aspeed

Good to know about the Macs pipes too. I hope they keep making them as needed, not just liquidating them.

sarpet

but novarossi engines are heavy and very high reving engines,.26 engine needs minimum ground rpm 16000 that it work well in the air and ifound that 19200 ground rpm was very good for flying prop was apc 8x4 and plane little over 1m span awk thun combat plane.
​​​​​​​

1QwkSport2.5r

But!! Novarossi is still in business and Fox isn't... So they must be building engines people can and ARE using still to this day. If you want a custom made stump puller, Dubb Jett builds your engine to your needs/specs. Not cheap, but you don't have a lot of options these days unless you're willing to settle for OS' bovine scatology.

aspeed

A Novarossi is not that heavy. They look beefy, but the fins add to the strength. It is not so much the power to weight ratio of the motor, but of the airplane overall. I noticed the Novarossi site has dropped most of the airplane motors, at least Planethobby. I hope that is not the case, but just a site glitch. I do want to get a .28 at some point. We are $1.40 exchange rate right now, so I don't feel like going for it right away, especially when I have maybe 200 motors laying around the house. And it is true, the options are limited if you do not want OS.

1QwkSport2.5r

Look at Novarossidirect.com as well.

Sport_Pilot

I suspect that in the future all glow engines and maybe very small gas engines will be custom built. Just as older models are laser cut on custom orders. Engines may even have computer printed cases and other aluminum parts, with CNC machining. Similar to what Dubb is doing but with no cast parts. I don't see any other way if you want to have a large selection.

earlwb

As the performance of the engine goes up, they have to beef up the crankcase, make a larger crankshaft, use larger bearings, put in special reinforcing webbing. Flex and vibration are the curse for more performance. Thus the high performance engines become much larger in size as compared to their predecessors. Some of the model engines were video taped using high speed cameras. You could see the front end of the engine whipping around at high RPMs. Then a newer improved version that is all beefed up and it had much less flex or whipping around on the front end. it was one reason the front end of the engines being removable was discontinued. The entire front end would flex enough to scour down the gasket seal or O-ring there.

gmeyers

Nova Rossi engines are heavy because it takes more metal to solve the strength issue which occurs due to the metalurgy. Fox and K & B used higher strength alloys and kept the metal mass down. The K & B boat engines with the bolt on front crankcase hold up at that end but when run on 65% nitro at high rpm the con rod fails first and punches a hole in the case otherwise the casting is sound. I like the Italian engines like Rossi Nova Rossi and even Supertigre as they all have their assets.
The real driving force in the hobby is cost and more recently competition from electrics. Some of the fabulous car engines are Nova Rossi clones.
PS: my favorite engine is a K & B 7.5 boat motor converted to spin a prop at 21000 ground RPM and it is holding together after more than 20 years of sometimes hard flying.

1QwkSport2.5r

Novarossi also makes many long stroke engines. They also use longer rods in many models to improve reciprocating geometry. Heavy or not, they blow the doors off many other Asian imported model engines in performance, longevity, and ease of tuning. Novarossi sets world records with their engines in RC car racing.

hsukaria

I looked at the Novarossidirect site. I got bewildered by the number of variants for each engine size. Like there are 5 or 6 variants of the 60 size airplane engine. But they sure look good. I'm sure they would be better than the OS 61FX I have on my Dirty Birdy and probably lighter. Anybody interested in buying a used OS 61FX, barely used?

Sport_Pilot

Was that on their site. I could not find this. But lots of used engines, with more used Fox engines than normal. And some excess Mac's pipe stuff.

earlwb

Considering that they haven't done anything with the Webra buyout yet. They are still trying to figure out what to do with it all. I would not hold your breath about Fox as they will not do anything with it until they get Webra sorted out.

sarpet

Weston is still selling webras and weston own engines use webras block.
webra aero
​​​​​​​west aero

Mr Cox

Those websites haven't change for the last ten years, if I remember correctly. I.e. they look the same now as they did before Webra closed down. I wonder what would happen if one actually tried to order something from them...?

sarpet

Iam made couple order from weston and everything is work very well.
​​​​​​​ihave .25 weston,it is very very good engine.

gmeyers

so dammitman I have a Q-500 fox engine and have never ran it but I understand they sometimes will come on and off their tuned(?) muffler/pipe The solution was to lower the nitro content and back the needle valve off 1/4 turn or so. I have lots of foxes starting with the .07 all the way up to a .74ABC . My favorite is the .40 ABC which turned out to be a real powerhouse. I also like the .46ABC as well. The ringed engines and the lapped engines are pretty good too but won't stand up to the kind of abuse I give em.
Holy cow your post is an old one.

Charley

My Feedback: (2)

I raced with the Q-500 engine. If it won't come onto the pipe the quick solution is to pinch the fuel line momentarily in order to lean it out. When it's on the pipe it draws a lot more fuel than it does off the pipe, so it may be too rich to rev up into the pipe's RPM band. You can run into this with any narrow band pipe. Er, this presumes it has been tuned for max RPM when on the pipe previously and that it has the right prop on it that will get it into the RPM range the pipe is tuned for.

CR

fujiman

My Feedback: (133)

I have a Fox Hawk .60 factory tuned pipe 'm not using. Have it posted for sale here on RCU. Any takers? Check it out.

gmeyers

fujiman - sorry I'm not a collector though I do have a lot of Fox engines (almost all ABC) probably a dozen or so. I might be interested in an Fox Eagle 60 ABC

fujiman

My Feedback: (133)

super just let me know!!!!!!

Lou Crane

ON May 15?, EARLWB wrote:
As I recall, that may have been in a magazine article -? MAN ?- during the late '50s/early '60's! There were no video cameras back then - the photography was done with strobe lighting. The rate of flashes could be adjusted. At the correct rate, a rotating "device' could be illuminated at the same point in each revolution, in effect stopping it visually. A higher rate would illumine it as though it was rotating backwards (or vice versa.) The effect was like the apparent rearward rotation of auto wheel spokes when filmed by shutter operated actual-film movie cameras, or electronic frame rate video capture, at rates not matching the rotation.
Strobe-captured images could 'catch' the same position in a rotation, or some multiple that made it look 'stopped.' The flexing of the engine was highly visible! I don't remember it being 'captured' ONLY for bolt-on front end-engines - possibly an age-related "brain caused fragrance-augmentation?"
What most amazed me, even then, was that cast aluminum, even pressure die-cast aluminum, was rather brittle under distortion like that, yet these engines went through it and held together! (Pity they didn't bounce that well off concrete/tarmac/etc. ...)
Add edit: Of course, there were video cameras back then - we did have television! Suitable hookups to use strobe lighting may even have been around - usually, I'd expect, in some exotic laboratory experiments.

gmeyers

EARLWB I understand the whipping concept but I have seen lots of engines, ducted fan, marine etc. turning tremendous rpm's with extreme loads and it never seemed to matter the manufacturing technique, materials etc. whipping was never a symptom of a failure. I have a special K & B marine converted to spin a prop that has been a faithful, reliable engine since the mid 1980's without any issues (still use it today). I have seen boaters with failures and doing the post-mortem determine failure was due to a connecting rod, bearing etc but never whip related. I have seen similar videos taken of running engines and was amazed by the amount of crankcase or cylinder distortion during a high nitro test. On the other hand I see engine manufacturers taking special care to reinforce the shaft end of the case with webbing or heavier metal stocks especially O.S. Personally I think the old engine makers have done a marvelous job and over the years provided us with good reliable equipment for our hobby..

aspeed

Now the webbing seems to be the answer on the Novarosssi and more recently refined motors. Some of the older ones with the steel pistons would shake a lot and would fall apart I guess. I kind of like the bolt on case, as the rear bearing comes out easier, and they can run backwards too. K&B later machined the front piece all at once when CNCs started taking over, and they all ran more consistently. No more reamers coming from the other side to misalign, or whatever. I think the one piece is mostly cheaper and lighter, so it is just the way to go after the CNCs came in around the 1970s. Thought I should mention that the Nelson motors had a whole cylinder fracture and pop right off hitting the pitman in the knee. Lots of stress there when revving at 30,000 rpm or whatever. The FAI speed motors even have the engine mounts right up by the front bearing and rear bearing to stop the whipping. A solid mount on a pan is important for high rpms and in some cases they will have a shaft run with the counterweight of the single blade propeller shaking the whole plane and motor apart. at over 40,000 rpm!!!

earlwb

gmeyers, the whipping motion robs the engine of power. The up and down and or sideways motion of the crankshaft and front end of the engine takes some of the power away from the propeller. The power is not being transferred smoothly straight to the propeller. It isn't normally a cause for failure, but it could be a contributor though.

Aspeed, the single piece crankcase without the bolt on front end actually helped to stiffen up the crankcase more. Using webbing, etc helped too. It was possible with some engines having bolt on front ends to have the front end move around enough to scour away the gasket seal.

it would have been nice to find that high speed video clip of a model engine front end whipping up and down at high RPMs. But I can't find it anymore. Maybe the website went away taking it with it.

aspeed

I am sure the whipping would wear out the gasket after a while. Some motors you can actually see the front moving around at idle, or certain rpms. Some motors actually had a pretty snug fit and were likely better than others like the K&B maybe. The Little .02 and .010 TDs with the plastic tanks are bad for the shaking. Some will pick up rpm if you hold a screwdriver handle on the cylinder to keep it still.