I have purchased a nib Rossi .65 rear exhaust ducted fan engine from a friend. It has no instruction manual with it, however. I am new to jets and plan on putting it in a Regal Eagle. I have gotten the feeling that Rossi's are a difficult motor to master. I've noticed posts that Rossi .91 motors work better with an OS carb. I have also read that in jets a remote mixture control is needed, something else I am unfamiliar with. Does this apply to the .65 as well? Does anyone know what size carb I should use if a carb replacement is needed or can someone tell me the way to tame the Rossi carb?

Well, tomarrow I am going to the Toledo show and would like to inquire as to what I will need to make this thing work without frustrating the heck out of myself. What type of fan should I use? What about pipe and fuel source? Cost is an issue, but not an overwhelming one, I want something that works and is reliable. I'm not concerned about all out speed or anything with this my first jet, just something that works and I can grow from with.

I know its a big list at such late notice, but I only found the motor wanting a home this week and have been out of town so it isn't something I have been able to plan out or research as well as I would like.

thanks in advance for your help

bob

That engine is just awesome once you master it.....3.5 hp rating with NO NITRO!!!!!
Must have tuned pipe.....got one?
Fuel mix..........have used these in helicopters many hours............ 12% Klotz, 1% castor, in one gallon of methanol. High needle set at 2-3 turns out and the idle set the same. (on that engine set the idle on the bench and then set the high side.
If you have problems send me a PM and we will exhange phone numbers. It is an awesome powerplant when you get it right. Best damn glow engine out there, but needs the right fuel mix.
Jack

Hi Helijack

1% Castor - is that a typo? I would think it needs to be 10%. Total oil 22%.

Bob, don't mess with the carbs(OS). The Rossi runs very well as is and with the right pipe and fuel as Helijack says. This motor will idle for ages without quiting(any DF jock will know what I mean-motor quits just as you get to the end of the runway and ready for takeoff!). Remember that these poor DF motors are streched to the max and just need some patience in setting them up.

One strong motor.

Zane

Well guys, don't let anyone ever kid you that the Toledo show has everything that is in rc flying. There was no Rossi representation whatsoever. There was one electric ducted fan model. NO other ducted fan models, units, or representation whatsoever. Don't worry, the turbine guys did not fair too well either. There were two in the static judging, both the same non-scale model and it was represented in a display booth as was one other. That was all there was in jets, period! I was really dissappointed. The swap shop was mostly junk and there were no bargans to be had. Everything in the place was going for list price.

Either jets are gone over the horizon or the cost of display is just way too high for smaller companies. There were a number of smaller companies displaying though. Any idea what gives?

bob

I think the jet manufacturers, as you may have guessed, have for the most part stopped doing shows like Toledo because it just does not pay, they can hit their audience much better at the jet rallies or through advertising.
The Rossi 65, had one, hated it, could never get any reliable flight out of it, would not touch one with a ten foot pole. Relaiable means being able to get up and down, say, ten times, without a deadstick...and that is MOST unlikely with any of the rossis I have owned, the 65, 81, 90. Probably why they are outnumbered 25 to 1 by OS engines. The rossi has an in flight mixture built into the carb, which is a nice feature.
Frankly...I would not go near one again. A few guys have mastered them, or at least they say they have, but I have never SEEN a DF rossi motor actually give a consistent performance at the field. On the other hand, I have seen(and had) many flights with the OS 91. Find one.

No, 1% was not a typo. Those engines run best on 11% oil, I didn't have the balls. I run them at 13% I also found out they run 40 degrees cooler with the 1% castor. The oil I found most successful was a total of 13%. Best temps, best starts, most consistent.

Now, I must also add that I only run my glow machines with a header tank and the "Uniflow" system. This gives a consistent pressure to the fuel system and the engine is constant.

Rossi themselves recommend 10% castor.

Reliability? Treated properly and as outlined above, I only had to auto in one time in 7 gallons of fuel, and that was my fault. Jack

Helis, though, not jets? Different environment.
Hey, your pays your money and you takes your chances, you can find used Rossis at boat ballast prices all day long, but OS is another story. Go to the field and see why. That's my two cents, it's worth just about that, two cents.

I've seen a couple of Rossi DF's on my field. Don't know if it because theya re old but their owners sure spend a lot of time setting them up, and they not always achieve the setting that they want.. I love my OS .91, just go the field, fuel and fly.

But thr Rossi sure beats OS when it comes to looks. That is one georgeous engine.

Bob,

I hope you fly off of pavement, beacuse a .65 powered Regal Eagle is not going to like grass fields. I know Parkinson says it will fly on a sport .61, but that is with fixed gear and a very light airframe.

Depends on the fan you going to to use, with the regal eagle you can take ofF from grass.
the pusher byro-jet give more power for take off , but IS SLOWER IN THE AIR. but if you use turbax 3 or dynamax it will be harder to take off from grass . use the byojet for .65 for grass-take off . anyway you have to build it light .

alfred

Out of the 4 Regal Eagles I have built, the one that flew off of grass the best, was one powered by an OS.91 and Dynamax fax. It would get off of grass in about 150' and climb out with authority (for a DF). It had Spring Air retracts, Robart struts and Compact Unibrake wheel brakes. It also had a self made bifurcated thrust tube. Pic of it in my gallery.

The lightest one I built was OS.77 / Byron fan powered. It took about 450 - 500 feet to get off of grass if there was a head wind. If the wind was cross or completely calm, it might not get off at all. It would get off of pavement in about 150'

Hi,
Hope I can help,
Your rossi is a great engine.
If we take a (any) fan and calculate the pitch / diameter / rpm.
and then check tailpipe velosity we will know how heavy and wing loading to build the jet.
So if we take the (for instance the Dynamax) if it flys a jet at 21000 rpm then any engine that will turn it at 21000 rpm will work.
I have spent a good part of my life testing (i love jets) An os .91 will do this without to much messing around.
However a Rossi .65 will also do this but it does take a bit of setting up to get it to Idle. I have found that once you get the Rossi to perform it just might out rev the OS.
The only downside is that it takes a .65 longer to reach RPM's than a .91.
However off grass this does not matter because the jet will sit there and not move untill the rpm hit about 18000 then off it goes.
On pavement it will take longer runway because it is rolling whil it is reving up.
If you have a normal mowed grass strip and a regal eagal does not take off in 50 - 70' then please call me. www.rcjets.com
Bob Parkinson