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Ignition Switch / Choke Servo Mixed to same Switch. Bad idea?

Old 05-22-2014, 07:42 AM
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CafeenMan
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Default Ignition Switch / Choke Servo Mixed to same Switch. Bad idea?

In another thread the topic of being able to positively kill an engine in flight came up which prompted me to post what I had planned to do with my current project.

The engine is a DLE 55. I have an optically isolated switch on one channel and a choke servo on another.

I set it up on a 3-position switch like this:

Position 1: Ignition Off, Choke Off

Position 2: Ignition On, Choke On (the reason being I figured that when choking the engine I would know the engine is primed when it kicks).

Position 3: Ignition On, Choke Off

I was told this setup is a bad idea and should have the ignition and choke on separate switches. I have plenty of unused switches so that's not an issue. It's just something more to remember the settings of.

So why is my setup bad exactly? The person who told me to rethink it didn't say exactly what's wrong with it but just to ask for experienced advice. So I'm asking.

Thanks.
Old 05-22-2014, 08:11 AM
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raptureboy
 
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I'm not an expert but from the point of redundancy wouldn't you want to be able to kill the engine with the choke if all else failed? If your ign is on and your choke is off in position 2 then how will you kill it? If you make pos 1 ign off choke on then you could flip to 1 to kill it. Just my thoughts. You could just go back to putting ea on a seperate switch.
Old 05-22-2014, 08:17 AM
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CafeenMan
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Either Position 1 or 2 will kill the engine. The engine won't run with the choke on. The choke is on in position 2.
Old 05-22-2014, 08:33 AM
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BarracudaHockey
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I don't see an issue.

If you flip the switch the engine dies.
Old 05-22-2014, 09:12 AM
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raptureboy
 
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yep sometimes I don't see the forest for the trees I don't see a problem, sounds like a good idea as a matter of fact. Some folks just can't handle new ideas I guess.
Old 05-22-2014, 09:31 AM
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CafeenMan
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There was another reply in the other thread right after I posted this. He said that after the first flight of the day full choke is too much and no choke doesn't work so he has his choke servo on a 3-position switch by itself with position 2 being half-choke and it works like a charm for him.
Old 05-22-2014, 09:33 AM
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speedracerntrixie
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I see no issues, some people just want to poo poo an idea just because it's different. I'm running my IBEC off the right side slider on my TX and had people comment it should be on a switch. You should see the looks I get when I tell them that two airplane I have the retracts are operated off the same slider. Sometimes thinking outside the box is frowned upon by the " Experts ".
Old 05-22-2014, 10:07 AM
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All Day Dan
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Caffeen, Why not use the kill switch alone? By the way, which kill switch are you using? Dan.
Old 05-22-2014, 10:14 AM
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Truckracer
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I prefer separate switches simply because it gives me more options. As always, each owner can do as he wishes and that is perfectly OK.
Old 05-22-2014, 11:47 AM
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Bob Pastorello
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Generally speaking, in my half-vast experience of 4 decades, I have found that "good" ideas are those that meet broad acceptance because they are things that don't create problems. The "bad" ideas seem to be those that wreck airframes or damage stuff, hence they get labeled "bad".

One of the "good" ideas that came along once upon a time after programmable radios was the suggestion by a wise and skillful builder/flyer who strongly suggested that I "make all my transmitter setups the same as for switches, functions, directions of "on"/"off", etc. because he rationalized that in a "panic" or stressed-out situation I may "forget" which way something is setup, or worse, which way "off" is....or "up", or "kill", or (fill in the blank).

I ignored him and on my first build after, I programmed flaps where retracts were (or ignition kill, I can't remember), had a in-flight "crisis", and sure enough flipped the wrong switch the wrong way and make a really ugly mess of a lovely expensive gas large scale airplane. It was a hard way to learn that the sage old gentleman was wise in his counsel, and I was foolhardy for disregarding it.

To each their own, as their mood, preferences, and experience dictates, but I sure learned that my mental capacity wasn't sharp enough to remember different switch configuration from one plane to another, particularly as the hangar grew and I was fortunate enough to have several airplanes.

My suggestion to everyone these days is this - make it easy for YOU, always.
Old 05-22-2014, 12:08 PM
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Truckracer
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Originally Posted by Bob Pastorello
Generally speaking, in my half-vast experience of 4 decades, I have found that "good" ideas are those that meet broad acceptance because they are things that don't create problems. The "bad" ideas seem to be those that wreck airframes or damage stuff, hence they get labeled "bad".

One of the "good" ideas that came along once upon a time after programmable radios was the suggestion by a wise and skillful builder/flyer who strongly suggested that I "make all my transmitter setups the same as for switches, functions, directions of "on"/"off", etc. because he rationalized that in a "panic" or stressed-out situation I may "forget" which way something is setup, or worse, which way "off" is....or "up", or "kill", or (fill in the blank).

I ignored him and on my first build after, I programmed flaps where retracts were (or ignition kill, I can't remember), had a in-flight "crisis", and sure enough flipped the wrong switch the wrong way and make a really ugly mess of a lovely expensive gas large scale airplane. It was a hard way to learn that the sage old gentleman was wise in his counsel, and I was foolhardy for disregarding it.

To each their own, as their mood, preferences, and experience dictates, but I sure learned that my mental capacity wasn't sharp enough to remember different switch configuration from one plane to another, particularly as the hangar grew and I was fortunate enough to have several airplanes.

My suggestion to everyone these days is this - make it easy for YOU, always.
I always suggest standard radio configurations and have made those suggestions in various forums and in local conversations many times. But, and this is a big but, these days I find more rejection of what I would call conventional wisdom, or wisdom gained through experience. When asked I explain why I am doing what I am doing and explain the logic behind it. Many times I'm just passing on what I leaned from someone older and wiser than myself and how it really is a good way of doing things. If the person asking for the advice chooses not to use that advice or outright rejects it, I'm OK with that and just walk or go away. It took awhile to learn not to care!
Old 05-22-2014, 12:11 PM
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BarracudaHockey
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Originally Posted by CafeenMan
There was another reply in the other thread right after I posted this. He said that after the first flight of the day full choke is too much and no choke doesn't work so he has his choke servo on a 3-position switch by itself with position 2 being half-choke and it works like a charm for him.
Hmm....most of my engines will pop with the choke on and run with it off. I have nothing with a proportional (or even servo activated for that matter) choke and I have a pile of gas planes.
Old 05-22-2014, 01:50 PM
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Truckracer
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Originally Posted by BarracudaHockey
Hmm....most of my engines will pop with the choke on and run with it off. I have nothing with a proportional (or even servo activated for that matter) choke and I have a pile of gas planes.
I think the OP was referring to my post in another thread and I wasn't quoted quite right. Here is the text of the original post. I hope it clarifies things a bit.

>>>> I have choke and ignition on separate switches. Frankly, I couldn't imagine any combination of positions that would make me want to have both functions on one switch. On one of my engines, the idle is extremely lean (normal for this engine) and the engine will not transition to full throttle until it warms up a bit after the first start of the day. I use the middle position of a 3 position switch to just half open the choke during this warm up period. Similarly, some years ago I had an engine that tended to vapor lock (heat soak) the carb when the engine sat a bit after being run on a hot day. The half open, middle position on choke worked well as a start aid when full choke would have been too much and you could crank all day w/o choke.

[COLOR=#000000]The point here being that two switches gives you options that a single switch doesn't allow.
Old 05-22-2014, 03:14 PM
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acerc
 
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I have to say Cafeenman, I like your idea. Well enough to use it. I, as others, like to keep all controls the same for all models. But when getting into 8-10-12 channels it can be a bit daunting to maintain the same orientation with the 2 and 3 positioning switches that come into play. Your idea would eliminate one of those, very cool.
Old 05-22-2014, 06:23 PM
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CafeenMan
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Bob - I agree with you that having a standard way of doing things is very important. However, I apparently have been for years using all my switches backward from the norm. That didn't matter until I wanted help with my helis and the heli guys kept telling me my switches worked backward. Since I was new to helis I decided to go with their way of doing things before it became a habit for me.

But as far as things go I try to always have the same things work the same way so I don't have to remember more than necessary. Slide switches are always off toward the front of the plane. Push/Pull switches are always push on so if it gets bumped the radio isn't turned off. Worse thing that can happen is I bump it at home and drain the batteries.

Anyway, I have a lot of things I do like that. I think it's really important.

This plane, for example, has a lot of turnbuckles. I set every one of them up so the standard thread was on the servo and the left-hand thread was the other end. The tail bracing and cabane bracing is also turnbuckle and I set the standard thread on the fuselage and fin and the left-hand on the stabilizer.

Any time something new like that comes up I try to think ahead and make a rule on the spot. Sometimes I'll find once I start using the thing for the first time the rule is backward and I'll go back and change everything so it's right instead of having to make everything in the future wrong to meet the same standard.

========================

All Day Dan - It's an rcexl switch: http://www.valleyviewrc.com/estore/r...-with-bec.html

========================

Truckracer - Sorry if I didn't express your point accurately. I was just trying to say that it seemed people had good reason to use other setups than my idea other than just not liking different ideas.

========================

acerc - When I don't fly a plane for a while I can't remember anything about it. I was trying to take off one of my stiks one time with my ailerons reflexed. All I could do was high speed runs down the field. The reflex wasn't much and I couldn't see it from where I was. I have a small notebook that holds half-size sheets of paper that I use for a lot of shop stuff. I think I'm going to get another one for my planes and start keeping details of each plane so I know what all the settings are and just as important WHY they are. Half the time when I figure out what a setting is I don't remember what I used it for.
Old 05-22-2014, 06:24 PM
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BobH
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Generally if you fully choke an engine such that it's soaking wet, you can release the choke entirely and the engine will run. I say this with about a gazillion years in the small engine industry and the hobby.
So, Position 2 should be Choke on Ignition off. Position 3 choke off, ignition on.
ANY TIME you have Ignition enacted you have the possibility of the engine roaring to life. Hence my sequence preference.
Old 05-22-2014, 06:33 PM
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CafeenMan
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It won't keep running though, right? I expect it to run for a couple seconds and die. My thinking is that if I don't have the ignition on I won't know when to turn the choke off - maybe too soon and not enough fuel or too late and the engine is flooded. If the ignition is on then the engine will pop and then I'll know I can turn the choke off and the engine should start up. I'm not trying to argue with you - again, I'm new to gas. I'm just explaining my reasoning behind this.

It should probably go ahead and separate the choke from the ignition so I can play around with it in different configurations until I find what makes it easiest to start the engine.
Old 05-22-2014, 06:47 PM
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BobH
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It won't keep running for long but long enough if you aren't careful with your fingers etc.
If you flood the engine it won't stay flooded long. I prefer to use a starter. Doing so keeps my hands safe and a flooded engine starts pretty easily. You can hand prop of course and many do.
Your suggestion of doing something different is a good one.
Old 05-22-2014, 06:52 PM
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CafeenMan
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I think a starter is definitely in my future. A few weeks ago I was starting a DLE 35 on my test stand and apparently didn't have the throttle open enough and wasn't choking enough (which I read about later). My shoulder was sore for days.

A "big" plane for me is anything over .45 size. Normal for me is .15 to .40. I've been doing this for years but always glow.
Old 05-22-2014, 07:14 PM
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All Day Dan
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Cafeen, use this one. It's the only one that gives you conductive and radiated isolation. None of the others provide both.
https://www.smart-fly.com/Products/I...n/ignition.htm
Dan.
Old 05-22-2014, 09:41 PM
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CafeenMan
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Dan - is there something wrong with the switch I already have? Mass failures or something?
Old 05-23-2014, 03:34 AM
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I think that EVERYONE is right - it is just a matter of personal opinion and taste.

That being said - I use a manual choke on start up in the morning. After the first two minutes I do not use the choke for the rest of the day - so why have a dedicated servo and channel assigned??

As for the Kill Switch - When I want to Stop the engine - I want to 'KEEP IT SIMPLE' A simple 'On - OFF' switch works for me. That way there is less chance of error in a 'Heated' moment.


When All is said and done - as alway it is a personal choice - and if it works for you - Go For It!

Happy Landings!
Old 05-23-2014, 03:49 AM
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Originally Posted by CafeenMan
Dan - is there something wrong with the switch I already have? Mass failures or something?
No no no.

I have them on numerous planes for hundreds of flights, they work fine.
Old 05-23-2014, 05:01 AM
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ahicks
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CafeenMan, going back to your original post, I don't see a darn thing wrong with it.

BTW, I choke with ign. on, until it pops once or twice, then flip it off as well. MANY others do the same thing. Don't think twice of it. Not sure I'd ever do the choke with my radio, but darn sure not going to try and convince somebody else they should not? It's your call!

Bunch of old guys/experience around here. Been doing stuff "their way" for a long time. Doing something differently sometimes makes them crazy. Like you've demonstrated well in this post, when you run across something different, you listen and ask questions. Sometimes you learn something new! If you care for the logic, fine, otherwise....
Old 05-23-2014, 06:20 AM
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All Day Dan
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Cafeen, Here is a quote from Futaba's website.

Guidelines for setting up gasoline engine models. All ignition equipment, including an electronic kill switch, must be mounted at least 12", and preferably 14", away from all radio equipment, including throttle servos, etc. Ignition kill switch should always be on opposite side of fuselage from radio kill switch. All pushrods going to anything related to the engine must be non-conductive (just nonmetal clevises is not sufficient).

The Smart Fly switch provides more isolation and the other kind provides less. For $20 you can get more. A wise investment. Dan.

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