allanflowers

Jeffski, you are right on the money with your suggestion.
No matter what happened, crash or seizure, the engine seems to be shot. Once I pull things apart I will know more.
In any case, I have decided to drop the RCV idea. It originally made such good sense - the torque made possible a near scale sized four blade prop, the side starting worked well with the D.III spinner design which makes normal starting difficult, the exhaust worked out beautifully and the dummy engine workout is ideal. I even liked the "geared" aspect which is like the Siemens Halsey in the real plane.

My Saitos (in four other planes including a Camel and a Pup) have NEVER let me down like this. A friend, who won Scale Masters a year back in Team Scale, also has had problems with an RCV - and I understand he abandoned it too.

I have spent the last two days on the internet checking sizes and prices - and on my CAD system looking at the installation options... I looked at OS but the Saito 72 looks good in this cowl and can hang to the side, slightly down in a place where it will get some airflow. The exhaust workout is still a question but I have some ideas. Same with the throttle servo and linkage. I will have to rework the dummy rotary engine and install a new engine mount (no fun at this stage) but it looks like the way to go. Carb height relative to the tank is not ideal but I may consider an IronBay fuel regulator to resolve that issue. The OS-FS-70-Ultimate-P(pump) has space problems because the fuel lines go staight back and there isn't room for them.

Abu, I was thinking of writing you to suggest you consider alternates for your CI but you also are way ahead of me.

On a more positive note, I flew in the One Eighth Airforce meet last weekend in Mesa AZ with my VK Camel (wanted to take the D.III but....) and won the Commander's Award. It is really cool, a big wood plaque with three airforce "wings", a nice embroidered patch AND TWO 50 Cal. SHELLS! I can just hear Tim the-tool-man Taylor making a grunting noise.

abufletcher

It's always depressing to have to do serious "reengineering" (and "re-engining") at this stage. But then that's often what the original designers had to do.

After it's initial teething problems, my RCV91cd seems to be running beautifully. Starts easily and can idle down to an incredible 1600rpms. But I never like putting an "unflown" engine in a serious scale model. It's nice to get to know an engine and how it performs before a maiden flight. It takes time for me to learn to trust my engines. Before I installed it in my Snipe, I put probably 10 hours of flying time on my Saito 72 (in a Cub ARF). And I'd like to do the same with the 91cd. In the end, I think the SP-series is a whole different beast from the CD-series.

allanflowers

You're probably right about the CD's although I wonder how it will compare with a Saito or OS. By the way, I had at about 2-1/2 hours on my RCV60SP before it actually flew, so it was fully broke in.

In rechecking the Saitos, it looks like the new 82 uses the same case as the 72 and would also fit in my cowl. It has 1.5hp compared to 1.2 and should be able to swing a four blade 14x4 Zinger.
That would be great.
I will be giving this some thought. The more powerful engine might also run cooler.

abufletcher

Time on a test stand isn't the same as time in the air. And it's also not just a matter of breaking the engine in. For me, it's about learning the "feel" for the engine when I'm flying. It's things like how it sounds on a fly-by and at a distance, does it have any "sag" at any point, does it hold a consistent idle during a taxi?

Here in Japan, the 82 has a bad rep. Since it is just a 72 bored out it supposedly is more prone to vibration because of the thinner cylinder wall. Anyway, that's what the "Saito guy" at our field says and he's a big supporter of Saito. He has the same misgivings about the FG-14 gas engine because that also used the same 72/82 casing. You may be overthinking the engine choice. At this point, I'd go for a completely standard choice. The 72 is already larger than is probably necessary for a model that size, but nevertheless a good choice. If it'll fly my Snipe, it'll definitely fly your DIII. The 82 just seems like overkill. And remember that a bigger prop with greater torque means more problems on take-off. Frankly, I'd happily "sacrifice" the four-bladed prop in favor of more traditional solution.

abufletcher

I think it's pretty obvious that the quality control at RCV isn't to the same standard as Saito or OS. But potentially, if you get a good one, I think the RCV-cd series can be a great engine maybe on the par with a Laser. The SP-series though, being a much more radical design, is more of a crap-shoot.

jeffski

My cd 130 will swing a 16x 6 master 150-200 rpmslower than my saito 120,but so far has only 3/4 hr run timeon it,so with a bit more timeit should be just as good as the saito
Abu,flying the 91 cd in a 'hack' model is a sound idea,back in the day did the same thing with new radio gear 'just in case' ! glad them days are gone, and you are almost right about the s.p. not so much a crap- shoot,just crap.Still, if I can sort out a water coolingset-up may use it in my C.1 yet !

abufletcher

What I'm saying is that, if possible, I like to do this with ANY engine, not to run in the engine but so that I can get to know the engine. I suppose if I couldn't do this, I'd just do a lot of "in model ground testing," For example, if you can't easily start and stop, start and stop, start and stop an engine three times in quick succession then there's something wrong.

allanflowers

I have been looking into several engines. The Saito 82 has mixed reviews. Some people love it but, as Abu said, many find it to have a LOT of vibration. It also is reported to run hot, not what I want. I could buy three of them and break them all in - then select the smooth one for installation - $$$$
They would still drain my 8.5oz tank too fast and I don't know for sure if they would really swing a four blade prop, which is the whole reason to go up to this size in the first place.
The OS engines in the 70 range, including their new 81 (obviously a response to the Saito), are too long and too tall to fit.

It looks like the Saito 72 is what I want. It still doesn't fit without some carving away, which I am not afraid off. I need to look at the California Dawn Patrol schedule and decide whether to order a new one or pull the one out of my Camel, at least for fitting purposes. Either way, there is no feasible way to make the Hemet Scale Masters Qualifier in early April. Plus, the tax man comith soon and my AZ house also needs some roof work...

Charles_e_bates

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ALLAN:

Well it's time for me to go to Japan.
At long last Sunday i fly out of LAX. at 11:00 A.M. and should be in Japan 4:30 P.M. Monday night.[X(]
I would like to take this time to thank you for your help on my Cyclone 30 drawings and i would hope one day i'll run across another kit of the Cyclone 30.
I would love to pick up another kit SO IF ANYONE HAS ONE PLEASE LET ME KNOW.
I'll keep up with your work and might put in a line now and then.

See you on the web.
Charles E. Bates

abufletcher

Yokoso! Welcome to Japan!

Charles_e_bates

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thanks.
I'll be in Atsugi along with my planes.
How far away from you is that?
Come and see us.
Charles E Bates

BobH

My Feedback: (2)

Allan did You look at the Laser 100? Laser engines are probably the BEST of the lot. I own a few so I'm speaking from first hand knowledge. Lasers have a lower profile too which might help in your situation. Eight and one half ounces isn't a lot of fuel but it should get you through the manuvers requried for Scale comp.

Just some thoughts...

allanflowers

Bob, I will check out the Lasers - have heard nothing but good things about them. This may take a while though and $$ is an issue.
Charles, I used to spend some time in Atsugi (Nissan Tech Center is there) and always enjoyed a place called MacArthurs Garage, a cool bar near downtown. http://www.macarthurgarage.com/
I don't know how it is these days since I haven't been there in over ten years. Have a great time. Japan is fantastic.

allanflowers

Here is a shot taken by Del Perena and shown in our club newsletter. It was taken right after I rescued my D.III from the weeds and mud. Believe it or not, a lot of weeds had already fallen off before this shot was taken. It had been worse.
I think it was a miracle that the plane was not totally destroyed.

I am still looking at engines to replace the RCV60SP... Do you blame me for wanting a different option??

vertical grimmace

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Schuckert meets Creepshow!

abufletcher

Early WWI attempts at camouflage! Seriously, I think the massive weed coverage is WHY the model survived. It's similar to when my Legionnaire and Puppeteer went into the bamboo. It looks dramatic but really it's the best possible cushion for a high speed impact.

Charles_e_bates

My Feedback: (90)

Allan:
NO we do not blame you for wanting on a different option, i would also.
Thanks fot the tip about the bar, i'll check it out and let you know if it still open.[:-]
Live from Japan.[8D]

Charles E Bates

allanflowers

The Saito 72 (ebay, almost new) was mounted to a 60FS Dave Brown mount. I had to relieve the base of the mount some to position the engine closer to the firewall – to insure the correct propeller location.
It was mounted to my break-in set up and started right up. After about 40 minutes, I am getting close to the final settings. The rpm range at this point is 1800 to about 6000, which I think is good enough to mount into the plane now. It runs very well, like every Saito I have had. My break in setup keeps coming loose as the c-clamps are not reliable. I can do the final adjustments in the plane.
The good news is that, if properly primed, it will start right up with a chicken stick – important because of the D.III’s fiberglass spinner complicates using a conventional starter.

abufletcher

[X(][X(][X(][X(][X(][X(] Your Saito 72 (like mine and every other Saito I've had, tuned by our local Saito expert) should be have a high end of at least 9800 and even up to 10200 would be ok. At the low end, I end up at about 2800. I certainly wouldn't risk flying a Saito engined model at 1800 to 6000.

allanflowers

As I ran it, the oil started making the C-clamps loosen up faster and faster. By the time I got to about 35 minutes, I couldn't really tune the needle valve, control the throttle and hold the tachometer and still be ready to act fast when it started to loosen up. So I couldn't really safely lean it out properly on this set up (I need ALL my fingers).
Once it is mounted safely, I can make my final needle valve adjustments and get it to 9500 or so. I am using a 14-6 Master Airscrew for break in but will then probably go to an APC 15-4, like on my Camel. I wish I could drive a big four blade prop, like the one I had on the RCV but that is not going to happen.

EDIT!!!
I just realized I had my tach set for a THREE BLADE PROP.
So.... it is not 1800 (that would be amazing) and 6000 but rather 2700-9000 at this point... and still running quite rich.

allanflowers

I tore down the plane so I can get at the insides. It is amazing the damage is so little considering the straight in crash. The RCV is stoved in and barely turns. I will open it up for a look. The 1/8” aluminum spinner plate was bent back and must have taken quite a blow. The wooden engine “spider” is one of the few things that will need real repair.
Fitting the Saito 72 required a bit of grinding on the fuselage side. Next I must accurately center the mount on the firewall so I can drill for the new t-nuts. The tank will have to be pulled at that time.

allanflowers

I located the centerline of the firewall for the new mount, drilled the new holes and installed the new t-nuts. The tank and one of the servos down below had to be pulled to get inside to install the t-nuts.
Next, after relieving the fuselage a little more for better airflow around the cylinder, I worked on the exhaust system. The pipe has a couple of bends and needed trimmed by about two inches. It will look pretty good with only a small bit showing underneath.