New switch required

[cymaz]

Went to fly my big DH Gipsy Moth yesterday but didn't in the end. On the engine run up and taxi the engine kept stopping and losing Rx. Checked the batteries..all good. Turned it off then on, everything worked again ( not, everything was fine ! ). I figure it has to be the switch for the Rx battery.

I've looked at some 50 A toggle switches. Has anyone had experience with a toggle switch / charge port setup? Which would they recommend.

 

Anyone used one of THESE ? If so what did you think of it.?

Edited By cymaz on 03/09/2017 08:24:42

[Frank Skilbeck]

Have you considered an electronic type switch, I use the Multiplex ones in my larger models, but there are other types available. Disadvantage of an electronic switch is that they draw a very small current when off, so you need to unplug the battery at the end of the days flying.

Note if you are using standard Rx plugs to connect to the receiver these are rated at 6A.

[cymaz]

Thanks Frank. When I get the old switch out I will take it apart to see if there is anything obvious.

[trebor]

The last switch I fitted was a 3 way double pole toggle switch from RS components, no problems so far and far cheaper than the other rubbish. Just solder on the connections you need.

[flight1]

Get this all in one isolator switch for proven reliability , can get here via ebay i think for a bit more money

[Frank Skilbeck]

Flight 1, is that the correct link? that is for an isolator to allow your ignition unit to be run from the receiver battery via the receiver, not a receiver power switch.

Edited By Frank Skilbeck on 03/09/2017 10:20:51

[flight1]

eer silly me that is the ignition battery switch as you say frank always read the opening Q properly

For Rx switch these are the business

and these from tech aero

[Phil 9]

if your willing to do your own wiring then you can use pretty much any style of switch you like. There are some very high quality military grade locking toggle switches available for example and they are low in price.

but most modellers (me included) tend to pay a premium for a pre wired switch harness with a fancy mounting plate.

[Former Member]

[This posting has been removed]

[cymaz]

OH HELL....HOW LUCKY  I WAS  ?! 

PLEASE, PLEASE CHECK YOUR SWITCHES IF YOU HAVE THIS TYPE...NOW

What would have happened if that had broken in the air....I dread to think

Edited By cymaz on 03/09/2017 11:42:06

Edited By cymaz on 03/09/2017 11:42:43

[Phil 9]

cymaz your link is to a JR switch the colour of the wires on yours suggest it is a non branded budget copy

[cymaz]

The problem may be the same. It's the same construction. It only takes a couple of minutes to lever off the back, make sure the wires are attached onto the board. Either by hot glue. I've just taken the second switch out of the plane and found hardly any glue holding the wires tight and stopping them pulling off the board. I have now filled the back of the switch plate with epoxy and left to set....after checking the solder joints.

[Peter Christy]

I've always used the JR heavy duty switch harnesses (JRPA001) in everything above tiny models. Its the one with a separate charge lead, not the one with a socket built into the switch. Unfortunately, they appear to be no longer available.

I've still got a few Noble 4-pole change over switches left. These were always reckoned to be the "best of the best", and the poles could be paralleled up for even greater security. Sadly again, these are no longer made, but if you want one, I have one. You will have to solder it up yourself, though....

--

Pete

[cymaz]

Posted by Phil 9 on 03/09/2017 12:04:50:

cymaz your link is to a JR switch the colour of the wires on yours suggest it is a non branded budget copy

Different switch Name..different switch board layout. Same potential failure

Edited By cymaz on 03/09/2017 12:37:21

[cymaz]

Thanks Peter C...my soldering skills leave a lot to be desired . I probably will go for a switch that has crimped leads and mechanically fixed on the board. Hope everyone is checking the backs of their switches

[Rich too]

That's why I use two switches and batteries mostly. I use these now...https://fromeco-scale-avionics-llc.myshopify.com/products/wolverine-switch

[cymaz]

I like the build quality of ...Here...

Edited By cymaz on 03/09/2017 13:08:13

[Mike T]

Posted by cymaz on 03/09/2017 12:36:30:

... Same potential failure

I'm struggling to see what that is, TBH. The negative wires appear to be firmly soldered to the track and the (redundant) signal wire likewise, to provide a little additional strain relief. The +ve wire is soldered between the pole contacts and the gap between them is bridged to provide switching redundancy (though you'll only find out that one pole has failed if the other one does...)

I used to buy the heavy duty locking toggle switches from Terry at SM. Of course, they attracted their 'sledgers' as well, with people claiming that engine vibration would cause the toggle to jump over the lock!! It's a pity they can't be got any more.

The machining on the RCWorld switches is nice (polished/anodised alloy being de rigeur for big petrol 3D type planes), but the switch underneath appears to be the same DPST toggle that can be had from Maplins, RS, etc for a quid or so.

[cymaz]

Posted by Mike T on 03/09/2017 14:24:54:

Posted by cymaz on 03/09/2017 12:36:30:

... Same potential failure

I'm struggling to see what that is, TBH. The negative wires appear to be firmly soldered to the track and the (redundant) signal wire likewise, to provide a little additional strain relief. The +ve wire is soldered between the pole contacts and the gap between them is bridged to provide switching redundancy (though you'll only find out that one pole has failed if the other one does...)

Having such a serious failure with a switch, that if had happened in the air, would have led to goodness know what. I am a bit jumpy about leads coming off a switch because of little or no mechanical fixing, only relying on the solder to keep the wire on the board. Look inside a cdi box that runs your rc petrol engine and it's full of epoxy. We all know what happens to metal with constant bending. I make no apologies for bringing it up.

The other switch on my plane had perfectly good solder joins but there was no more than a couple of dabs of hot glue fixing the wire to the board. This has now been filled with epoxy. Any one had a sudden loss of control or signal failure? Makes me wonder.

[Peter Christy]

I was warned about using those switches with built in charge sockets many years ago, and now I know why! The switches themselves are fine. The weak spot is the PCB and the way the wires can easily be damaged by the back of the case. The switches with the separate charge lead do not have a PCB in them. The wires are soldered straight onto the back of the switch, with the poles paralleled up for extra security. The case the acts solely as a strain relief.

Never had one of those fail - yet!

--

Pete

[cymaz]

Before

After a good coating of epoxy. Better now..

[Gary Manuel]

I think there's more to worry about what's the other side of the circuit board than the epoxy on top Cymaz.

Those switches use the type of slider contacts that were designed for transistor radios. Not really designed to take the current, vibration or oil infestation that we expose them to. Much better to use toggle switches in my opinion.

In addition to some of the switches already mentioned, AGM do a nice range of switches / fuel dots.

[Mike T]

Fair enough if you're using the charge port type switch with a pcb. I have one, but just use it for bench work as it's too bulky for use on a plane. I usually use just the type with 2 or 3 leads and I've never know any switch of that type to be 'potted'. Strain reilief on them (if any) is a knot in the cable to stop it pulling through the case.

Incidentally, it's always been my experience that "heavy duty" usually refers to the case work and wiring - the guts of the switch is usually the same for both 'normal' and HD.

[cymaz]

Put the above switch in the plane...gave it some tugging. No problem

[Bob Cotsford]

I had one of those switches with a built-in charge socket in the Jabberwok - it managed to switch off in mid-air. I suspect that there wasn't enough of a detent to stop it vibrating off - just my guess as it was off at the crash site and the radio worked when switched back on.