Aresti-RCU

My Feedback: (1)

The last weekend I saw a DA50 nicely stuffed into the nose of a Scandalous bipe at CA Mode's boot in the WC site (I would try to post a picture later today when I am home). The plane is supposed to weight about 5.6 kg dry mostly from the reinforcement of the fuselage. It was Marcello´s own electric bipe that got converted to gas. I guess 0.3 kg should be the weight difference between the electric setup (batteries, ESC, prop, etc.) and the gas one, and another 0.3 kg the reinforcement.

I am here contemplating a carbon fiber bath to the nose to my glow Genesis and hard mounting that cheapy chinese 50CCer as my official practice plane. Ready to fly weight should be about 0.4-0.5 kg heavier with the gas (accounting for the increased weight of the engine less the glow mount and smaller fuel tank)

Do you guys think it would be doable? Would the gas engine tear down the plane? Would the Genesis take the extra wing loading?

vbortone

My Feedback: (2)

Yes, the vibration level is so high that will destroy your plane. I had the experience with an Abbra and the ZDZ 40. The ailerons fluttered really bad and we were lucky to land the plane. Installed the hyde mount and the problem was solved. The reduction of vibration and noise was just hard to believe. Here is a picture. The weight was 5 ounces over the limit but we were using 3 blade carbon prop that was too heavy. I think a wood prop is the solution in that particular case. I don't know what is the difference in weight between the ZDZ40 and the DA50. I guess that the DA 50 is a little heavier.

Regards,

Vicente "Vince" Bortone

mmattockx

I assume you are thinking of the DL-50? It is quite heavy for use in a pattern plane. Lots of power, though. I would suggest maybe trying a Brillelli 46GT instead of the DL, it is significantly lighter and would be a better fit. Less power, but it should still have lots for your uses. Virtually the same price and great customer service from Scott.

http://www.scottellingson.com/brillelli_engines_011.htm

Mark

Magne

What about the "new" ZDZ 40 RE F3A?
It weighs 2 lbs 11 oz incl. the ignition, but without header and pipe.
For comparison, the Brillelli 46 weighs 56 oz (3 lbs 8 oz) including the noise enhancing thingy on the side, which you presumably wouldn't want to use in a pattern model.
ES Composites pipe is 4 oz.

This is probably the lightest gas set-up with enough power for F3A.

Magne

mmattockx

I believe the goal was "cheap". The F3A could be called a lot of things, but cheap isn't one of them... Not at $600 per.


Mark

onewasp

{Quote}
----Not at $600 per

{Quote}

True, but still less than the DZ170/160 and then you have the fuel savings to consider, plus about one half (or less) fuel weight on board-----lots of possibilities.
NOT however in the DL price class.

Perhaps if we re-badged the ZDZ 40RE-F3A to DA
Then, if history is any gauge, we would have a DL 40RE-F3A in a matter of 60 to 90 days[]

Apparently ZDZ just doesn't 'cut it' with the China IC folks[X(][]

Bob Pastorello

My Feedback: (198)

mmattockx - I have a DL 50, stock muffler (LOUD, LOUDDDD) in a Goldberg Obsession. Although not a "pattern airplane", because it is both oversize limits, and over weight limits (and noise limits).... it LOOKS like a pattern airplane, sort of, and certainly flies with a lot of precision.

The resonance of the airframe where the vibes are the worst is just above idle.... at "cruise" (about 1/3rd stick with a 22 x 8), it is pretty tolerable, monitored by on-board video. Not much trembling going on during cruise.

It was very inexpensive, SIPS fuel, and will last a REALLY long time.
I have more detailed info available, PM or email if interested.

onewasp - it's pretty awesome power to weight, and the cost per flight is only a couple of cents...

onewasp

I think we may be looking at a profound 'P' effect!

EXCEPT that in this case the 'P' is for the plane rotating at the end of that prop/engine set up.
Are you quite certain that the prop doesn't stand still while the Plane revs?[X(]

Bob Pastorello

My Feedback: (198)

Yes.
Full throttle vertical takes some opp. aileron and lots of rudder.
It's fun, though.

What I do like about this combo is the total performance envelope. It can slow to a crawl and still be stable because it's got so much area. Of course, that isn't your friend in the wind.

But I have this to do precision flying; gotta get it some way.

cmoulder

aerobob, do you still plan to try the 3W 28cc?

Bob Pastorello

My Feedback: (198)

Yep. THat will be after Christmas, before Tax season, and will do a header/canister configuration.

The Peakmodel 26cc rear-intake proved to be "okay", but turning a AP 17 x 8 at 7400 ain't gonna make it. I know the 3W does a lot better, with more prop.

dwaynenancy

My Feedback: (62)

Bob, why did you quit using Brillelli engines? I have been impressed with Scott's help with problems. Dwayne

Bob Pastorello

My Feedback: (198)

Haven't "quit". Have his 366GT in my big Yak, works just fine.
DL has a better footprint/weight/cost benefit for me in other applications.

Brillelli's are great engines, Scott is an excellent guy.
DL's are great engines, Bob K. at DLUSA is an excellent guy.

Anyone that knows me knows I try different things and like to experiment. When I choose something "different", it doesn't mean the first thing was "bad" or "defective", Holy Cow....

cmoulder

Hey, Bob, keep doing it this way. You're living our dream, man!

As you may recall, I have the Brillelli 46, and had it in my H9 Extra. Had a small problem -- Hall sensor wire due to my improper installation most likely -- and while waiting for the part I installed the DA-50, just for the heck of it. Brillelli was perhaps the perfect engine for the Extra, but I wanted to experience the DA-50. Great engine also, but at a premium price, and not really needed for every application. So I'm going to be working soon on a RCGuys Super Decathlon, and the Brillelli is going into that.

Magne

Agreed, and I understand that. But the difference between using a ZDZ 40 and a DA/DL 50 may (or may not) mean the difference between meeting the weight requirement or not, which again means the difference between having a model solely for practice (as was stated in the original post) or having a model that can actually be taken to a competition, if only as a back-up model. The extra few hundred dollars may be well invested, in my opinion.

Some 10 years ago I scratch built a (comparatively slim) balsa model using the 3W 24cc engine. (This was the predecessor to the 28, I believe.)
The model weighed just under 5 kg, and flew OK with a 17X13 prop, however not really powerful enough for F3A in my opinion. I don't know much about the 28, but looking at 3W's specification, they say 2.75 Hp, recommended propellers 16x10, 18x8, 18x10, 20x8.
The ZDZ 40 F3A is specc'ed to 4 hp, recommended propeller ZDZ 20x12. (7000 rpm+ reported with ES Composites pipe and this propeller.)
There appears to be a significant difference in power.
(I do have the ZDZ 40, and will try this as soon as time allows in an own design model.)

Magne

cmoulder

Magne, the ZDZ 40 you have is the "F3A", correct?

For gas, it appears the only design that is going to work for pattern is rear carb-rear exhaust. I hope to work on putting together a gas pattern model next year, and so far this appears to be the only engine that fits the requirements. With the proper header and a widebody-type fuse, the side-exhaust 3W 28i might fit under a pattern cowl.

I have not scratch built before, but if you have plans I am motivated enough that I'd try my hand at it, especially if I could find somebody to laser cut the ribs and any curvy formers... Actually there is a gentleman named Dave at Littlebirdz who I believe could cut them for a reasonable cost.

Magne

Yes, it's the F3A version. It weighs 2 lbs 11 oz (1220 grams) with the ignition, exactly the same as 3W are quoting for the 28.
(Although ZDZ "forgot" to include the weight of certain bits and pieces, such as the removable prop shaft, prop washer etc.)

The model is my own design, with a molded fuselage. This was originally made solely for electrics, but I think a ZDZ will also fit. Access to the engine will be a little unusual, as the canopy extends right forward to the spinner. (This, in my opinion, is ideal for electrics, where you have full access to "everything" from the top.
Pictures taken last winter of electric prototype No. 1. Yippeee, that white stuff is coming soon....[&o]

Magne

cmoulder

Very innovative! Good thinking.

Living in Norway, I'm sure you have flown airplanes with skis. Last winter I flew a small model (Fliton Extra)with a .91 4-stroke with skis and was delighted with the experience. I can't wait for snow this year. Soon I will have a 98-inch wingspan Super Decathlon and it will have skis for winter flying. I will use a 46cc Brillelli gas engine it it. 'Ground" handling with skis is excellent!

vbortone

My Feedback: (2)

I agree with Magne. I had the opportunity to fly the Abbra with the ZDZ 40 non F3A. Based on that experience, I believe that the 28 cc gas engine won't be powerful enough to do the AMA-Masters or F3A schedules. It could be OK for lower classes.

Vicente "Vince" Bortone

cmoulder

Hopefully more gasoline engine makers will now turn their attention to this niche.

I have noticed also the new Saito FG-36, but it doesn't seem a 4-stroke gasser is intended at all for pattern. Perhaps for WWI scale models?

onewasp

hmmmmmmmm or tail heavy 12O sizes !

Hans Meij

In the FMT, leading German magazine, there was a interview with the EVO-manufacturer. Besides a 50 / 100, a 33cc F3A engine was mentioned to be in devellopment.

Kema

Captured from Spanish forum

http://www.acro3d.com/public//dscn9565_285.jpg

Maybe this replaces my MVVS 26

Hans Meij

Thread seems to be 1,5 years old. I would like to know how close to production this engine is.
http://www.acro3d.com/foro/viewtopic...r=asc&start=30

esamart

Although ZDZ 40 F3A might have enough power for FAI F3A it wont easily pass sound limit. Magne, please run yours side to side test with YS Dingo etc. I believe hard mounted bench test would give enough information is there any sense to start developing softmount.

As we know propeller sound of current electrics is already guite high. With large gas we have loud exhaust too and airframe resonation as well. Intake sound won't be bad because of carb location.