jnred123

Matt
Do you have a dimension front the firewall to the prop driver using your soft mount.
Cheers
Greg Hede

MTK

Greg, the plane was originally set-up for a much longer engine, ZDZ40F3A. The OS is around 3/4" shorter and normally takes a 1" thick soft mount. I built this particular soft mount extra thick (1 3/4") to accommodate the extra length, so to quote you a specific length of the cuirrent set-up will not do you any good. Sorry

jnred123

Thanks Matt, I want to convert an old Oxai Astral XX thats retiring from active F3A duty to the 33.
It has engine bearers to take the YS super mount so I'm undecided on whether to cut them out reinforce the firewall and mount off that OR leave the bearers in place and make an alum angle piece that picks up on the 33 standoff points and attaches to the bearers via a rubber interconnecting piece, what do you think?
Cheers
Greg

MTK

Greg, i don't know what the bearers look like. Would you take a photo for me? Are the bearers themselves soft mounted? Are they screwed in or do they need to be ground off?

If the bearers have a mounting surface that is on a common plane (top and bottom mounting holes on a common plane), the second option might work. Not sure about the "interconnecting rubber piece" tho.

You might be better off in the long run tocut firewall and bearers out and start anew. It would be lighter and probably stronger set-up.I use cross grained balsa/carbon laminate for firewalls. A soft mount designed for stand offs simplifies the installation. Stand off length I use is 1".

Does the Astral have a pipe tunnel long enough for the ES Composites 30G pipe? Which YS did you power it with? If it was the 160DZ or smaller, the Astral will come alive on the 33

JRgraham

My Feedback: (1)

Iam actually thinking seriously about replacing my YS170 with the GT33 in my Scandalous biplane for starters. My only concern is the nose ring part of the soft mount?
Imight throw a picture up later of the engine bay as it is now.

papaone

Hello

Find attached pictures of installation engine PTE36R and RCGF32 with 4 silent-blocs without nose ring.
It goes well.
http://shop.hpceurope.com/fr/categor...%C3%A9caniques

MTK

BTW guys, I sell some of the best gasoline fuel line available. It doesn't stiffen over time and sun exposure. I am still using the first tank I outfitted with the stuff, 4 years and still flexible, inside the tank and out.

I also make and sell custom pipe couplers. These are made from ceramic fabric andI have yet to burn one through, 100's of flights later.

Contact me directly at my email address if interested

jnred123

Matt
So your mount can take interchangeable stand off lengths?
It had a 160 originally but has a 170 in it now dialed right down to about 60% of full throttle on a slider.
Cheers
Greg

Zi-Chun Lin

We are working on brand new 40cc GS engine for pattern plane hope testing prototype before end of this year.
We are GP engine from Taiwan (not china)
We already has success engine line 176 & 123 & 88 & 61cc.....
Find more about our product here:http://www.flyinggiants.com/forums/s...ad.php?t=67373
And Here:http://www.flyinggiants.com/forums/s...ad.php?t=74744

Although we maunfactory gas engine for gaint scale aircraft but we(my father and me) were passion pattern pilot.
And I am Taiwan F-3A Champion from 2005~2013 also fly Asia Cup for Taiwan

MTK

Zi-Chun Lin,

Thanks for posting here-in. The qualifications you list imply that you know what sort of power we need for F3A Pattern flying. I hope you accomplish that goal.

Is you engine going to be a 2 cycle or 4 cycle powerplant? Either way, I am interested!!

JRgraham

My Feedback: (1)

Wow, thats huge News, Zi-Chun Lin !

I am curious how you decide at 40cc? Ihave followed your other engine threads on the Giants site, and it is clear you take great pride from start to finish with your work

Icant wait to hear more about this engine, myself!

flyva

Please...please make it rear exhaust! Not interested in side exhaust.

felkinsr

If the engine is smooth, I also have a need for a larger helicopter application.

-Richard

Bpar4

My Feedback: (1)

MTK, Since you are using the Tygothane tubing inside your tanks, what dimension tubing are you using? I have ordered the same and find it a bit too stiff to use in tanks of less than 500ml. For smaller sized tanks it requires an extremely heavy klunk. Thks. Bob

Zi-Chun Lin

The engine will be 2T and has side/rear exhaust
The one we want build for Pattern fly must be rear exhaust and we try to put sensor somewhere(not behind hub) so we can has norse ring there
Also we will has soft mount/norse ring / header/pipe available toghter!

MTK

I hope that you can complete the protypes in due time.....Unfortunately, The US market is likely all electric by then. BUT the rest of the world is a different story, judging from the letters I receive routinely, almost daily

Rear exhaust has certain advantages regarding installations but is not absolutely necessary. The OS33 has proven that. Which ever arrangement produces the best mid range torque and throttle response is the best one to go with.

Nose ring boss is a big deal. No current gas engine has any provision for nose support of any kind. There are ways around the current situation and I've figured out one way to do it, but it isn't the best way.

Something new,prompted bywork Rob from UKis doingwith his engine mounting, I am looking at bringing the rubber iso mount to the front of the engine thus eliminating the need for a nose ring altogether. The experiment hasn't started yet but the design is sound.Nevertheless, havingthe stand off mounting lugs near the front of the engine and closer to the engine's CG will facilitate that work

Regarding headers and pipes, I'd be very happy with just a header made for the engine. But It's going to be very hard toequal ES Composites pipe overall performance (power and weight). Overall weight builds up fast with this size powerplant. A complete set-up of less than 3 pounds (1362 grams) will be best. Itis doable currently with existing parts made for sport flying mostly, so a dedicated effort for Pattern first (and sport flying second) should be lighter...

This can potentially be a breakthrough for the few of us that prefer the smell of Avgas in the morning. Just hope there is enough market response tofully developthe effort

MTK

The material I use and sell is used in tanks as small as 8 oz and could probably be used in smaller. A standard klunk is used with even small tanks /short tube lengths. I've sourced genuine Walbro klunks which are heavier and will work with your set-up. Let me know if you need one of those

Tubing is sized at 1/8" ID X 3/16" OD. I've sold 100/s and 100's of feet of this material and everyone's response has been positive

vbortone

My Feedback: (2)

Hi Matt,

Where is the other thread about gas engines for pattern use? I lost it. It is about the pilot from Taiwan planning to build gasoline engine for pattern. I got a question: Why not consideration to small 4 cycle engines? I just got a trimmer 4 cycles and work incredible well. I think the 4 cycle have more torque at lower rpm that is convenient for pattern or precision aerobatics. Clearly the YS have been proving this fact for years. There could be an important detail that I am not aware. However, I think I need to ask the question. Probably you already tried or discussed. If that is the case, I apoligize in advance.

MTK

Vince,

Please look a few posts up. The guy you seek has posted here, in this thread. Did RCU lose the thread for you?

OS has just released their 40cc 4 stroke gassie. A few guys bought it from Tower and we should start hearing how it does in sport fliers hands. It's heavy at 1200 grams (engine only) and according to the specs develops only moderate power, less than the 33 2 stroke I use. SO I'm not going to jump on it any time soon.

My OS33 has gobs ofmid rangetorque, the best I've seen out of any 2 stroke in the 30-40cc class. Frankly, it's hard to determine exactly how it can do that and still use miniscule amounts of gasoline.......... About the only thing the 33 doesn't have compared to the YS175 is the great downline brakes YS's have. Sure, It is a little faster downhill but very manageable. I don't really feel rushed in the vertical down 4 point for example, or the figure 6 w/1/2 roll. I also realize that sincevery fewother than myclub mateshave seen my combination fly, it's hard for folks to get it from words alone..........So far, the 33 has delivered everything I've asked it to. I think enough of this powerplant to own several.

A really well thought out design of 40ccshould be a little better based on displacement.But do we really need to turn a 22" or 23" prop in Pattern? It would be great if it turned a 19x12 or 20x10 3 blader tho.

vbortone

My Feedback: (2)

Matt,
That breaking is the key of success in pattern. Clearly YS when to the process and decided that 4 cycle was the best solution for pattern. That is been proven tecnology. The new OS 4 cycle clearly is not designed for pattern. If someone wants to be serious about developing a gasoline engine for pattern for sure they should consider a 4 cycle with the features the YS 175 already have. Just cut and paste it. I am not expert in engines so probably it is impossible to do it with gasoline engines.

MTK

Vince,

It's the smaller 2 stroke capability at idle. The best it can do reliably in this displacement size is around 1750 rpm. Like I said, downlines are not a big deal in Masters and the OS responds adequately as managed. Downlines are not the killers of any sequence

In contrast, the piped DLE55 I am currently fitting in my new design, Delta, has a reliable idle at 1350. Coupled with the 20x12 3 blader, its brakes are better than any YS I've seen yet. I have to bump throttle up in most cases to clean up the downlines. Very slow.....Can hardly wait to get this combo in the air.....Later in summer.....

David Bathe

Please, if somebody makes a gas 4 stroke for pattern, don't do a YS clip and paste! It needs to be a no brainer, no service, no cost, no problem, no quirks, no maintenance jobby that just delivers the goods, without all the bells and whistles. It's that and exactly that, that makes gas F3A attractive.

MTK

David, well, there are several 4 stroke gas engines available today that have about the correct displacement But nothing is available at present in 4 stroke gasoline powerplants that has all the features pattern requires. The current offerings are limited by their lower power delivery and their heavy weight. Reliability is largely unknown and so is maintenance

The OS33 is an excellent powerplant for what we do. I also hear from Claude and Stephane in France that the RCGF32 is excellent.Of course,both are 2 stroke engines and are light weight. I know for a fact that the OS has been a practically zero maintenance engine (after the very early crankcase cover problem mine had) for several hundred flight so far. Reliability has been flawless. It's been "gas-up, fly, repeat".....All things considered, the best engine I've ever used in Pattern. When I have several hundred flights on my DLE55 / Delta I might change my opinion, but right now, it stands

flyncajun

LOL David,

We could call it "Miracle"

Don`t you think if that could be done YS would have done it already
We cannot rule out that it will take more effort for a gas 4 stroke to compete with a Glow version of even close to the same displacement.
This means .more stress lighter weight ,working on the ragged edge.
This is where reliablilty breaks down ,when you demand the absolute most out of anything it`s going to have reliablity issues. Getting a gas four stroke to even come close to what a YS 175 can do ,Dreaming! unless of course YS does it its not just about how much prop can you turn it`s way beyond that it`s about having the ability to use the power,brakes, midrange ,make noise, keep vibration down, available exhaust systems , airframes, props, ECT and the ability for the motor to do exactly what you want when you want it to.
evey time you fly no matter what the conditions are.

I`m not sure where the Myth came from that YS Engines are hard to mantain! I generaly get 500 flight without any issues when set up correctly,and have for many Many years , Learning how to run it so you can get 500 flights well that takes the effort.
the problem is we blame the Engine instead of our own lazyness sometimes I dare say the guys complaining about mantaining rarley see 500 flights in 3 years.

The Pure raw power of a YS is no Accident, it was developed to give the most power to weight of any engine in it`s class and has for many years.(in it`s class) Nothing can touch it, nor probably ever will. When it comes to power and reliability, and the utmost in controling, usable powerband a gas comparison is just dreaming.

Not to say there is not room for Gas engines in pattern I think Matt has blazed the trail ,But the Standard is the 175. Turn a 20-10.5 in 95 deg weather and 100% humidity at 7500 rpm and then get a reliable pur idle at 1350 and you will see what I`m talking about.

However just when Gas is close, YS just adds displacement

Just trying to bring some reality in the conversation.
Bryan

MTK

True that....I have been measuring against the YS175 as my benchmark burning 20%-30% heli.....How about 95 degrees, 85% RH, 20 x 10.5 apc, 7850 rpm, but 1750 rpm idle. Premium gas, Bel Ray MC-1 Racing Synthetic oil at 1 part to 50. Of course we are talking sea level.....Close enough? The idle is the tuffy in small gasoline displacement. The 55 drops idle down nicely

BUT I prefer Avgas 100LL because it doesn't stink andstores finein the jug practically all season and the next (if it lasts that long). Top end rpm is down a little but so what? Power is there for anything we do; let's not forget my current ride is a little fat (like its owner), at 11# 5. I am not overstating the fact that the 33 is a wash against the 175 in a practical way. (we don't ever fly full bore so what's the point of even discussing their top end. )

Point is both have all the power needed and then some, for the draggiest airframe we could throw at them Bring on the tripes