MTK

Bob,

I think pretty much any airframe, not just wood. It seems to me that practically every offering at present should finish at 5 kg or less. The engine will handle that super.

Maybe on the flying....But Ed may get his Prestige in the air sooner. We built a soft mount for his model last week and I lent him the engine

I must admit to having so much fun during the flight we took, I ran the gas tank dry.... the engine quit, duh!. I misjudged and landed hard and tore the gear out of it. See, it happens to the seasoned vets too....very embarrassing, but I'm over it

aerobear

My Feedback: (4)

Can you tell us what size tank? How much flight time? Any rough estimate on how much fuel would be required to fly something like a masters sequence?
thanks

apereira

Does the engine has more torque than the OS160 for example?

MTK

Yes...OS160 on 20% nitro fuel is close but the edge goes to the Syssa on 87 octane gasoline at 100:1 oil. It's more displacement and if the engine is designed right, there is no substitute for cubic inches

MattK

MTK

320 cc tank from a 50 sized model. Enough fuel for about 1 1/2 Masters probably depending on how you fly it. I did not fly the masters sequence on the maiden flight. I would say there is enough fuel for around 10 minutes of normal flying (or maybe a bit longer, not certain).

The engine has a fairly large venturi and tends to use more gasoline than you might expect. This is totally consistent with the engine's power output. You don't get anything for nothing

MattK

kochj

This is SOOO true... 4-strokes have soo much bottom end, and very smooth power that is RIght away... Unless you compare a 50cc and up...2-stroke...gasser
But I am a rookie when it comes to pattern specific 2-stroke engines like the os 1.40 and a Miner 1.70. so I can't comment on these
2-....

I have not had ample time running a Evolution/mvvs on there pipe (seemed quite smooth) but I only had 2-very windy flights on a over-weighted airframe...
so I can't compare a 1.60 size gas 2-stroke.... however,
I can say that I am having one hell of a time dialing in my OS 1.20 AX on a macs header, and macs muffled tuned pipe....
I should have gone with there double quite muffler, as it would have not been soo senitive...
Followed specific instructions but I am getting too much of a "on" "off" swtich.... with a 17x6 APC and it is quite frustrating...
Or perhaps, I expect it to behave like a 4-stroke![:-]

Too cold to fly now!... well almost![]

kochj

It is a full composite (not a bad thing)
If you don't mind painting, the All white integral is a steal@ 1,200$

PlaneKrazee

My Feedback: (14)

The 120Ax will turn a APC 17X6W @ 9000 on stock muffler. What are you getting with the pipe?

kochj

APC 17X6 9,900-10,000 RPM's
Goes rich inflight untill verticle.
On ground it runs perfect set 200rpms off peak and
nose high it doesn't lean out, just increases slightly.

I should place the Poser box back on it, just to see if everything
else is fine....

I think I cut too many rings off the header....I set it for MAX rpm's...
A no no for 3-d and pattern, unless Racing....

cmoulder

A good friend has very generously offered me the use of an almost-RTF Aries (with FG fuse EDIT: Hmmm... composite? hard to find photos) for the Syssa project. It flew originally on an OS 1.40 and pipe.

My understanding of MattK's soft mount construction is about 99% complete now (after re-reading the thread several times, due to my density, not his photos and descriptions!), and I am confident that I can make one. And hopefully the firewall spacing won't require a lot of modification.

It would be nice if there were some way to access the carb needles through the mount, so that the stand-offs could be kept as short as possible, maybe eliminating any need for nose support. But it is what it is, so I will know more later after looking at the actual nose of the Aries fuse.

MTK

Bob,

Don't overshorten the stand offs. The practical minimum length should be no less than 1. 625". The reason is that the choke baffle needs to clear the mount or firewall (for those applications that have no soft mount). I initially cut mine to 1.500" and the choke actuation was sticky. The extra 1/8" was necessary. The total length from the baclk of the stand of to the prop drive washer will be 5.625"....that's the practical minimum.

If the mount is set further back, great. Todd makes several different stand offs and you can always cut and fit it exact. If the soft mount front gives less length than that, then you have little choice but to redo the firewall or extend the engine forward a little. Take extra care and think it through before you commit.

One more thing...make sure there is enough clearance around the chin cowl. The crankshaft length is shorter than typical which brings the cylinder far forward.

Let me know if you need anything else on that.

BTW, I just finished a new soft mount for the Syssa 30 for substitution for the ZDZ40 set-up in my new plane. Luckily there was enough chin cowl clearance. In this set-up, the firewall was set so far back (to accommodate the zdz40) that I needed a 1/4" spacer behind the soft mount, plus the longest stand offs Todd makes. That's how much difference there is between the two engines.

Matt

cmoulder

Matt,

Looking at those numbers it appears the Syssa with soft mount is not going to fit in the nose of the Aries. The distance is 6-3/16" from the firewall to the prop hub exit in the cowl, and it appears that even the OS 1.40RX was a pretty tight fit.

Also the pipe tunnel is enclosed - the pipe slides in from the front of the fuse, behind the chin cowl - and it too would be a very tight fit, if it fit at all.

Well, my friend also has a Petrel that was designed for petrol, so maybe we will give that one a look.

Into which model are you now installing the Syssa (after removing the ZDZ)? I am starting to wonder if any ARF designed for glow is going to work without doing major surgery to move the firewall back.

MTK

An original design...I had already installed the firewall, setting it up for the ZDZ, a rather long engine. The firewall had to be set to around 8" aft of the nose.

Is it true that many arfies don't have firewalls installed, leaving it up to the builder? if that's true, then it should be easy. No matter, If the soft mount is 1" thick, the minimum distance you need the firewall at is around 6.625" aft of the nose. If you built a thinner soft mount, judge accordingly. You may go down as thin as 0.7" and still have good isolation. But even with a thinner soft mount, the firewall distance may be reduced to around 6.3" or so.

I don't know what plane the Aries is. Is it the Japanese wood model? The way the Japanese models are designed, firewalls have to be built with notches and such, interlocking, so it would be a difficult retrofit. If it's something else with a glass fuse, the firewall shouldn't be that difficult to remove. Chances are the firewall is installed with glass strips so if you grind these away, the firewall should fall out.

Another option needs to be mentioned at this time....the engine is extremely smooth, more than any 2 stroke glow engine I have ever played with. You might simply consider to hard mount it and do away with the soft mount entirely. Just an idea.
Matt

NJRCFLYER2

My Feedback: (42)

I think it will fit in most ARFs. I've flown my Prestige for 4 seasons with the 140RX, and switching over to the SAP 180 now causes an added 1/16" gap behind the spinner backplate. Not bad. The chin cowl is definitely deep enough to contain everything too.

cmoulder

Thanks again, Gents, for your insights and suggestions.

I don't have the engine yet, so I will wait until it arrives to make a determination as to whether it is going to work with this model.

The [link=http://www.aeroslave.com/aries_pricing.htm]Aries[/link] is an early model from Aeroslave, and a predecessor to the Symphony. The model I am working with is the actual one in the photo. It has definitely got some miles on it, but is still serviceable.

cmoulder

It appears a good option would be a Focus II, because it has an [link=http://www.rcuniverse.com/forum/fb.asp?m=1954172]engine box on the firewall[/link], which is standard on about 99% of larger gassers and many glow planes.

It would be very easy to shorten the engine box, if necessary, for the home-made soft mount.

MTK

The engine was obviously very happy turning the 9400 on the pipe. Keep in mind that his exhaust timing is very long therefore the engine will tend to take advantage of light loads and spool up. Timing of our more typical glow 2 strokes in much more conservative, designed to allow more load at lower rpm.

An 18x6 is of little use to us in Pattern as Ed and Dave have mentioned several times.

To me, the proof came when we ran the 18.1x10 on my test bed. This model was around 11# 11 ozs as flown and is larger than most pattern models we fly today carrying over 1150 square inches of wing. Ed did a vertical rolling check to over 1000 feet and it still had plenty of beans.... we can't fly over this height at our field so it was cut short. This is a new engine afterall so that's why we have been excited about the prospect. After full break in, we expect better output

Matt
[/quote]

I finished a pair of composite wood props this week and got to run both of them today.

The composite woodies are XOAR electric wood props (very thin blades) laminated with layers of carbon cloth on both sides. How I do that exactly is a different story and I may write an article someday. Anyway. first up was the 19x8 woodie/carbon. This prop allowed the engine to really spool up. It sounded a lot like the Vess 18x6 Ed and I tried at Todd Syssa's place a couple months ago. Today was fairly cold and dry here in Whippany...around 38F. Under the conditions I ran the prop, the engine seemed to be a bit peaky and tended to jump on the pipe at around half throttle. I think I also had the low end a bit fat which contibuted to the jumpiness. Clearly however, the 19x8 is just not enough load spooling up to probably over 9k. You could hear tip noise. Probably would make a very good 3D prop.

Next up was the XOAR 19x10 woodie/carbon laminate which is a significant increase in load. I leaned the low end slightly and it seemed to jump less than 19x8. But even this prop appeared to be less load than the engine can tolerate...I'd put the rpms at around 83-8400, putting out excellent power.

I will play with 19x11 and 19x12 next, and see how these tame the engine. BTW these numbers are in ground running. Too cold to fly.

BTW, the 19x8 and 10 are both extremely lightweight compared to just about anything else intended for wet power systems... 19x8 weighed in at 60 grams and the 10 only 3 grams more. I also have a 19x13 XOAR woodie laminated the same way, which weighs 74 grams. The blade shape is different on the 19x13 and it may prove to be too much load. I haven't tried it yet but I will

MattK

Gungadin

Bob-Do you think the Syssa with the ES Composites pipe would fit the Focus II ?-Dan

cmoulder

I don't know, but I have been reading a build thread from a couple of years ago and looking at photos and it appears to be do-able. It has an open pipe tunnel, which seems to offer more flexibility than closed designs. So far all I have in my possession are the engine header and the ES pipe, with the engine arriving next week.

Despite the hurdles I encountered with the Focus Sport, I'd still take a chance with this one simply because I really like the way the Focus Sport flies. I am just looking for a full 2-meter model to do a few contests with next season (intermediate level) and want a gasser and obviously don't want to spend a lot right now.

At this point, it seems to be an attractive package. And nobody is jumping up and down with his hair on fire saying not to do it, so I'm inclined to go this way!

cmoulder

Looking forward with great interest to your test results, and your how-to for the prop modification.

Good thing I didn't start buying props yet!!

MTK

Bob,

As I recall, the Focus has an exposed tunnel very similar to the Temptation. I think they are dimensionally the same. The tunnel should accommodate the pipe. And BTW, if you need help putting together a soft mount, let me know and I'll try to guide you through it

Matt

cmoulder

Thanks, Matt, and I'm sure I will have a few questions about the soft mount. I already have a couple but will wait until I actually start working on it in case there are some more, just for continuity's sake.

Also it will be helpful to see what you and Ed come up with as far as the best header/pipe length, but from the rpm numbers you've already gotten it looks pretty good without much tweaking.

Gungadin

Bob-I am looking to do the same thing as you and I'm thinking the same way about the Syssa and the Focus II combo for next season pattern flying. What header goes with this set up and who sells it ?

Dan

NJRCFLYER2

My Feedback: (42)

You can use a header that would fit the OS 140RX. You might have some issues with the Hatori header, since if memory serves correctly, it's got a restricted opening. For our tests, we used a MAC header. I think we had to open up the bolt hole diameter by about a millimeter, but it's still usable on an RX after having done that.

cmoulder

Here ya go! You might have it all together before I do.

[link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXZ646&P=7]Macs header for OS 1.40RX[/link]

[link=http://www.escomposites.com/petrol.htm]ES 40G pipe[/link]