Joined: Aug 2017 Posts: 120 Threads: 6
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Location: Suffolk
Try JB Vintage Spares. Is that your bulb first on this page?
http://www.jbvintagespares.co.uk/shop/45...ight-bulbs
Suffolk, UK
1925 Chummy
1934 Box
Joined: Aug 2017 Posts: 178 Threads: 1
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30watt x 2 is to high a current rating for an Austin dyamo to keep up with,this is 10 amps for the head lamps plus tail lamps then the current drawn by the coil. A much better solution would be to use L E Ds, a much better light output. Hope this helps.
Joined: Aug 2017 Posts: 481 Threads: 14
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Location: Dunchurch, Warwickshire
Please note that the dynamo does NOT have to 'keep up with' the drain to the headlamps. The battery will supply the deficit. Unless you are commuting in the winter or doing an all-night rally, a discharge during the run back from the pub (or whatever) should be easily handled by the battery, assuming that your battery is in reasonable nick and charged to start with. The seeming general inability to grasp this point has led to a lot of needless worry and the introduction of alternators, which are (for most purposes) a pointless waste of money and effort.
36/36W bulbs are fine. LED headlamp bulbs tend not to give a decent beam when fitted to pre-war reflectors. Important points are to ensure a decent return wire from as close to the bulb as you can get (don't rely on earth return) and to take the high current away from the c.85-year-old contacts in your switch-panel. These are probably getting pretty tired by now, so will welcome the assistance of relays; these are cheap to buy and simple to wire in.
Joined: Aug 2017 Posts: 308 Threads: 56
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Good evening Alfie.
I am interested in the type of headlamps fitted to your RN. Currently I am preparing a series of articles on A7 lighting and I have found that the early RN's had Lucas R47's fitted with 'Lucas Graves' double filament dipping headlamp bulbs later being changes to the Lucas type 35/32 still fitted with the 'Lucas-Graves' bulbs and both with 'reeded' glasses.
These bulbs are still available but are more usually known as 'Bosch' bulbs. They have a larger diameter metal body and small and larger rectangular lugs (unlike the round pins normally fitted to bulbs), the purpose of these lugs is to ensure that the bulbs are inserted the correct way up to give the dip/main orientation.
The bulbs that have been identified as available would fit the 'scuttle' lamps (raised in an earlier posting) although there is no facility for focussing them.
Regards from Staffordshire - the creative county.
Stuart
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Location: Scottish Borders
I used 36/36 watt headlights with no problems for years. Lots of night driving and very long journeys.
Unless of course your battery's knackered.
Jim
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Location: Auckland, NZ
With 3 brush dynamos low system volts reduces the output so even with standard bulbs balanced if battery somehow gets very low it can be impossible to recover with all the lights connected. If caught far from home can disconnect one lamp. Because of the characteristic some vintage enthusiasts claim more light with low wattage bulbs!
A problem is that many sources state that the dynamo should be adjusted to balance the headlamp load but there is no reference to the associated bulb wattage and the info hard to find in contemporary publications. Owners need be aware of their particular set up.
Original lamps could be focussed so low wattage bulbs were reasonably practicable. Later set ups are often more spread (ie BPF) as required for modern driving. A lot of spread light immediately in front of car is now required to show lane lines and collections of curbstones planted in the roadway
With work and study I often did not have time to attend dynamo troubles; usually worn 3rd brush. Used to run car for weeks without charge, including 60 mile trips home on weekends largely in the dark. Recharged at work, but battery life was not long.....
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Car type:
I'm still confused by the focusing thing. I'm presuming that new A7W reflectors with dedicated APF bulbs are fixed focus and all will be well through lens which have stippled glass and no focusing ability in R47s - i.e. there are no possible adjustments to be made.
But I'm weighing up whether the scuttle lamp system with reasonably good original reflectors can be BETTER than this? (accepting they will be 2' further back!) One just tries the bulb in all three - at night - and picks the best? Surely we must have evidence building up for particular bulbs to ascertain recommendations/experience..?
