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FT What Did You Do RC Today : Caution Offtopic At All Times

Wildthing

Legendary member
So you two engine experts @speedbirdted & @JennyC6 , do you know of any carb that would interchange with the one on my Webra 20? It runs but it's not reliable that I want to try it in the air, it's old and the barrel and needle valve are just sloppy and of course it is obsolete.
 
I'm almost certain you blew up the engine by using that 11-7 2-blade prop. Just not enough load. The 11-7-3 is barely enough and they will tolerate up to a 14-4 if you want to be abusive, lug them a bit. 11-7-2 is just not enough, overrev, sheared a pin off. Could do it again with the OS Surpass crank in there as well.
Honestly my main concern with overspeeding was the valvetrain. I'm guessing if I pushed it too hard some valve float issues could crop up, and the power would drop off drasitcally. I don't think the crankpin would have popped if there was nothing wrong with it; after all, I don't think there are many differences between a 2 and 4 cycle crank other than some method of driving the cam and no intake timing hole (I would think it might even be a little stronger, as I have seen 2-cycles bust cranks right at this hole) and 2-strokes regularily turn much higher RPMs without the crankpin going on any adventures.

So you two engine experts @speedbirdted & @JennyC6 , do you know of any carb that would interchange with the one on my Webra 20? It runs but it's not reliable that I want to try it in the air, it's old and the barrel and needle valve are just sloppy and of course it is obsolete.
Most carbs with a roughly equal choke area will probably work about as well. If you can find one that fits the throat exactly, throw it in. Or you can have someone make you a nice little spacer to seal the gap.
 
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Stayed up till 2AM...literally...putting my Magnum 30 on Speedyboi in an attempt to see if 4-stroke power is viable. Attempted to fly today. Weather couldn't have been better! However I......pretty much wasted my time. A bunch of asshats with giant scale 3D birds were literally congalining the damn runway. 2-3 of them in the air at the same time doing their spaztastic nonsense and as soon as one landed to refuel another was already on the start pad getting the engine fired up. Was there for four hours only got 10 minutes of lazy high-altitude circuits around the flight pattern.

Not only was this annoying as hell, but it also made me nearly total Speedyboi. See, that little Magnum 30 is a hell of an engine, but something in the rushed last-second engine swap didn't gel right. I wasn't getting more than about 8500RPM on a 9-7-3 prop in flight, so I had to keep it PINNED just to keep it in the air. Plane flew great otherwise. I don't know if the problem is linkage, if the engine just doesn't have the balls, if it's disagreeing with that prop, or some combination of the three, but it just did not have any power. And because I'm having to do 150'+ height lazy flight pattern circuits to clear the 3-4 air hogs spazzing out over the runway I can't get a feel for how to land the thing with so little power. I had to just wing it in a 30 second window while one was starting their engine and the others were running their fuel pumps. I ended up stalling it at waist height, dropping the piano, bouncing it almost back to its same height, and dropping the piano again. It missed hitting the chainlink fence guarding the pilots by about half an inch, stalled the engine out in the process.


Speedyboi is a portly li'l thing, so he took the hits in stride. No damage. But still. I had no chance to feel out what throttle setting I should use for final and touchdown because these damned 3D pilots were doing their spazzy 'I don't know why I even have wings on the plane' nonsense.

Needless to say my already indifferent attitude towards 3D flight has taken a sharp decline. It's getting hard for me to not give anyone grief over what they fly when a certain type of flyer enacts a hostile takeover of the damn field and blocks out anyone else from flying. I wasn't the only one frustrated by it either; nobody was saying it but I could just see the looks on the faces of the other pilots that wanted to fly something not an Edge or Extra or Yak. Homey two tables down from me had an Avanti and A-10 EDF; he was there before I was and he only got one flight on the Avanti in the time I was there before he shook his head, packed up, left.

I probably could have waited the 3D spaz show out but I found myself getting so damn grumpy about the air hogging that I wouldn't be able to enjoy the time in flight when I finally got it, so I just said -beep- it and left myself. Maybe I'll try again tomorrow maybe not.
Honestly my main concern with overspeeding was the valvetrain. I'm guessing if I pushed it too hard some valve float issues could crop up, and the power would drop off drasitcally.
These are not interference engines. Valve float would make it miss at high speed but not much else. I'm also not convinced they even can rev high enough for valve float to be an issue just due to the cam grind itself. They're designed to make their power in the 7500-9500RPM range.

I don't think the crankpin would have popped if there was nothing wrong with it; after all, I don't think there are many differences between a 2 and 4 cycle crank other than some method of driving the cam and no intake timing hole (I would think it might even be a little stronger, as I have seen 2-cycles bust cranks right at this hole) and 2-strokes regularily turn much higher RPMs without the crankpin going on any adventures.
Two strokes have a constant compressive load on the crank pin at all times, as in the pin is always being pushed towards the centerline of the crank. There is never any tension on that pin and it never has to jerk the piston down at the top of the stroke. Even at teh bottom of the stroke things are cushioned by the air/fuel charge in the case.

Four strokes are the polar opposite. There's three 'dead' strokes for every one 'live' stroke. The crankpin is alternating between the piston tugging it away from the centerline and pushing it towards the centerline. 4-strokes also hit harder in general. The difference in stresses is why 4-stroke crankpins will shear off when 2-stroke pins do not; they also often tend to be more substantially built. A lot of my 2-strokes have hollow crankpins; none of my 4-strokes have one.

Prop for no more than 9750RPM on the ground and you'll be copasheeshy. 11-7-3 is about the lightest prop you should be using on a 52 4c.

If you had an OS FS-40 and wanted to rev the nuts off of it you could install the crank from the FS-40C. OS did a LOT to this crank to make it suitable for surface use(Some even had pips for a pull start!) and they will safely rev to 17K without issue. Similar things can be done with the FS20/26/30 'smallblock'; use the crank from the FS26C which is good to 20,000RPM. Can also fit the cam, head, carb from the car engines and really get a screaming 4-stroke setup for a smol plane.
 
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So you two engine experts @speedbirdted & @JennyC6 , do you know of any carb that would interchange with the one on my Webra 20? It runs but it's not reliable that I want to try it in the air, it's old and the barrel and needle valve are just sloppy and of course it is obsolete.
betchya a perry carb would do the trick. Might be able to find a parts engine or somethin' on eBay with a carb that's in better nick.
 
Stayed up till 2AM...literally...putting my Magnum 30 on Speedyboi in an attempt to see if 4-stroke power is viable. Attempted to fly today. Weather couldn't have been better! However I......pretty much wasted my time. A bunch of asshats with giant scale 3D birds were literally congalining the damn runway. 2-3 of them in the air at the same time doing their spaztastic nonsense and as soon as one landed to refuel another was already on the start pad getting the engine fired up. Was there for four hours only got 10 minutes of lazy high-altitude circuits around the flight pattern.

Not only was this annoying as hell, but it also made me nearly total Speedyboi. See, that little Magnum 30 is a hell of an engine, but something in the rushed last-second engine swap didn't gel right. I wasn't getting more than about 8500RPM on a 9-7-3 prop in flight, so I had to keep it PINNED just to keep it in the air. Plane flew great otherwise. I don't know if the problem is linkage, if the engine just doesn't have the balls, if it's disagreeing with that prop, or some combination of the three, but it just did not have any power. And because I'm having to do 150'+ height lazy flight pattern circuits to clear the 3-4 air hogs spazzing out over the runway I can't get a feel for how to land the thing with so little power. I had to just wing it in a 30 second window while one was starting their engine and the others were running their fuel pumps. I ended up stalling it at waist height, dropping the piano, bouncing it almost back to its same height, and dropping the piano again. It missed hitting the chainlink fence guarding the pilots by about half an inch, stalled the engine out in the process.


Speedyboi is a portly li'l thing, so he took the hits in stride. No damage. But still. I had no chance to feel out what throttle setting I should use for final and touchdown because these damned 3D pilots were doing their spazzy 'I don't know why I even have wings on the plane' nonsense.

Needless to say my already indifferent attitude towards 3D flight has taken a sharp decline. It's getting hard for me to not give anyone grief over what they fly when a certain type of flyer enacts a hostile takeover of the damn field and blocks out anyone else from flying. I wasn't the only one frustrated by it either; nobody was saying it but I could just see the looks on the faces of the other pilots that wanted to fly something not an Edge or Extra or Yak. Homey two tables down from me had an Avanti and A-10 EDF; he was there before I was and he only got one flight on the Avanti in the time I was there before he shook his head, packed up, left.

I probably could have waited the 3D spaz show out but I found myself getting so damn grumpy about the air hogging that I wouldn't be able to enjoy the time in flight when I finally got it, so I just said -beep- it and left myself. Maybe I'll try again tomorrow maybe not.
I know the situation at your field is irritating, especially when it almost lead to the loss of your aircraft. That said, the language needs to be toned down a smidge more for these forums.

I wasn't the only one frustrated by it either; nobody was saying it but I could just see the looks on the faces of the other pilots that wanted to fly something not an Edge or Extra or Yak.
Perhaps if that desire had been conveyed directly to the whirling dervishes they would have paused?

When I'm doing a maiden I like to pick some visual cue at altitude, and practice landings relative to that; something like a line of clouds or distant object. Obviously visual cues are limited by your location and whatever weather you have. Assuming you can find something to fly relative to, it can give you some idea of how things behave when slowed down and you have a bit of altitude for recovery if it goes wrong.
 
I know the situation at your field is irritating, especially when it almost lead to the loss of your aircraft. That said, the language needs to be toned down a smidge more for these forums.
I've toned back what I wanted to say enough to avoid copping a ban for it. No actual swear words used.

Trust me if I said my mind in 100% unedited form every sailor from here to Timbuktu would go 'whoa dude'.

Perhaps if that desire had been conveyed directly to the whirling dervishes they would have paused?
Maybe. Have my doubts. The might have just paused long enough to give you a window to get off the ground and then gone right back to running their little conga line.

When I'm doing a maiden I like to pick some visual cue at altitude, and practice landings relative to that; something like a line of clouds or distant object. Obviously visual cues are limited by your location and whatever weather you have. Assuming you can find something to fly relative to, it can give you some idea of how things behave when slowed down and you have a bit of altitude for recovery if it goes wrong.
[/quote] Wasn't a maiden for the plane. Engine, sure, plane not so much. If I'm perfectly honest I should have just packed up and gone home within the first half hour I was there but I thought they'd do the usual thing that goes on at the field, which is 'go up, have some fun, then land and let the other pilots have a chance to fly'. I normally don't have any bone to pick with the 3D guys because they don't normally hog the airspace so severely, but today you were not flying unless you wanted to risk a mid-air with a 25% scale Yak 55 or Laser or whathaveya.

Another thing they could have done would be to take advantage of how ENORMOUS the field truly is and do their 3D stuff off to one side. It's L-shaped and there's plenty of room for them to do this without hogging the airspace for everyone else.

the whole problem was the 3D pilot just being air hogs today. IT's abnormal and I hope it stays a rare thing.
 

Wildthing

Legendary member
betchya a perry carb would do the trick. Might be able to find a parts engine or somethin' on eBay with a carb that's in better nick.
So far no luck searching for a used engine, plus being such and old one I am sure it would be worn out also so that is why I would like to find a new interchangeable one. I will search for the Perry carbs and see what I can come up with.
 
So far no luck searching for a used engine, plus being such and old one I am sure it would be worn out also so that is why I would like to find a new interchangeable one. I will search for the Perry carbs and see what I can come up with.
Perry carbs are still manufactured. They are not cheap, but they work very nicely. You can buy them here; a #2200 carb should fit, based on the table at the bottom of the page for Webra motors.

Stayed up till 2AM...literally...putting my Magnum 30 on Speedyboi in an attempt to see if 4-stroke power is viable. Attempted to fly today. Weather couldn't have been better! However I......pretty much wasted my time. A bunch of asshats with giant scale 3D birds were literally congalining the damn runway. 2-3 of them in the air at the same time doing their spaztastic nonsense and as soon as one landed to refuel another was already on the start pad getting the engine fired up. Was there for four hours only got 10 minutes of lazy high-altitude circuits around the flight pattern.
The 3D heli guys at my field do crap like this from time to time but generally they don't crop up that often. Whenever I do 3D nonsense over the runway I make sure no one else is flying or trying to. If someone else decides to come out, I get out of their way at least long enough for them to get well out of mine. Something many 3D pilots seem not to know is that contrary to popular belief, 3D airplanes can also be flown in a pattern at altitude. :)

Not only was this annoying as hell, but it also made me nearly total Speedyboi. See, that little Magnum 30 is a hell of an engine, but something in the rushed last-second engine swap didn't gel right. I wasn't getting more than about 8500RPM on a 9-7-3 prop in flight, so I had to keep it PINNED just to keep it in the air. Plane flew great otherwise. I don't know if the problem is linkage, if the engine just doesn't have the balls, if it's disagreeing with that prop, or some combination of the three, but it just did not have any power. And because I'm having to do 150'+ height lazy flight pattern circuits to clear the 3-4 air hogs spazzing out over the runway I can't get a feel for how to land the thing with so little power. I had to just wing it in a 30 second window while one was starting their engine and the others were running their fuel pumps. I ended up stalling it at waist height, dropping the piano, bouncing it almost back to its same height, and dropping the piano again. It missed hitting the chainlink fence guarding the pilots by about half an inch, stalled the engine out in the process.


Speedyboi is a portly li'l thing, so he took the hits in stride. No damage. But still. I had no chance to feel out what throttle setting I should use for final and touchdown because these damned 3D pilots were doing their spazzy 'I don't know why I even have wings on the plane' nonsense.
The prop certainly has something to do with it. The manual recommends a 9x7 2-blade as the steepest in the 9-inch range so I can see why a 3-blade would load it down a bit. I doubt you'll get much better results with a different prop though; I doubt the engine really has the oomph to haul the plane with the authority you'd want it to. Though it begs the question, do you get better results with that engine and prop combo on the bench? If you do, something else in there is playing up.

I've been thinking about my own Magnum engine though. I looked at some footage I took of it flying the other day and the prop whirring sound doesn't sound exactly... like a propeller. I really hope it isn't a bearing going bad. Perhaps a 3-blade just has a different sound that I'm not familiar with.

 

Wildthing

Legendary member
Perry carbs are still manufactured. They are not cheap, but they work very nicely. You can buy them here; a #2200 carb should fit, based on the table at the bottom of the page for Webra motors.



The 3D heli guys at my field do crap like this from time to time but generally they don't crop up that often. Whenever I do 3D nonsense over the runway I make sure no one else is flying or trying to. If someone else decides to come out, I get out of their way at least long enough for them to get well out of mine. Something many 3D pilots seem not to know is that contrary to popular belief, 3D airplanes can also be flown in a pattern at altitude. :)



The prop certainly has something to do with it. The manual recommends a 9x7 2-blade as the steepest in the 9-inch range so I can see why a 3-blade would load it down a bit. I doubt you'll get much better results with a different prop though; I doubt the engine really has the oomph to haul the plane with the authority you'd want it to. Though it begs the question, do you get better results with that engine and prop combo on the bench? If you do, something else in there is playing up.

I've been thinking about my own Magnum engine though. I looked at some footage I took of it flying the other day and the prop whirring sound doesn't sound exactly... like a propeller. I really hope it isn't a bearing going bad. Perhaps a 3-blade just has a different sound that I'm not familiar with.

I went to their website, found the interchange and came up with their 2020 not 2200 but whatever all good that way. But boy what a useless site, they have no way to allow people to order anything let alone see if they have it in stock. Sent them an email so will see what they say.
 
The 3D heli guys at my field do crap like this from time to time but generally they don't crop up that often. Whenever I do 3D nonsense over the runway I make sure no one else is flying or trying to. If someone else decides to come out, I get out of their way at least long enough for them to get well out of mine. Something many 3D pilots seem not to know is that contrary to popular belief, 3D airplanes can also be flown in a pattern at altitude. :)
That's exactly what I do. I also tend to get 4-5 flights in over a 5 hour period so there's lots of dead air time for others to fly during so I typically get a flight to myself
 

Wildthing

Legendary member
Well something RC today, pick up this little guy for only $50.00 CA , it is an OS FS-120 Surpass. Do I have anything to put it into , that's a big nope :D . It is cleaned up and lubricated, has really good compression, next to build a stand so I can fire it up. He was running a glow booster on it also for idling and gave me that setup with it also.

Now to search for something it will work on :)

IMG_4294.JPG
IMG_4295.JPG
 
Making the 1/10 Slash 2WD more driveable in the yard when the grass isn't extra short. Should work at the field and a few other places too. Picked up some wider/taller tires, adjusted the ride height up a scosch, and am going to paint up a Jconcepts BAJR body rather than butchering the stock body. Testing in the long grass of the yard has been very positive! Just need to do the body and it will be golden.

IMG_20210420_132520016.jpg


(yes, htat's a boring NiMH in it, but I do have a LiPo too!)

Cheers!
LB
 
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The Hangar

Fly harder!
Mentor
Making the 1/10 Slash 2WD more driveable in the yard when the grass isn't extra short. Should work at the field and a few other places too. Picked up some wider/taller tires, adjusted the ride height up a scosch, and am going to paint up a Jconcepts BAJR body rather than butchering the stock body. Testing in the long grass of the yard has been very positive! Just need to do the body and it will be golden.

View attachment 198664

(yes, htat's a boring NiMH in it, but I do have a LiPo too!)

Cheers!
LB
I got some of those tires for mine too - they sure made a difference!
 
Making the 1/10 Slash 2WD more driveable in the yard when the grass isn't extra short. Should work at the field and a few other places too. Picked up some wider/taller tires, adjusted the ride height up a scosch, and am going to paint up a Jconcepts BAJR body rather than butchering the stock body. Testing in the long grass of the yard has been very positive! Just need to do the body and it will be golden.

View attachment 198664

(yes, htat's a boring NiMH in it, but I do have a LiPo too!)

Cheers!
LB
I still run NiMH in my 2wd slash. I only use lipos in my planes and 4x4 vxl
 
Still running the stock brushed setup here and not breaking stuff. Probably go brushless at some point now that I'll be able to run it more. Supposed to snow here tonight and may stick to the grass.... will have to get the snow skimmer and this out tomorrow if it happens....