R47 rim fixings

[JonE]

I think I have R47s on the 1929. They have been messed around inside a little, but the removal of the rim involves a sideways movement to disengage the 3 points and thus the front, from the bowl.

This feels much less secure than later lights which have a screw attachment for retaining the rim on the lower part of the bowl.

I intend to put some of the A7W reflectors in which would ideally be silicone sealed to the glass (as the bulb access points are rearwards).

This will make the rim elements heavier, and I'm wondering if this is a good idea with the securing mechanism that seems like it could be disengaged with a long, rough road, for instance!

what have others done with adding the A7W reflector units?

thanks

[AustinWood]

The original reflectors are spring loaded an keep everything in place. The reflectors push against the rims and so keep the bayonet fixing secure.
I fact I find them a bit of a fiddle to remove on my car with no likelihood of detaching inadvertently.

[Stuart Joseph]

Hello Jon. I have been using the method you describe since 1974 with no problems.
However - beware silicon to 'glue' the reflector to the glass as some will turn the silvering black. I use 'Uni Bond' 'one for all' crystal high grab adhesive, available from Wickes. The end product is a much lighter (no pun intended) lamp.

To prevent the rim becoming detached I silver solder a 4BA nut to the inside of the bottom bowl and use a 4BA screw though the rim.

Regards from the creative county - Staffordshire

Stuart

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The original reflectors are spring loaded an keep everything in place. The reflectors push against the rims and so keep the bayonet fixing secure.
I fact I find them a bit of a fiddle to remove on my car with no likelihood of detaching inadvertently.

Hello Austin - your description of the original mounting method is correct but there is a danger of the rim becoming inadvertently detached.

I have recently replaced the rim, glass and reflector for a gentleman's RM whose rim became detached whilst driving and were run over.

Regards from the creative county - Staffordshire

Stuart

[JonE]

thanks both. So I'll be off to google "Uni Bond one for all crystal high grab adhesive"... and the extra nut securing sounds like peace of mind.
I'll hang onto the original reflectors for future re-silvering. Rims seem ok at present.


note - £7.43 from Printerbase online for the large 390g size and free next day delivery!

[Lowespeed]

thanks both. So I'll be off to google "Uni Bond one for all crystal high grab adhesive"... and the extra nut securing sounds like peace of mind.
I'll hang onto the original reflectors for future re-silvering. Rims seem ok at present.

There was also a rubber seal inside the lip of the rim which the glass sealed against. I made mine from 4mm dia solid neoprene round from "Seals & Direct" from Hampshire

[JonE]

The recommeded unibond Crystal works really well - really easy to apply. Thanks Stuart.

I've noticed on the A7W units, the pilot/side lights are not quite in line with the black earth wire, which I understand should be at the top to get correct dipping. So should I have the pilot absolutely at the top so the black earth wire is a few degrees from the vertical, or vice versa?

I'm not sure whether the two filaments need to be at a slight angle to give the right 'line' of light. But it eqully might look odd with the pilots a bit skewiff....!

[Stuart Joseph]

Good morning Jon. When manufactured the orientation of the pilot/main bulb seems somewhat random. When using the 7WS reflectors I position the pilot bulb in the required position (12 o'clock). The bulb holder has sufficient slack in it to position it where you want it (ignoring the locating bump on the bulb holder and slot in the reflector). In order to maintain the dip function as you describe the black earth wire should be at approx tdc.

Regards from the creative county - Staffordshire

Stuart

[JonE]

great, thankyou. the important bit of information there to resolve things is 'ignore the locating bump'... which I will do!