Novel switch solution?

[wibblywobbly]

During one of my mad moments I started thinking about how to do away with having to mount switches on tanks. The current (excuse the pun) way of doing it is:

Lipo - Junk the switch, it needs to be heavy duty to cope with the load, and open the tank to connect/disconnect the battery plug.
Nimh - Either a switch inside the hull, so open the tank to switch it on/off, or external which isn't always convenient when installing aftermarket boards, scratch building.

Does anyone use any other means? I am thinking a socketed plug disguised as a crate that simply plugs into the hull to complete the circuit (this would work for Lipo's if Deans plugs etc were used), or a reed switch activated by a magnet inside a crate, or hatch. My ideal solution would be a switch that was activated/deactivated simply by waving a magnet over the hull above where the switch was located. A quick search of Google didn't find anything that would do the job.

There must be a neat way to do away with switches, but has anyone found one?

[RobW]

The reed switch idea could work if you leave the magnet on the hull, maybe in a storage box?

Alternatively I've seen bathroom switches that you touch (no moving parts) to turn the lights on & off. No idea what they're called though.

The main problem with removing the physical switches is stuff going live by accident. I'd still want a proper air gap switch somewhere for transit or longer periods sat on a bench.

[dgsselkirk]

Most of us open a hatch....

You can usually get side by side small switches. I use mine for power and smoke.

[wibblywobbly]

I'm thinking a magnetic reed switch that is defaulted to open. That way the circuit is never live until a magnet is applied to the switch. Have a crate with a small neodyne magnet on the bottom. Stick the crate on the hull and the tank is switched on as the magnet activates the switch. When finished simply take the crate off and the switch goes to off again.

If the tank is left switched on it isn't really a problem, I've done it with some of mine, left them on for days. It will drain the battery eventually but there are no ill effects. Some boards are permanently live, one example is the Clark board. It has the option to plug the battery in seperately to the switch. Switch the tank off and it stops the tank running, but the battery is still connected and the circuits are still carrying current.

One magnetic crate and four tanks means that only one could ever be left switched on by accident.

[hawkeye3guns]

Hi wibbly
You could use 2 reed switches and a relay , swipe the magnet over the first switch and it energises the relay , which switches the main power on and by running a feed of the main power back to the relay coil it also then holds the relay energized. (This gives you a failsafe because if the battery supply runs low the coil of the relay drops off and hence kills the main power)
To switch off normally you just swipe the magnet over the second reed switch which kills the relay coil and hence switches off the main power.
One advantage of this circuit is the magnet does not stay on the model so cannot be knocked off during maneuvers and accidently switching off the tank.
Second advantage is the relay is switching all the power so less chance of arcing or an inadequate switch failing and again causing problems.
Denzil

[wibblywobbly]

Hi Denzil

What you have said makes perfect sense, and there was only one thing that exploring the idea. I figured that a relay could handle the power that a reed switch doesn't but I will openly admit that I haven't got a clue about how to wire up the circuit or which components would do the job.

If there is any way that you could post up a circuit diagram (or pm/email one) I would be rather grateful, it sounds like it is just the solution that I am looking for.

If I can build something that works, I'll post up a 'how to'.

Rob

[hawkeye3guns]

Hi mate
I'm working away at the moment on sea trials I should be home about the 14th Dec.
I will draw the circuit up and sent it to you. Its very simple and easy to make
Denzil

[wibblywobbly]

You are a star, no rush.

[hawkeye3guns]

Hi wibbly
here is the circuit drawing you requested. Hope you can see its a jpeg drawing and as I said its very simple.
All the pits are available from maplins or any other source. ( I priced the bits on Flee bay and they come to about £4.
Denzil

[wibblywobbly]

Thanks for that Denzil, once I have got some free time I will give it a go, if only for the hell of it. One question, which relay do you suggest?

Many thanks

Rob