Has anyone used the OS .15 CVA engine before? I'm thinking of using it in the Mini 3D from Extreme. What I really want to know is how loud it is...kind of a tough thing to judge, I know....and this post may not get any responses .

I'm looking to fly this plane in a small field a mile away from my home where some guys are flying strictly electrics. I'm trying to decide if I'd become a nuisance or not. I know that .049's can have a piercing scream and I don't know if this little engine would fall in that category. I wonder how this engine would compare to say a 46FX? (which I consider to be fairly quiet).

I've emailed this question to a guy in that electric group, but in the meantime I was wondering if anyone here had any insight. If it's a problem, I'm going to have to setup the plane as an electric, but that will be something new for me...I'd rather just use the glow engine.

Yes it will. Dont have one myself but have seen one. In Db terms not loud, quiter than a 46 FX, but does scream, as all small engines do to an extent. An exhaust deflector helps a lot.

If you plan to fly with guys who only fly electric, I would ask them first if it is ok or not. If not, see if they will help you get an electric set up. If they don't help, probably not worth joining them anyway.

I have a combat plane with a LA 15 using the SSC (blue) MA prop. It is annoying to even me. I was considering the 15cva and an APC 10x3, but don't know if it would be any less obnoxious, or if the prop would even work with that engine.

Thanks for the feedback guys. Looks like my concerns were at least a little valid. It's not really a club per se that I'm looking to join, just a handful of guys from a couple of different clubs using a smallish public city lot. It's real close to my home so it would be great to plop in with a really manuverable plane. It's not too far away from a trailer park so maybe the noise could ruin things...or maybe not...I'll wait to hear from them anyway (these are people I already know).

But your answers are making me think I should investigate going electric with that plane. Extreme RC tells me they think that RCU will be doing a review of the Mini 3D with electric power. I may hold out for that to see what's a good setup (since I have no electric experience). Thanks again.

Edited by Thumbs: I've since heard back from one of the folks flying that field. He says they fly helicopters there so why not use a small powered plane? Hmmm...I just may be using the OS afterall. If I do I'll be sure to use an extension as suggested.

I'm getting the Mini 3D and will put the OS .15 CVA in it. I got the motor used - NIB on RCU for $95. Tower sold out the Hitec Flight Pack w/ the 555 and (3) HS 81s, but Horizon still has them.

I'm not familiar w/ the noise, but the .15 looks great on the Mini 3D video...

I have a OS 15 CVA on a Lanier Shrike with a Macs tuned pipe and its not to bad. Now the electric guys might not have the same opinion?

Well I bit the bullet and ordered the OS .15 CV-A, along with some APC 9x4 props (as suggested in the Mini 3D video). That part of my package arrived yesterday but I have a slight problem. The prop holes are bigger than the engine shaft! This is a new one on me. Have any of you folks had this problem, and if so, how did you solve it? For the moment the only thing I can think of is to find some spinner spacers that might fill the gap, but is there something readily available, or a regular technique for this that I might not know about?

The best thing to use is brass tubing as a bushing.

K&S makes tubing so that each smaller size fits exactly inside the larger, so with one or two small pieces you can fix the problem.


Leonard

Great idea....thanks Leonard!

Bingo!
If you look at the back side of your APC props you will see a recess that will accept a reducer (spinner reducer). works great!

Good luck

You know, having been in this hobby for only two years and I never put together what the APC recess was about. Now I know .

I ran my engine today for the first time and it's really not too bad at all. I'll bet it's smoother and therefore quieter than the LA version (not that it's super quiet mind you). I started this hobby with an LA 46 and then noticed how much quieter the 46 FX was when a buddy got one. The same thing may hold true here. I think I'll be happy. Thanks again to all for the input!

Chuck

Chuck,
If you want to quiet it down, make a small mousse can mufler, that should make it almost pleasant to listen to. I bought a 25LA for my Mini3D, which I hope to tomorrow, shipped Monday, and 4HS81 and 1 HS55.
DKjens

That should have given you a hint that maybe a 9x4 prop is a little too big for that engine. The 9x4 is typically a 25-size prop. Right out of Tower Hobbies: Prop: Break in: 7x5; Sport: 7x5, 7x6, 8x4, 8x6, 9x4; Aerobatic: 8x4, 8x6. For your application, you don't necessarily want the biggest prop available in its class.

I started mine out with an 8x4 Master Airscrew and found my combat plane was not faster/responsive than others running with Magnum XL .15s. I switched to a Master Airscrew 7x6 and that brought the engine to life.

BTW, as 2-stroke engines in that size go, the OS .15 CV-A is a very quiet engine. It should not bother anyone, least of all, other flyers.

Have a buddy who had a Sig Wonder and CVA 15. Holly ! that thing went!!!

Well I've run one tank through the engine and it's not bad for the noise. At the very least it won't be an issue at the little field I'll be flying at. It's a nice engine.

I have yet to finish breakin but I did get one reading of about 11,500 rpm using that prop (9x4). For the most part I was running it very rich and under 11k. We'll see what happens on the next tank when I get a chance to run it again. If flight tests suggest that I should change props I will...but I have no desire for speed with this plane so I certainly won't change the pitch. It's a new experience for me to run an engine of this size. Eventually I'll find what combination works best. I appreciate the suggestions. Still, I was impressed with the video I saw so the 9x4's gonna be my starting point. Someone in another thread suggested that the combat fliers are using different props, but this isn't going on a combat plane it's going on a Mini-3D. The slower I can get this thing to fly the better (but there could be an 8x4 in my future...I'll at least have to try it).

Im sure the OS 15 CVA and 9x4 set up will be awesome on that Mini 3D. I would like to hear how you like that plane if you have the time!

Good luck

Oh, I'll find the time...I just need the plane first . It should be in transit now. Then I'll have to get it put together and get a decent day to fly. It's gonna be a good week before that happens I'm sure. There's another thread strictly on the Mini-3D going on and the reports of that plane are starting to trickle in. So far it seems to be living up to it's promise.

Edit: I forgot to provide a link to that forum...

http://www.rcuniverse.com/forum/Mini...1286600/tm.htm

Thanks
I'll check out that other thread. A flying buddy in town just recived his but i think it will be awhile before he gets around to putting it togther. I am waiting on there 68" YAK but know thats aways out.

A buddy of mine is sending me a mousse can muffler to try out on the .15 CV-A. He claims an increase in RPM'S around 1500-2000. I'll let you guys know what I find out.