Author Topic: A nice surprise, again. (Read 1415 times)

Brett Buck · « **Reply #1 on:** October 07, 2020, 10:49:43 AM »

Quote from: Lauri Malila on October 07, 2020, 10:20:23 AM

Hi.

It has been mentioned here on many occasions how unpredictable time bombs ringed engines are.

Hey, that's great, since it's so easy, I suppose you will be volunteering to supply micron-quality parts to everyone with an ST46. Then everybody can use their ordinary home diamond-coating kit to toughen up a few parts, and they will be all set. That really stepping up to the plate!

Brett

Reptoid · « **Reply #2 on:** October 07, 2020, 05:59:53 PM »

Quote from: Lauri Malila on October 07, 2020, 11:04:45 AM

Absolutely!😜 Unfortunately ST's need a little more modifications. What would remain from the original is the idea of using the up/down piston movement to spin the prop.
I know I'm being a little provocative, sorry for that.
But seriously Brett, you should not use your past bad experiences with Super Tigre (metallurgical crap) as an example to doom the whole technology. What we have here has nothing in common with that.
Basically, this concept started when the best engine people (who also came up with ABC and AAC-technology decades ago) decided to build an engine with metallurgy best suited for cl aerobatics. So if you study your thermodynamics and the fundamental requirements for engines in this category, you will understand the reasons for the structural decisions.
And if I can do most of it in my spare bedroom (ok, a spare bedroom with 380V supply), it cannot be very difficult. L

I'm curious. Who would those mysterious engine people be? From what I see actually currently available in the real World market nobody is producing a ringed stunt engine. Medusa, Fora/Discovery, Stalker. The ones I have seen are all ABC, or AAC and most are baffle piston design

Brian Hampton · « **Reply #3 on:** October 07, 2020, 06:42:35 PM »

I've never used an ST46 but back in the day I had an Enya 45 model 6001 (the first version with twin rings) and I recall our then current Aussie champion (Peter White) asking me how I got it to run just like his ST46. I had no answer for that because it was bog standard and ran it with straight 75/25 all castor fuel. However after ~2000 flights, which equates to ~200 hours of running, it was starting to take as much as 5 or 6 flicks to start (instead of the usual 1 flick) but once running it was as good as ever. Regardless, I fitted new rings and it was then back to its 1 flick start again.

Much later I went to an ST G51 and it was simply brilliant. Bog standard of course and has never shown any signs of wear. My next ringed stunt engine was the Enya 61CXLRS (the one with a head button, not the later red head ABC) but once again shows no signs of wear.

PerttiMe · « **Reply #4 on:** October 07, 2020, 10:49:07 PM »

Can we draw the conclusion that a ringed engine can be very good, or brilliant, as long as it is designed and built right?

Brett Buck · « **Reply #5 on:** October 07, 2020, 11:09:49 PM »

Quote from: PerttiMe on October 07, 2020, 10:49:07 PM

Can we draw the conclusion that a ringed engine can be very good, or brilliant, as long as it is designed and built right?

Yes. But the number of cases a major manufacturer has successfully managed it are so small as to be negligible, and, more-or-less no competitive engines have been made with rings in the last 30 years, which makes it rather a moot point.

It's just like the ABC vs ABN deal - the good running engines come however they come, there is no such thing as a ringed PA75 or Jett 61, they are AAC. Even if you could perfect the ring fit on an ST46 - you still lose because its still not competitive even if it ran perfectly every time.

Brett

Author Topic: A nice surprise, again. (Read 1415 times)

Lauri Malila

A nice surprise, again.

Brett Buck

Re: A nice surprise, again.

Reptoid

Re: A nice surprise, again.

Brian Hampton

Re: A nice surprise, again.

PerttiMe

Re: A nice surprise, again.

Brett Buck

Re: A nice surprise, again.