Horn operation using steering wheel

[andy-rogers]

I have a MotaLita steering wheel with centre push switch for horn. I wired it up to the horn, fine, but simply attaching it to the horn relay with a cable results in the cable being wrapped around the steering column on full lock. This is going to break the wire. Is there a better/proper way of doing this, such as a sliding switch or radio-remote switch?

[h_m_cumming]

Re: Horn operation using steering wheel

Hi Andy, when I did mine I made up a slipring at the rear of the wheel with a contact finger from the horn push running on it. To make sure you have a good earth to the steering column, as the horn push earths to it, you need to also have some sort of wiper on it to earth.
I'm afraid I don't have a pic of the rear of my wheel but I made the slipring for the rear of it from a piece of plain printed circuit board glued in with the wire from the horn push soldered to it. The wiper you can see mounted on the indicator switch unit then runs to the earth side of the horn relay. You can also just see in the hole where the steering column comes through, the wiper that runs on the column to give it a good earth
Hope that's been of some help.
Hugh.

[danny_nelson]

Re: Horn operation using steering wheel

Andy, Motilata do a boss with a brass ring and a spring loaded button that makes contact on operation as well. Mountney tend to use the method that you have described.

[andy-rogers]

Re: Horn operation using steering wheel

Thanks for the replies. I just bought a (VW) slip ring on EBay, hopefully will be able to fit it. (MotoLita boss seems very expensive). Will presumably need to fit a brush or contact to the slip ring, or 'spring loaded button' as you say Danny. Hugh, how did to make/fit your 'contact finger'?

[h_m_cumming]

Re: Horn operation using steering wheel

Hi Andy, if you look at the pic of the indicator switch block, the metal plate on top with the two red plastic bits is insulated from earth (and all other connections) so I used it to attach a wiper arm made from a piece of spring copper strip I had and then connected it to the earth side of the horn relay, the black wire you see on the other screw.
Thinking about it , the finger could be on the wheel and rubbing on the metal plate!!!!doh. As long as it misses the screw heads.

[andy-rogers]

Re: Horn operation using steering wheel

Thanks hugh. Will have a go when the slip ring arrives. Also came across this link, which gives some ideas.
http://www.mgb-stuff.org.uk/hp.htm#2

[dave_kitson]

Re: Horn operation using steering wheel

Hi Andy
You don't say which model Marlin you have so I don't know what your donor is, but I have a MotoLita wheel on my Cabrio, and have tried Mountney too. The golden rule when buying a steering wheel is to buy the appropriate boss too - in my case to suit a Sierra column.

The Sierra column has two sprung brass buttons which contact with two concentric brass rings on the Sierra wheel. The Mountney boss similarly has two brass rings in it so it is a simple swap. The MotoLita boss is made to take the slip rings from the Sierra wheel, so in this case you need to have kept the steering wheel even if you want to put on an aftermarket item. Both the sprung contacts and the slip rings are easily removed from the Sierra, so they may be adaptable to another column.

Hope that helps! Dave

[andy-rogers]

Re: Horn operation using steering wheel

Thanks Dave - it's a Sportster, and I think it's a Sierra steering column. However, as I didn't build the car I don't have the original wheel. Certainly the MotoLita wheel boss doesn't have any slip ring or sprung contacts in it, so I will have to adapt the one I just bought - when it arrives!

[andy-rogers]

Re: Horn operation using steering wheel

Well, the VW slip ring arrived, but the contact width was only 3mm, so I decided to make one instead. Godd job it didn't cost me much. I made up a ring from a sheel of brass I had - 80mm O/D x 30mm I/D. PLenty of comntact area. Glued it to a ring of mdf which I attached inside the steering wheel. Quite neat. Then discovered it wouldn't fit over the steering lock, so I sawed this off the steering column - it didn;t work anyway.
For the 'brush' I made up a sprung 'pencil' contact using a ballpoint pen tube, and mounted this to the steering column using cable ties. Spring ensures the protruding brass rod it is in contact with slip ring all the way round, but isn't so strong that it'll wear the slip ring or resist the steering wheel turning. Live cable from horn relay attached to pencil brush. Took me a good few hours, but no more tangled cables.