Termites Dream

My Feedback: (11)

Gents,
I recently bought two new G-26 Magneto engines for a 101 inch Ziroli B-25 I am building. My question is how to have an ignition cutoff operated from the Tx. I do not want to convert it to EI. My options are:

1. Choke servo. The choke doesnt look like I could easily attach an arm to it for the pushrod but maybe I could weld something on.
2. Buy their kill switch and weld an arm onto that for a ball link?
3. Not have a killswitch.

What do people do for these?

Thanks,
David

All Day Dan

My Feedback: (5)

You can always use carburetor kill from you throttle servo. Dan.

Termites Dream

My Feedback: (11)

Thanks, Dan, might have to do that. I have been flying a Top Flite B25 for 3 years, glow engines, and of course there is no ignition kill on that. We are "supposed" to have ignition kill on gas engines but maybe its not necessary. Throttle servos dont fail often.

Anyone have any other opinions? Since this is a twin, if I did have a stuck throttle on one side the ignition kill might help save the plane. Otherwise I would have to wait for fuel exhaustion and if the engine with the good throttle servo flamed out first, I would lose the plane for sure.

Checklst

Hummmm I fly a G26 mag.......I kill with the throttle trim..........2 other ways use a servo to close the choke or use a servo to flip a switch........the engine has a black wire kill,it just needs to be grounded back to engine ground...........kinda reminds me of back in the day of killing the lawn mower by pushing the flexible ground strip wire(flat piece metal) over onto the plug cap to kill engine. Now both ways require a servo......I would use the black wire and a switch to ground as my kill ......as my choke on the g26 carb would require some work to set up a linkage arm (drill tap ect........to install a servo arm on the choke. The carb/choke on the mag engine is a little different than most.

A single servo and single switch could kill both engines at the same time......never really thought about twin engine setup or flight. Can a single engine provide a few more min flight time? Can my left thumb(rudder) help fly with a single engine flame out? I have a few time used the rudder to save planes when I have had lost aileron servos on one side!!!!!!!!can't say I was smooth with the left thumb, but the planes did make it back to runway and survive to fly another day.

Hope this helps a little

Texastbird

http://www3.towerhobbies.com/cgi-bin...&I=LXJ776&P=ML
Not elegant but they do work.

rc34074

My Feedback: (5)

If you use a servo operated switch to shut off the ignition be sure that it is wired so it grounds the ignition to the engine as Checklst says. Do not have the ignition power always going through the switch to the engine as this can kill the switch itself and cause the switch to either short on or always be open, and either of those is problematic/contrary to your goal.

Ed

The Ghost

Why not just use an ign kill switch such as [link=http://THIS]http://dlenginesaustralia.com/dlshop/electronics/zkill-ignition-kill-switch-magneto-ignitions.html[/link]
Cheers

flyinwalenda

My Feedback: (5)

As mentioned an on-board servo actuating a micro-switch grounding the black coil wire will do it. There also is an electronic switch (receiver controlled on/off switch)that will ground the black coil wire too via the transmitter. If you have any old brushed motor ESC's , they will work too.

Checklst

Hear is a link to the wiring of the G26 Mag........on page 6 is the black wire ground kill switch picture......it looks like a good engine ground is right on the coil bolt that leads to the spark plug cap. The other ground is inside the engine back plate.

A single wire and a 2 pole switch, a single wire from the switch to the ground . Thats why you could wire both engine to the same switch/ground.

http://www.bladehelis.com/prodinfo/F...ine_Manual.pdf

Termites Dream

My Feedback: (11)

Thanks everyone who has posted. I especially like the great planes magneto engine kill switch Texas Tbird recommended. Not sure if I would need 2 of them or whether one would be OK (I assume it would be OK to ground each engine to the other??). A mini servo on that switch should do the trick. This should work better than a servo on each choke.

David

Termites Dream

My Feedback: (11)

Thanks, Checklst. Looks like I can use one switch to connect each black wire to both engine ground. From the look of the commercial systems offered, 20AWG wire should be enough.

DaleD

I just installed the RC-100( http://www.rcatsystems.com/store/ind...&product_id=10 ) from RCATS on my G45. I had the Zenoah Kill Switch sold by 42 Percent Products but it stopped working on the day I maidened the aircraft. I also have another switch which was bought from a UK based retailer through ebayhttp://www.ebay.com/itm/Zenoah-CY-Petrol-Engine-Failsafe-KILL-Switch-/121047822236?pt=UK_ToysGames_RadioControlled_JN&ha sh=item1c2f032f9c

Best of luck to you.

DaleD

flyinwalenda

My Feedback: (5)

When grounding the mag you are essentially grounding out the windings of the coil that makes the electricity . The windings are  rather small  gauge wires and when grounded don't produce much current so the grounding wire can be smaller gauge and the switch can be low current rated..

GBR2

My Feedback: (1)

http://www.rcatsystems.com/rc.php

Get the RC-100X. That will allow the magneto to be grounded via the black wire and controlled by a extra receiver channel.

Termites Dream

My Feedback: (11)

Thanks, gents, the RC-100 would work nicely, not sure if I need 2 of them?? Dont know if its OK to connect the magneto output of one engine to that of the other (and both engine blocks) during engine kill.

CHARLES WINTER

Hi Dave My 2 cents I'm flying an F7F Tigercat for about 2 years now. I am running 2 magneto Fuji 23s (1.5cu). I used the KILL method we used in Giant Scale Racing. We were required to have a manual kill switch located in an area that was RAPIDLY assessable to your crew chief or another dedicated person. I am VERY FRUGAL and use Radio Shack $1.50 toggle switches. I mount them to the rear of the airplane in a SAFE place but readily assessable. I can kill my engines with the standard kill method using a kill switch on my transmitter which closes my carburetor butterfly TIGHT. If there is any difficulty (Hasn't happened yet) like a bad throttle servo or broken throttle push rod I can still kill the engine with the manual kill switch. My normal starting procedure is more like starting a full size airplane. When I'm all fueled up and servo controls check, I ensure both kill switches are in the OFF position. I then PULL my choke Lines (Nyrod indebted in the side of the engine pod) to the choke position. I now move my TX throttle lever a few clicks to open the throttle butterfly. Now I put my starter on the engine and give each engine about a 5 second turn. I am now, VERY MENTALLY (Safety is Paramount) turn each kill switch on and open up the chokes. Both engines are now ready to start. My engines usually start on the first engagement of the starter. Hope this gives you some ideas. Col. Chuck Winter Pic is F-106

Termites Dream

My Feedback: (11)

Charles, beautiful Tigercat. Appreciate the starting advice; I will consider those switches as well. Thank you for your service to our country.

rc74

My Feedback: (6)

I use a Z kill Switch from 42% products for mag engines and a opta kill for batt powered. Your able to kill the engine from the tx. I have had a couple problems over the years where I was glad I could kill the engine by cutting the ele. ( servo went bad, throttle linkage broken/ un-hooked, etc)

karolh

I have been using one of the RCATS RC-100 as a Tx activated ignition switch in my CG Extra / G23 combo for the past 10+ years and it has worked flawlessly.

Karol.

apalsson

My Feedback: (1)

When I used to run magneto engines, I used to have a cheap microswitch activated by a servo to ground out the magneto.
Similar to this:
http://www.jaycar.com.au/productView.asp?ID=SM1038
Cheap, simple and works all the time
You can even have the throttle servo activate it at the "idle cutoff" setting in your radio if you don't want a separate servo

RCER88

My Feedback: (25)

The simplest way is to run a wire to a switch. Activated by servo to kill the mag. That is what I do on my mag engines. It works EVERY time. The switch can be a micro bought from Radio shack. or you can make one out of brass by soldering the wires to two pieces of brass. When the short together it kills the engine.

aghost

My Feedback: (13)

+1 on the RCATS RC-100X. I've been using them for 7 yrs or so, G62 and G38s mag ignition. No problems, always worked.

Termites Dream

My Feedback: (11)

Thanks to everyone for the advice. I will prob either do a micro servo and micro switches from Radio Shack (electronics store) or if I am feeling richer, the RCATS looks like a great solution as well. Since I think need 2 of them, as well as a third to switch my landing lights on and off, the servo solution might save me a few bucks.

GBR2

My Feedback: (1)

If you are going to shut off both engines at the same time, there would be no need for 2 RCATS. One can ground both lines at the same time unless you need the unit right by the engines.