stunthanger.com
General control line discussion => Open Forum => Topic started by: Perry Rose on March 27, 2014, 05:13:07 AM
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Has anyone tried the Evolution .60 spark gas engine? Looks like a cure for the old spark engines.
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It's not a true Old Time engine.
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Has anyone tried the Evolution .60 spark gas engine? Looks like a cure for the old spark engines.
Cure? What needs to be cured?
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Has anyone tried the Evolution .60 spark gas engine? Looks like a cure for the old spark engines.
Might work fine but it's not legal for OT stunt ignition because it doesn't use points! I think originally the PAMPA rules allowed any kind of ignition system but that was changed and now the rules state that the primary ignition voltage must be carried through conventional points or something to that effect. Magnetic pick-ups are disallowed.
The purpose of the event is to use at least a semblance of the equipment available in the late 1940's etc. It certainly can be done.
Currently it would seem that the biggest weakness is the availability of good coils. At least that was what I was told recently by the competitors at VSC. There were several coil failures.
I will also state that Frank mcMillan and Jim Lee had nearly perfect runs and instant starts on both flights...some guys make it look easy.
So if someone out there is looking for a cottage industry that will take a lot of time for very little money made...make successful coils for OT ignition! Dale Gleason was heard to say after his coil failure that he wished someone would make and sell reliable coils...That may be a paradox however! LL~ LL~
Randy Cuberly
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Hence the popularity of glow plugs and the hefty bonus for doing it the old way.
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Might work fine but it's not legal for OT stunt ignition because it doesn't use points! I think originally the PAMPA rules allowed any kind of ignition system but that was changed and now the rules state that the primary ignition voltage must be carried through conventional points or something to that effect. Magnetic pick-ups are disallowed.
The purpose of the event is to use at least a semblance of the equipment available in the late 1940's etc. It certainly can be done.
Currently it would seem that the biggest weakness is the availability of good coils. At least that was what I was told recently by the competitors at VSC. There were several coil failures.
I will also state that Frank mcMillan and Jim Lee had nearly perfect runs and instant starts on both flights...some guys make it look easy.
So if someone out there is looking for a cottage industry that will take a lot of time for very little money made...make successful coils for OT ignition! Dale Gleason was heard to say after his coil failure that he wished someone would make and sell reliable coils...That may be a paradox however! LL~ LL~
Randy Cuberly
Coils can be a problem for sure, but still, a sound system and good batteries are very reliable.
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I had one old Aerospark coil that had a wire broken just inside the end cap 10 years ago. I took off the end cap, repaired the wire and have several hundred flights on it now. I have six planes all with ignition engines that have many hours of flying without one coil failure. Knock on wood. Of all the failures that I have had it was always a wire broken or loose points. I learned not to solder the wires but just crimp the ones like to the ground and the points and tie the wires as close to the termination as I can. I also solder the moveable point to the arm as they will come just loose enough to cause problems. That old Aerospark coil that I fixed was one of the larger ones that has about 6700 ohms from primary to secondary and will throw a spark a 1/2". It has been in my Taurus for 10 years without a failure.
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If you have ever taken a coil apart, you will find that the secondary winding has many thousands of turns of "hair wire", so thin that the slightest tension will break it. The layers must be absolutely even, with a layer of very thin "condenser" insulating paper (or plastic) between each layer. In short, you must have an expensive solenoid coil winding machine. There are a few such machines in the USA, but they are not used for our spark coils.
The coils now being made come from China. The reliability problems they are having would demand more interaction between the US suppliers/importers and the Chinese manufacturers. This doesn't seem to be happening.
I also have repaired Modelectric and AeroSpark coils. Vibration breaks the internal wires where they are soldered to the lugs. Also, they are held together with bee's wax, which doesn't hold up to vibration. After my repairs, I seal the housing together with epoxy to prevent further failures.
Floyd
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Jim & FLoyd, I agree with you both, I've also do things like this, but I guess in reality allot of guys don't have the knowledge of ability to do them. When sparkers were all there were, we learned how to do it. Glow as a great boon but it also took some knowledge and practice out of it.
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Hello Floyd,
It seems that you have now come across some of the problems I outlined way back with the Chinese coils. Glad it just isn't me anymore! On the point of winding coils, it can be done. I built a coil winder many years ago and it was modded to provide no tension in the feed wire system. I did wind two coils with this. It took many hours and putting in the interleaves was an absolute pain. I vacuum impregnated the final result with thin epoxy and they have run very well since construction, a few years ago. However I wouldn't be prepared to sell them for a King's ransom! There was so much sweat and tears in that exercise, that I would never do it again!
Regards,
Andrew.
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I bought several of the Modelectric coils when they were about $24.00 apiece and before they quit making them. They have worked well for me although they don't have quite the spark potential of the large Aerospark coils. I wrap the coils in foam rubber and masking tape to keep them from vibration and maybe that is why they have not given me trouble.