a better scale effect. Peter

I would endorse that, I usually do the same, especially with navigation lights. If you look at full size ships at night the nav lights actually look quite dim, particularly the port and starboard ones.
Title: Re: Grain of wheat bulbs supply
Post by: BarryM on September 11, 2006, 08:28:26 pm
www.proopsbrothers.com do GOW in 12 or 6v.  Full size practice is to use 40W multi-filament bulbs in navigation lights. Thus they are hardly in the searchlight category.
Title: Re: Grain of wheat bulbs
Post by: cbr900 on September 12, 2006, 05:47:35 am
Why do they have so dull I would have thought the brighter the better, more visible..


Roy
Title: Re: Grain of wheat bulbs
Post by: BarryM on September 12, 2006, 08:28:05 am
Roy,

Under normal visibility, 40W can be seen for a long way at sea and does not affect the night vision of bridge watchkeepers.  As the reason for navlights is to enable a watchkeeper to determine the course, activity and  size of another vessel (and thus the threat it poses to safety), there is no point in fitting lights so bright that they can be seen almost over the horizon. At that distance the vessel is no threat to anyone.

By the way, have you ever checked the wattage of a lighthouse bulb? - I think you will find that they are little different in power to navlight bulbs. It's all down to the lens system.

Cheers

BarryM
Title: Re: Grain of wheat bulbs
Post by: cbr900 on September 12, 2006, 03:19:43 pm
I have made mine quite bright as I like to be able to see them when turned on in daylight, I can understand what you have pointed out, but I very rarely sale of a night, so I fitted 18,000 candlepower leds in all lights and they can readily be seen in daylight, but that is personal choice..Thank you for the reason for the full sized versions...


Roy
Title: Re: Grain of wheat bulbs
Post by: Voyager on September 12, 2006, 07:25:39 pm
Does using 12v bulbs under 6v power effect the life span of the bulb, does it increase or decrease?


Voyager.
Title: Re: Grain of wheat bulbs
Post by: BarryM on September 12, 2006, 08:33:33 pm
Voyager,

Should increase life - less thermal stress on filament. Whether or not the light output is acceptable though......

BarryM
Title: Re: Grain of wheat bulbs
Post by: DavieTait on September 12, 2006, 09:23:46 pm
We used to use normal 60w 240V bulbs in our port & starboard navigation lights , with 100W 240V in the mast lights ( especially the all round white ). This is standard practice in the fishing industry as a 40w bulb can be seen 12miles away but due to the mast head all round white being 20ft higher up it needs to be brighter as it can be seen up to 24miles on a good night. The wheelhouse interior lights are not allowed to be more than 40w ( in fact its normal to not use the interior light at sea but use very small 12w map reader lamps next to the chart table or pc keyboard ). I have seen red lamps in a fishing boat wheelhouse for the same reason's as the RN use them at night , the red light means your eyes adjust to the darkness in seconds instead of 2 minutes or so.

For scale i'd use the 12w GoW bulbs but run them on 6v which will looks far more realistic and will allow them to last at least twice as long.

Davie
Title: Re: Grain of wheat bulbs
Post by: Halley on September 13, 2006, 07:47:04 am


Davie

Your feedback provides the sort of information that landlubber modellers would otherwise have no access to.  It is invaluable.  Many thanks.

As far as models are concerned, the guys that build and sail them want to see lights working, and scaling the light output from model fittings necessarily reduces the impact that the lights make?

My feeling is that all but the scale purists will want to see navigation lights that are somewhat brighter than would otherwise be the case? (visions of old farts staggering around in the dark and falling into ponds everywhere)?

Personally, I've always been reluctant to use grain of wheat and grain of rice bulbs even at reduced voltages because they are filament lamps and often fail unexpectedly.  The wiring 'tails' on these lamps do not aid easy replacement when routed down the inside of a mast, or through superstructure either.  My own choice is for LED's, selected to have the widest viewing angle possible and with a larger value resistor than specified fitted to dim them acceptably.  The benefit is that with a minimum 100K hour working life, they're going to outshine most modellers!


Title: Re: Grain of wheat bulbs
Post by: Subculture on September 20, 2006, 03:54:12 pm
I only use LED's. Less fussy about voltage range(providing you know how to wire them up correctly and use a voltage regulator) and last forever in a model application.

Cheap too.

Andy