Welcome to Club SAITO !
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Yep, I remember now. Thanks
This is the thread I was referring to. Canardlovers thread on lightening Saito parts. RVM, Dowunder, and as recall Pete was there too being well, a rude ol fart.
http://www.rcuniverse.com/forum/glow...-saito-4s.html
I will be experimenting with raising the CR on one of my 82's in the near future to optomize it for 15% nitro. I'm just not sure yet what CR I should target. Any ideas on that?
This is the thread I was referring to. Canardlovers thread on lightening Saito parts. RVM, Dowunder, and as recall Pete was there too being well, a rude ol fart.
http://www.rcuniverse.com/forum/glow...-saito-4s.html
I will be experimenting with raising the CR on one of my 82's in the near future to optomize it for 15% nitro. I'm just not sure yet what CR I should target. Any ideas on that?
humm you could do all that on the lathe, in fact it would be better to do it on a lathe than to use an end mill, you could mount a jig to an independent jaw plate thew the back of the plate
I remember when I ran RC boats I increased the compression on a Zenoah 23, I did it on the lathe, but it was so long ago I can not remember how I went about holding the cylinder, I must have used the independent jaw plate..
you know the engine to do would be the FA91
Jim
Senior Member
i have two running and a third waiting for a plane and CH ignition
If you like flying at head height or lower quite a lot there is the occasional penalty to pay.The fa220 flew through the top of a wait a while bush and left it's aeroplane behind,so it's on the bench in the sin bin.I hope you finished the 7x57mm off they make a beautiful rifle.Be a damn shame if you had to give up that smelly muzzle loading gig,used a 45/70 black powder rig once on a calm day,fired and was surrounded by a thick cloud of blue smoke couldn't see fa.They must have been brave shooting dangerous game at close quarters back in the day before smokeless powder was common.
Planned to photo the conversion progress and show it on a photo page. I have a 150 Glow on my Rascal 110 right now. Had planned on going to a 120 but this engine may be just right.
If you like flying at head height or lower quite a lot there is the occasional penalty to pay.The fa220 flew through the top of a wait a while bush and left it's aeroplane behind,so it's on the bench in the sin bin.I hope you finished the 7x57mm off they make a beautiful rifle.Be a damn shame if you had to give up that smelly muzzle loading gig,used a 45/70 black powder rig once on a calm day,fired and was surrounded by a thick cloud of blue smoke couldn't see fa.They must have been brave shooting dangerous game at close quarters back in the day before smokeless powder was common.
FA82 Extreme Vibration.
Both my 82's vibrate something fierce! Two of my Sbach cowl screws were loose and one was missing after just a couple of flights. This after using thin CA to harden the holes in the ply several times. Last night I drilled the holes to 1/8" and epoxied in the yellow inner nyrod pieces and cut washers from tygon fuel tubing to serve as damping washers for the screws. I've had good results before doing that but man, the vibes are out of control. The prop and spinner are in perfect balance and all fasteners have been double checked. Tuning is not overly rich and bearings are new.
Has anyone had good results by "clocking" a slightly out of balance prop to reduce engine vibes?
Has anyone had good results by "clocking" a slightly out of balance prop to reduce engine vibes?
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I did that with a BTE Flyin King, I had removed a Fox 74 Diesel conversion bur didn't change the clunk line. The glow fuel hardened it up and it was sticking straight out in the center of the tank like a donkey dick. When the tank was half empty the Saito 80 went lean and kicked the Harry Higley Heavy Hub and the prop off. It then went tail heavy and sailed through the dead snag of a pine tree backwards with no sign of wings or tail feathers on it when it came out the other side. The engine and radio equipment survived. At 15.5 to 1 I don't think I'll increase that old 80's compression.
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Both my 82's vibrate something fierce! Two of my Sbach cowl screws were loose and one was missing after just a couple of flights. This after using thin CA to harden the holes in the ply several times. Last night I drilled the holes to 1/8" and epoxied in the yellow inner nyrod pieces and cut washers from tygon fuel tubing to serve as damping washers for the screws. I've had good results before doing that but man, the vibes are out of control. The prop and spinner are in perfect balance and all fasteners have been double checked. Tuning is not overly rich and bearings are new.
Has anyone had good results by "clocking" a slightly out of balance prop to reduce engine vibes?
Has anyone had good results by "clocking" a slightly out of balance prop to reduce engine vibes?
It's not vibes but torsional impulses, the result of a light engine and strong power pulses, exacerbated by a rich LS needle. A weighty prop helps.
Last edited by Hobbsy; 03-26-2019 at 05:15 AM. Reason: Add content
Both my 82's vibrate something fierce! Two of my Sbach cowl screws were loose and one was missing after just a couple of flights. This after using thin CA to harden the holes in the ply several times. Last night I drilled the holes to 1/8" and epoxied in the yellow inner nyrod pieces and cut washers from tygon fuel tubing to serve as damping washers for the screws. I've had good results before doing that but man, the vibes are out of control. The prop and spinner are in perfect balance and all fasteners have been double checked. Tuning is not overly rich and bearings are new.
Has anyone had good results by "clocking" a slightly out of balance prop to reduce engine vibes?
Has anyone had good results by "clocking" a slightly out of balance prop to reduce engine vibes?
I'll see if I can find a pic...
Think I still have that bugger if you care to try it
Last edited by Jesse Open; 03-26-2019 at 04:57 AM.
I repeat,
Imbalance and torsional impulses, both are forces that contribute to "vibration". Certainly BOTH are at play, not torsional impulses alone. Flywheels help to even or balance out torsional impulses.
(Under 10,000 words, as always)
Improved-torsional-measurements.pdf
Imbalance and torsional impulses, both are forces that contribute to "vibration". Certainly BOTH are at play, not torsional impulses alone. Flywheels help to even or balance out torsional impulses.
(Under 10,000 words, as always)
Improved-torsional-measurements.pdf
Last edited by Jesse Open; 03-26-2019 at 05:20 AM. Reason: Add a link to one of many informative reports. No corrections required
Sorry, your personal definition doesn't change the real definition.
https://fluidampr.com/what-is-torsional-vibration/
https://fluidampr.com/what-is-torsional-vibration/
Last edited by Jesse Open; 03-26-2019 at 05:27 AM.
Sorry again but NOT. You said it is NOT vibration, it is.
I said it is vibration. Part from natural imbalance, part from torsional impulses.
It IS vibration, your first statement was in need of clarification, like it or not.
https://en.wikipedia.org/wiki/Torsional_vibration
http://www.arpnjournals.com/jeas/research_papers/rp_2015/jeas_0915_2472.pdf
Okay:
Oscillation
Sorry Cap, it is a vibration. Plenty of support provided from engineering sources.
Had he left out the "not vibes", it would have been 'correct". It is indeed vibration, as I originally said, regardless the source.
Glowgeek was quite accurate referring to "vibration", as I also replied, the vibration is made up from several, not a single force.
"Torsional vibrations"
86-torsional_vibration_guidelines_-_tdf&clh.pdf
https://community.plm.automation.sie...it/ta-p/354698
Last edited by Jesse Open; 03-26-2019 at 06:53 AM.
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Thanks Dave, less weight is a winner. Now "Show me the money"! Lol
I don't expect the little fa50 to see a 300 rpm gain using the TH muffler, probably not even 200 rpm, but I am curious to see what the gain is. Probably too cold to be out testing engines where you're at but I'm a patient man.
I don't expect the little fa50 to see a 300 rpm gain using the TH muffler, probably not even 200 rpm, but I am curious to see what the gain is. Probably too cold to be out testing engines where you're at but I'm a patient man.
No hurry on your test runs Dave. Thanks.
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hey, I wont go into details, but I sure got suckered good again over on a other RC forum, I did a trade over there, the classified add said "brand new", haa I took it to be true, sent stuff I should get $100 for, in fact I was a nice guy, thinking it it was brand new and never used, I asked if he could use a couple things and when he said yes I sent 2 things I could have sold for $20, hey,> I'm a nice guy LOL,, well the thing came and I could see surely it was used a lot, I tested it and it does not work correctly so it is 100% useless.. so I PM'ed the site yesterday, I told them about the classified add and how it said it was brand new, and asked them how I should go about this with the Seller before I make a official complaint with the site, but no reply back to me yet form the site,
edit, think about it tho, if I end up sending it back I will be out a total of $30 for shipping both boxes, so ether way I'm suckered !!
the other thing I got suckered on (over there) was a muffler, LOL here too the muffler looked clean, actually it looked great, so when I sent the money order I put in a extra $4 to help pay the shipping, LOL when I got the muffler it was totally F n useless, the flange was cut so short the muffler would hit on the engine mount, it was one of those wide Bisson Pitts muffler, it would have taken $35-$45 in welding to fix it.. when I pm the guy he blamed me for not knowing how to fix it LOL, and at one point he said "all the older guys" he fly's with says there is nothing wrong with that muffler, at that I knew I was dealing with a punk kid, he did say he would send me back $10 but it never came..
any way, never again, never again will I deal over there unless the seller has 40 or more good trades
rant over LOL
2nd edit, Saitos are good, Saitos are great, I had one on the table when I ate
Jim
edit, think about it tho, if I end up sending it back I will be out a total of $30 for shipping both boxes, so ether way I'm suckered !!
the other thing I got suckered on (over there) was a muffler, LOL here too the muffler looked clean, actually it looked great, so when I sent the money order I put in a extra $4 to help pay the shipping, LOL when I got the muffler it was totally F n useless, the flange was cut so short the muffler would hit on the engine mount, it was one of those wide Bisson Pitts muffler, it would have taken $35-$45 in welding to fix it.. when I pm the guy he blamed me for not knowing how to fix it LOL, and at one point he said "all the older guys" he fly's with says there is nothing wrong with that muffler, at that I knew I was dealing with a punk kid, he did say he would send me back $10 but it never came..
any way, never again, never again will I deal over there unless the seller has 40 or more good trades
rant over LOL
2nd edit, Saitos are good, Saitos are great, I had one on the table when I ate
Jim
Last edited by the Wasp; 03-26-2019 at 10:53 AM.