So Ive done a couple of these now with orig. mags but would like to explore poss. going EI to lose some weight. I could always hand start the mag 33's easily so it's purely a weight and cosmetic thing. I assume something like an RCXL ignition unit? I don't know where to get an EI prop hub made or really how to setup the sensor etc. Can anyone offer any help with this?
Thanks!!!

Here's a good place to get the ignition: www.rcextremepower.net. The prop hub and sensor mount you could possibly find here:

http://jagengines.com/
www.lambertsrc.com
www.carrprecision.com

There was another good one called Whacker Engines, but I believe he quit doing it and can't find anything about him on a web search.

By the way, those Homelite 33cc engines are quite good.

That's about it!
AV8TOR

Thanks! I'll check those links out. If I can't get the parts, I guess it will stay a mag. engine.

I don't know, with the cost of an electronic ignition, short battery life, and fragile hall sensors, you would think that someone would have a smaller, lighter version of the standard magneto.

Anyone ever hear of one?

PC

No, never heard of any. But the electronic igntiion systems are far from fragile and the cost is quite reasonable I think at around $45.00 now. I personally have had a problem with Nimh battery life, but I abuse them with very high ambient temperatures where they are stored, and I don't use or cycle them often enough. I switched to Nicads on some of my equipment and have had somewhat better luck. Now I have a few running on regulators with Lipoly batts which I take out and keep in a safe, temp controlled place when not in use. The ultimate is the A123 battery packs which I am going to switch all my equipment to as soon as I can. But this is all just as true with my flight packs as it is with the ignition battery packs so the point is moot as far as electronic ignition is concerned. Many people are now running an IBEC and running their electronic ignitions on the same battery as used for the flight pack; hence only one battery in the plane. As far as Hall sensors, what usually kills them is someone playing around with the system and activating it while not grounded. That will kill a Hall sensor. I have had only one, true, "natural causes" Hall Effect death in the last 8 years, and I have numerous planes and lots of engines.

The problem with creating a lightweight magneto is that magnets and the iron core coil needed will always weigh too much. Granted, with todays modern rare earth magnets a lighter weight mag could be made, but with a better solution, (electronic ignition) available for only 45 bucks, I don't think anyone is going to bother to make one. Besides the weight savings, electronic ignition can give you more power, and easier starting. It's way worth it to me....

AV8TOR

I've run a C&H MK-I Syncrospark (made in 1997) CDI for years on a Saito FA150 burning methanol. It has survived numerous crashes including one straight in from altitude @ WOT. The engine was entirely buried W/only the muffler sticking out of the ground.

I’m still running the original Hall sensor & module.

To the people that don't have problems with hall sensors, congratulations, you are better than I.


I may have mentioned this before, but I work as a quality engineer for a small company that makes automotive ignition systems.

Specifically I investigate failed ignition systems. Hall sensors are nice but they do fail frequently. (approximately 80% of electrical failures on our Ford distributors equipped will hall pickups)
A good magnetic reluctor is much tougher and will fire reliably at hand crank speeds.


I had a pair of rcexl ignition systems purchased from hobby king two years ago. I killed the first hall sensor with a probable grounding issue. The second unit I got working for about 5 min before the entire unit quit.

Then I started converting parts from work, mostly as research. Since this is automotive not dedicated rc stuff, the systems weigh in about 2x-3x heavier than the rcexl setup.
They seem to be pretty rugged, and since it's part of the research program it doesn't cost me anything. However depending on what units I'm using and the RPM the engine is turning, power consumption can be high.( IE dedicated LiPo ignition battery.) After some research, I found the dwell control in the ignition module, so it may be possible to reduce the power factor a bit.

I also Googled miniature magnetos and there was enough information available to raise the possibility of modifying an existing ignition coil from work to magneto service. I've identified a couple of good candidates for testing.

Even with the magnetic core and coil windings weight would be much less than OE flywheel and probably less than rcexl system with dedicated LiPo.

Worst case, would be the creation of a miniature alternator for gas engines reducing the size of flight batteries required for extended operation.

I might get a chance to work on it more after the snow starts melting.

PC

Maybe your quality control is lacking.

Oh Ford, never mind.

For your interest: http://www.sullivanproducts.com/GenesysMainFrame.htm

And sorry, but he does have a point. Ford electronics are pretty well known to be the worst in the industry.

Good luck with your experiments and keep us updated.

AV8TOR

In addition, once again, I have only had one true Hall Sensor failure in the last 8 or 10 years, and I think truth be known, gas was dripping on it from a leaky front seal and that is actually what killed it. I only had one other ignition problem with RCEXL, and that was a twin cylinder unit from Hobby King. It would start the engine after a terrible amount of fussing when the engine was cold, and then would work fine until you had another dead cold start. Using 6 volts instead of 4.8 made it work just fine, (a trick I learned from Bill at CH Ignitions), but I wasn't comfortable with it having a problem and sent it back for a replacement. There are just too many of use running the RCEXL ignitions successfully now to consider that it is overly problematic other than the # 4 unit with it's really stupid advance curve.

If you want to experiment, by all means feel free but the RCEXL and the CH Ignition units work great. The other Hobby King units they sell are questionable and have had purported problems and early failure rates, but the RCEXL and CH Ignition units are great.

I have a somewhat higher than normal experience level with these small gas engines and ignitions, both because I have a fleet of 8 or more flying gas planes, and because I build and sell conversion engines to people.

AV8TOR

Every one of my Saito engines has CH Ignitions CDI firing off 15% Cool Poweer glow fuel. I have never had a failure of any kind other than oil soaked plugs after storage & one twin module that was defective in one spark lead when I received it.

2 of those sytems are over 16 years old.

Ditto on the LiPo4/A123 batterey packs. All of my planes are now converted. These cells do not self discharge. They deliver more amps than you can use. I make my own packs. I buy the cells here: http://www.batteryspace.com/LiFePO4-...gle-Cells.aspx No power distribution boxes or regulators are needed or desireable.

I typically use dual packs, and dual switches. I run my ignitions with opto coupled BECs. They are RCEXL brand and are cheap. You can get these from Valley View. This is a big safety advantage since you have a kill switch on the TX and an LED to visually confirm that the ignition is on or off.

Hang time Hobbies webpage will explain how to wire the charge ports. They show you how to charge through you regular charge port switch while balancing the cells. You can do this with a charging plug for your old LiPo4 capable charger.

For me it is peace of mind to know I have a bullet proof power system. I can not see myself using any other type batterey for the foreseable future.

Personally, I love having mags on the converted engines. It keeps things so simple; no extra batteries! The added flywheel weight should contribute to a smooth. low idle as well. My mag ignition engines hand start as easily as my CDI equipped ones. I agree that CH ign is the best of the "magic box" type, but I have had zero problems with the cheap Chinese offerings so far.