Re-Honing Piston Liner (Ringed)
08-11-2022, 09:16 AM
#51
Yes, its happening right now and not just rc engines but everything else as well. BTW, if you are not sure what the system we all find ourselves in its called turbo supercharged capitalism and its main driving proponent is human greed.
I see everyone posting here doesn't like it when I explain it as is?
I see everyone posting here doesn't like it when I explain it as is?
08-11-2022, 09:34 AM
#52
Thread Starter
Oh, if you trust yourself enough, the entire break-in can be done while flying, and if you know what you're doing, it is THE best way because everything beds in with the temperatures, but more important, the cooling airflow, to which the engine is exposed in flight.
A quick 15 minute run-up on the bench if you trust yourself less, then the remaining break in in the air is also OK.
It is not about the bench or the plane, I merely wanted to bring attention to that the engine basically needs a full break in period, because the ring is the determining factor for that.
FWIW: for ringed engines, the best way to break it in is short burst of full throttle (like the 10~15 seconds it takes to get airborne and say, a 100 ft altitude) then throttle back as far as safely possible for a short duration, then fly and vary throttle a lot between full and minimum. You want the gas pressure against the ring to press it against the liner (that is what seats it properly) but on a new ring this generates quite a bit of local heat. Since the heat is local, you can NOT judge this heat by checking the engine temperature. So you have to let it cool down for about the same duration by running low power. As the process progresses, you can hold longer periods of full throttle because as the ring wears in, it gets smoother and friction and heat get less and less. 8 t 10 15 minute flights should do the trick completely. After that, the ring has not yet fully seated (that takes in total about 10 hours) but it is by now smooth enough not to burn up from continuous full throttle.
A quick 15 minute run-up on the bench if you trust yourself less, then the remaining break in in the air is also OK.
It is not about the bench or the plane, I merely wanted to bring attention to that the engine basically needs a full break in period, because the ring is the determining factor for that.
FWIW: for ringed engines, the best way to break it in is short burst of full throttle (like the 10~15 seconds it takes to get airborne and say, a 100 ft altitude) then throttle back as far as safely possible for a short duration, then fly and vary throttle a lot between full and minimum. You want the gas pressure against the ring to press it against the liner (that is what seats it properly) but on a new ring this generates quite a bit of local heat. Since the heat is local, you can NOT judge this heat by checking the engine temperature. So you have to let it cool down for about the same duration by running low power. As the process progresses, you can hold longer periods of full throttle because as the ring wears in, it gets smoother and friction and heat get less and less. 8 t 10 15 minute flights should do the trick completely. After that, the ring has not yet fully seated (that takes in total about 10 hours) but it is by now smooth enough not to burn up from continuous full throttle.
LolYes, I agree with the cooling during flying. I just finished running two tanks through this engine. However, thanks for the tip on throttle settings in the air.
I wasn't going to run at full power when airborne but only 3/4 max. This is what I have been doing in the past for the first 2-3 sorties. I guess i'm not correct according to what you say therefore this weekend I'll go Max Throttle for the short bursts.
Last edited by Eastflight; 08-11-2022 at 09:49 AM.
08-11-2022, 12:15 PM
#55
Thread Starter
08-11-2022, 12:19 PM
#56
Not so much name-calling but a pretty accurate description of his character. Hopefully he will come face to face with someone he has bilked. As they say Karma can be a BXXch. To bad there is no way to warn potential buyers about this guy like I did with the video of the thief at the Toledo show that I posted on this site. The guy obviously has the same moral compass as this fellow had.
Last edited by Propworn; 08-11-2022 at 12:39 PM.
08-11-2022, 12:56 PM
#57
08-11-2022, 01:15 PM
#58
Absolutely I trust myself - except when there's another slice of cake going for grabs!! Lol
Yes, I agree with the cooling during flying. I just finished running two tanks through this engine. However, thanks for the tip on throttle settings in the air.
I wasn't going to run at full power when airborne but only 3/4 max. This is what I have been doing in the past for the first 2-3 sorties. I guess i'm not correct according to what you say therefore this weekend I'll go Max Throttle for the short bursts.
LolYes, I agree with the cooling during flying. I just finished running two tanks through this engine. However, thanks for the tip on throttle settings in the air.
I wasn't going to run at full power when airborne but only 3/4 max. This is what I have been doing in the past for the first 2-3 sorties. I guess i'm not correct according to what you say therefore this weekend I'll go Max Throttle for the short bursts.
This method also works with motorcycles and such, but whether it can be applied depends on the rest of the rebuild, what has been done/repaired/replaced on the rest of the engine or the bike, because it has to be done under load, or in other words, riding the bike and giving it a few bursts of FULL acceleration. I mean, if you're not sure of how well the brakes work, I really would not recommend it
Mind you, this is NOT "vital" or in any way dealbreaking, but the engines I broke in using this method usually showed excellent pistonseal once the full break in was done (10 hours of runtime), better than engines that spent a couple of hours tuckering away with a fat mixture.
Just a thought...
EDIT; just an afterthought: do NOT use that "full burst method" when breaking in a Saito... they do not really like that due to the unbushed conrod.
Last edited by 1967brutus; 08-11-2022 at 06:48 PM.
08-11-2022, 01:29 PM
#59
Thread Starter
I would like to say that when I started this tread, I was not aware of honing on model engines but I think the question has been answered thanks to the positive feedback and advise given by the members of this forum.
It is much appreciated and I've learnt once again something new in this wonderful hobby of ours however, sadly I feel that the conversation is now rapidly going down a 'slippery slope'.
So for that reason I'll sign off on this thread until I need some help/advise on another matter. No doubt it will be soon.
Again, Many thanks & cheers for now !!
It is much appreciated and I've learnt once again something new in this wonderful hobby of ours however, sadly I feel that the conversation is now rapidly going down a 'slippery slope'.
So for that reason I'll sign off on this thread until I need some help/advise on another matter. No doubt it will be soon.
Again, Many thanks & cheers for now !!
08-13-2022, 11:13 AM
#62
Thread Starter
HI folks, Just wanted to conclude on how the flying went today with the airborne break-in of the new piston ring and honed liner.
I managed to get about 3 hours of actual flying time on the engine. Obviously ran it it cautiously. The first 3 tanks (12oz) with a caster mix 5% and then resumed with my usual 12% thereafter. The low end needle didn't need much tweeking (just a 1/8 turn did the job).
All went well and she's opening up nicely.
Cheers for now !!
I managed to get about 3 hours of actual flying time on the engine. Obviously ran it it cautiously. The first 3 tanks (12oz) with a caster mix 5% and then resumed with my usual 12% thereafter. The low end needle didn't need much tweeking (just a 1/8 turn did the job).
All went well and she's opening up nicely.
Cheers for now !!
08-13-2022, 12:37 PM
#63
HI folks, Just wanted to conclude on how the flying went today with the airborne break-in of the new piston ring and honed liner.
I managed to get about 3 hours of actual flying time on the engine. Obviously ran it it cautiously. The first 3 tanks (12oz) with a caster mix 5% and then resumed with my usual 12% thereafter. The low end needle didn't need much tweeking (just a 1/8 turn did the job).
All went well and she's opening up nicely.
Cheers for now !!
I managed to get about 3 hours of actual flying time on the engine. Obviously ran it it cautiously. The first 3 tanks (12oz) with a caster mix 5% and then resumed with my usual 12% thereafter. The low end needle didn't need much tweeking (just a 1/8 turn did the job).
All went well and she's opening up nicely.
Cheers for now !!
Good to hear the engine ended up being well!
08-13-2022, 12:57 PM
#64
Thread Starter
I even had a chance to fly another plane a couple of times.
There was also a BBQ at lunchtime laid on, so no excuse for being tired.
However, it was a damn hot day today and not a cloud in the sky
!!
Last edited by Eastflight; 08-13-2022 at 02:02 PM.
08-13-2022, 01:37 PM
#65
Thread cleaned up, drop the politics and bickering, you've been warned.
Posts have been deleted, posts that had snippy replies or quoted a deleted post have also been deleted.
There appears to be some good discussion in this thread so keep it on topic or move along please.
Posts have been deleted, posts that had snippy replies or quoted a deleted post have also been deleted.
There appears to be some good discussion in this thread so keep it on topic or move along please.
08-13-2022, 02:00 PM
#66
Thread Starter
Thread cleaned up, drop the politics and bickering, you've been warned.
Posts have been deleted, posts that had snippy replies or quoted a deleted post have also been deleted.
There appears to be some good discussion in this thread so keep it on topic or move along please.
Posts have been deleted, posts that had snippy replies or quoted a deleted post have also been deleted.
There appears to be some good discussion in this thread so keep it on topic or move along please.
08-13-2022, 05:58 PM
#67
Thread cleaned up, drop the politics and bickering, you've been warned.
Posts have been deleted, posts that had snippy replies or quoted a deleted post have also been deleted.
There appears to be some good discussion in this thread so keep it on topic or move along please.
Posts have been deleted, posts that had snippy replies or quoted a deleted post have also been deleted.
There appears to be some good discussion in this thread so keep it on topic or move along please.
08-15-2022, 06:48 PM
#69
08-16-2022, 08:21 AM
#70
During this time, you will see constant, very gradual minute improvement of running characteristics. A new engine after two hours of factory prescribed break in at the beginning of the season, and the same engine at the end of the season, can easily show an improvement of 200~500 RPM on the same fuel, plug and prop.
That is why most gassers can take an entire season to settle.
This should not be confused with the normal use of the word "breaking in", which is used to indicate the time period needed to get the engine sufficiently broken in to be able to be used without limitations (aka "continuous full throttle"), which is dependent on several factors but usually takes 2 hours max.
