janch

I have seen new engine from MVVS. It is smaller brother from MVVS 58. It is MVVS 45. The power is excellent.
The engine turns with 24/9 JAs propeller 6450 rpm.
Model was Superstar 2,2m.

FreedomFlier

My Feedback: (8)

Dude!!! I got to get in on this!

Any more readings form the 85??.. I mean 58

How much does the 45 weight? There isn't a lot of info on the website yet.

janch

Hi.

The engine weighs 1400 grams.

famousdave

My Feedback: (61)

I am puzzled.. why would anyone spend $600 on an engine only to use a miserable cheapo prop like a Zinger for break-in??? I see this all the time and I just have to ask myself "why" ??

If you want a realistic RPM and a good break in DO NOT use those horrible Zinger or Zinger PRO props.. I see this mistake time after time on these powerful engines. You will gain 15% more thrust and a more stable midrange on a high quality wood prop like a MenzS or Bolly. Even the MSC or newer Bambulas are better, but still not as good as Menz or Bolly.

Save the zingers for the weedies or better yet - for stirring up you next can of paint! .. that is about all they are good for. Those props flex like crazy, flatten out at high RPM and VIBRATE. There is a good reason they are CHEAP. The RPM reading you see will be above where it should be due to the prop flattening out. I have seen several posts on RCU about those who had new ZDZ, DA and 3Ws boasting they got the rare engine that turns 9000 RPM!! a week or two later the same guys post that the engine bearings or con rod went south - most likely damaged by bench running (i.e. on the ground) at high RPM while using Zinger props. They simply don't provide enough load at high RPM and they provide too much load at low-mid RPM.


Try the Menz or Bolly - and then take your readings. You will be pleasantly surprised!
Even my G26 put out 13% more thrust on the same size/pitch Menz.

DP

Volfy

My Feedback: (23)

I don't much care for the regular Zingers, but the Zinger Pros work very well for me. I don't see anything wrong with using $20 props on $600 engines. I have just about every size of Zinger Pros precisely because they don't cost me an arm and a leg. This allows me to try a variety of different props on the engine/airframe combo to see which works best. Try doing that with the highfalutin European beech, and you'll have your wallet robbed blind.

Blaming engines burning up on the prop??!! Bad choice of prop size, perhaps, but the brand of prop causing an engine to burn up? Really?

famousdave

My Feedback: (61)

Volfy - You are correct in that properly pitching and sizing a prop is key, but take a 22x8 Zinger Pro and a 22x8 MensS and run them on a DA50. The Zinger will make more RPM, produce less thrust and have higher vibration... all bad things. The larger the prop the more critical this becomes. The really large Zingers are quite loose.

Some day you get a chance try flexing the tip of the Zinger Pro and the MensZ or Bolly props... you could use the tip of the Menz as a screwdriver...it most likely will break before it twists. The Zinger on the other hand .. twists like a popsicle stick. All wood props will flex some, but the zingers are notorious for flexing a lot.


We are all free to choose whatever works, if the Zingers work for you.. that's cool. I am not here to tell anyone what to use.. just passing on some 1st hand experience.

I do have to question the multiple prop approach though.. What is better - having many different pitches and sizes to try as "conditions change" to fit the airframe or having one size and pitch that is proven to provide maximum thrust and RPM with the engine one has selected?

IMO one $35 prop is better than 3 $20 props...

I have had the same 24x10 Bolly prop for over a year on my 3W-75. Yeah, its expensive at $65 but I only need one.
I have some Menz props that are 3 years old that have never been off the engine even though the engines have been on other planes..

I guess it depends on what you are trying to achieve.

DP

Volfy

My Feedback: (23)

The tips of propellors experiences no where near the amount of torsional stress as the base of the prop. The aerodynamic load acting on the prop is distributed along the length of the prop the same way an airplane wing is loaded. What this means is that the tip of propellors will experience much less twisting moment, therefore it can be built to be less torsionally stiff than the propellor base, where ALL the aerodynamic load acting on the entire prop blade accumulates.

When you twist the tip of the prop, what you are doing is placing a concentrated point load at very tip, which in no way resemble what a prop sees when it is working normally. It is easy to over-build a prop to resist ANY load, but it take good engineering to design a prop to be JUST stiff enough to resist normal flight load. This old axiom applies to almost all engineering endeavors, but it is especially true for all thing related to airplanes. Keeping the overall propellor weight down with good engineering design help reduce the rotational inertia, which in turn helps faster spool up and also helps reduces vibration - which is one of your chief complaints.

I, for one, NEVER judge the validity of a product by its price tag. Far too many other factors are involved in setting the $$$ amount than simply its performance. Neither will I tell somebody NOT to buy the more enpensive one even if there is a less expensive alternative. Sometimes people are perfectly willing to pay good money for non-tangible benefits, such as style, brand prestige and exclusiveness. And that's just fine by me.

calnev4bob

the 24 /12 prpp is a bolly. If you red my thread past the 24/10 zinger there is a , after zinger. and the 24/12 is crbon fiber.

calnev4bob

Also I tiep and spell verie badly

famousdave

My Feedback: (61)

I don't disagree with the $$$ thing. There are those who will buy the more expensive thing just because the perception is more $$= Better... many cases more $$= sucker... especially in this hobby. I'm not sure it is the case with props.

The twist test applied to the entire blade.. I guess my post made it sound like I was only paying attention to the very tip.. that said, you bring up very good points, but again, the thrust numbers should be the telling truth. I don't have the numbers but for someone like Dick Hanson or Ralph at RCIgnitions it would be cool if they did some prop / thrust / RPM comparisons with a controlled test setup.. say a BME ZDZ and DA on various brands of props of the same pitch..

I for one have definitely noticed and measured a difference on a fish pull scale between Bambula props and Menz, but without the data or a decent measuring tool its just hearsay! Fish scales are not real accurate and we all know what happens when we say we used one to prove something !

I fortunately, go through very few props. I have damaged more from banging them on doors and tailgates during transport than I have from flying / landing, but that does not mean I LIKE spending $45 - $60 on a prop even it does last a long time. If I could find one that flew the same and was less costly you bet I would be all over it... unfortunately, to date, I have not. I have had very bad luck with Zinger and Bambula props so I won't use them.. now if there was data showing otherwise then maybe I'd be open to trying again.

Sorry, I hope we haven't hijacked the original thread!!

DP

Volfy

My Feedback: (23)

DP, I was thinking the same thing about hijacking this thread. I hope our exchanges haven't been taken as such. Because props are such an integral part of engine thrust and power production - and this thread IS about HP claims of the MVVS 58cc - I think the relevance is there.

It's easy to get wrapped up in the pissing contest about who's got the better equipment. I, like the vast majority of RCers, am just a sport flyer and don't compete. I don't need to wring every last ounce of thrust out of my engine, nor do I need the top of the line fire breathing featherweight sexy polished titanium engine that everybody wants to talk about here on RCU (yes, y'all know which ones I am talking about). I may want to enjoy some serious fun with some serious equipment every time I go out to the field. But it is still just for FUN. Period.

The best of the best is definitely not required to have some serious fun. But I do understand that owning and bragging about it can also be seriously fun. I wouldn't know it, so I won't argue with that.

By the way, speaking of MVVS 58cc. I was just at Morris Hobbies this afternoon. I saw the one NIB MVVS 58cc Robert had there and it is a beautiful machine. I was told I need to get on the waiting list like everybody else. Hmmm... I guess I might just have to give MVVS Canada a call...

Waco

My Feedback: (265)

If you want a MVVS 58 give mvvs canada a try, I just order one and got it 4 days later and at a cheaper price the Morris is selling for and no waiting.

famousdave

My Feedback: (61)

Hmmmmm... I might need to make a call to Canada too!! That MVVS might just be the ticket for my Velox if it ever gets here!

Volfy - I totally appreciate the fun factor.. some times us competitive flyers get caugbt up in the BS and forget the fun stuff!! I'm with ya!

Fun first!

DP

David_Moen

I have an MVVS 58 on a BME Edge waiting for a maiden. The engine has been on a Lanier Cap, equipped with floats built buy our demo pilot, it was fun, but that model was re-kitted at the end of the season. BTW, the 58 fired right up after we pumped the water out of it!

I too am interested in the Aerotech Velox, I'm thinking of putting one of the new 45's on a cannister in that one. I've got 116cc twins coming as well.

janch

I am sending you samwe information.

http://www.poletovani.webzdarma.cz/MVVS/45.pdf