Horn Push Confusion

[jjbunn]

Trying to understand what is missing and non-original in my horn push setup. Please help!

Here's a photo of the underside of the button:



and here is the spider (each foot is spring loaded):



Here's how the spider fits on the steering wheel:



Now the underside of the steering wheel:



And finally the top of the column:



I believe what is missing is something like this:



but can't see how or where it would fit. The horn push is not the same as depicted in the Lotus Europa manuals etc..

Any suggestions most welcome 

[exarkun1178]

That last picture is of a plunger thing.  that is what your missing.  the 4th image shows a hole top right of the bus.  this plunger fits inside that.

[jjbunn]

That last picture is of a plunger thing.  that is what your missing.  the 4th image shows a hole top right of the bus.  this plunger fits inside that.

The more I look, the less sure I am that it needs a plunger like the one I linked. That hole you mention is too far from the axis to work.

I suspect that the copper ring on the underside of the steering wheel has a piece that is broken off. That piece pressed against the copper ring in the steering column, making contact. There was then a wire that was soldered to the wheel's copper ring, which passed through the hole you mentioned, and was attached to the spider, so that when the spider was pressed, the copper ring had a path to earth.

That's my theory, anyway 

[EuropaTC]

I think you could be right on the "broken ring" theory.   Somewhere I have a steering wheel which doesn't use the spring loaded connector to maintain contact, it just uses a bent bit of copper.  If you look at the photo you can see what looks to be a small raised section with a fracture edge. That would tie up very well with the strip of copper that is bent to make contact with the steering column copper ring.

A very crude system but it did seem to work. I'm struggling to remember which wheel it was on, Astrali perhaps ?

Brian

ps - Merry Christmas to all..... Santa's bought me a mota-lita wheel for the Europa   

[jjbunn]

I think you could be right on the "broken ring" theory.   Somewhere I have a steering wheel which doesn't use the spring loaded connector to maintain contact, it just uses a bent bit of copper.  If you look at the photo you can see what looks to be a small raised section with a fracture edge. That would tie up very well with the strip of copper that is bent to make contact with the steering column copper ring.

A very crude system but it did seem to work. I'm struggling to remember which wheel it was on, Astrali perhaps ?

Brian

ps - Merry Christmas to all..... Santa's bought me a mota-lita wheel for the Europa   

Thanks, Brian - I agree it looks like the section between the points marked by your blue rings is missing: probably broken off.

Perhaps I can repair it with some springy brass contact strip.

[EuropaTC]

Hi again,

I found the wheel that I mentioned yesterday and took this photo which shows the arrangement of the connector between the wheel & steering column. It's an Astrali wheel/hub and from the 70s IIRC, certainly it's not a modern wheel.  There is very little stress on the brush/strip connector so I think you'd get away with soldering a strip of copper in place.

Brian

[jjbunn]

Hi again,

I found the wheel that I mentioned yesterday and took this photo which shows the arrangement of the connector between the wheel & steering column. It's an Astrali wheel/hub and from the 70s IIRC, certainly it's not a modern wheel.  There is very little stress on the brush/strip connector so I think you'd get away with soldering a strip of copper in place.

Brian

Brian, this is so very useful: thanks for posting it. Looks like I should be able to fix mine up.

Do you have a photo of how the wire is attached on the other side? That part of the system is not quite clear to me yet.

Julian