Prop size for YS 170DZ on a black Magic
 

Hi All,
Since I got some good help ony my exhaust question for my Black Magic retrofit of a YS170DZ, I thought I would ask for prop recommendations. I have been researching posts from 2008-2010 and most people were recommending APC props at 17X13, 18-11 and a few at 18-12, and 19-11. I am wondering if anyone has tried this motor with a carbon fiber (CF) prop on their pattern ship , although I suspect by the time CF props became widely available, folks had moved on from the Black Magic and the YS 170DZ

I have never been a big fan of APC props and am hoping someone has suggestions to map the APC props to CF equivalents or better yet has some direct experience with CF props on a 170DZ. I fly my 2M Black Magic for fun, I don't compete, but I do practice the lower sequences and am not interested in pushing my 170 to its very limits since I am just a sport flyer - Also plan on using 20% Cool Power heli fuel, as I use that for my other glow engines as well - I would reluctantly go to 30%, but prefer not to

Thanks to all who respond

Joe

I had pretty good results with APC 17x12 W & 18.5x12 WPN, but I was using 30% heli

Hope this helps

Adrian

Had a Black Magic several yaers ago with a 170DZ and I ran a APC 19x11. PowerMaster Heli 23.5% and I still run that combo today. Can't tell any diff from the Cool Power 30% heli to be honest with you.

I use a 19x11 with my 1.70

Hi All
Thank you for your help
I do have a question for you Maustin, when you mention Power master 23.5% , is that nitro or oil content? - if it is oil content, what is the nitro content? - I have never used Power master so am unaware of their lableling

Joe, 23.5% is the nitro content. My LHS ordered a bunch of this for a local heli guy and he bailed on the purchase. I picked up a few gallons to try since it was cheaper than 30% Heli. I can't tell the diff between the 30% and this 23.5% in my tuning but the heat of the summer may make a diff so we'll see. Oil content is still 22%.

17x13 on CoolPower 30% Nitro for me worked great.

Mike -
What hobby shop is this, and do they have more? I'm low on YS food. :)

Samano's Hobby Shop. Located in League City. I've been out of pocket for a month so not sure if he has any left. Was planning to stop by there this week and see if he has any left. Have you ever tried Rich's Brew Heli fuel in your YS? Not much info on the internet about YS flyers running this fuel.

Mike -
I have run it, with not pleasing results. Randy is local, and very helpful. But I just couldn't get that fuel to run consistent with my YS engines. I tried the YS 20/20 blend as well as the HELI 30% blend. The big issue is there was no consistency from gallon to gallon, I was changing needle settings a lot, and had idle problems with some. With the Morgan Cool Power or VP Powermaster I never touch the needles. I just fly.

Ok, that's what I was afraid of with Randy's fuel. Not in the mood to experiment too much.

I just spoke with Mike Samano at Samano's Hobby and he is currently out of the VP 23% Heli but he has ordered 3 cases due in next week. Price per gallon is unknown due to VP price changes lately but it usually runs around $4 to $5 cheaper per gallon than the 30%. I'm low on fuel too so need to resupply and practice for Jetero coming up in June.

Thank you!! I will give him a call as well. I hope to see you at Jetero!

I have a Black Magic and a YS 170 DZ. Currently I am running an APC 18.1 x 11. Also, the APC 17 x 13 is a good fit for the engine though it is slightly louder than the 18". The 18.1 is an 18" prop, the ".1" being a wider blade chord.
For fuel, I use VP Fuels 30% helicopter mix. Only because I fly YS 91, 96 and OS 105 helicopter engines and they all use the same; however, I think the YS 20/20 type fuel blend is more than sufficient for this engine.

Hi Chris
Thanks for the reply. I am currently trying out a 19X11 APC to see what i get - I am running YS 20/20 fuel. I used to fly helis as well, but got out of them - now its RC planes and U control glow. I am moving more and more back to glow and gas - getting tired of electric

Thanks again to all who responded

Joe

I've always used APC props on my YS's. Performance and low noise are excellent.

I used to run the APC 19 x 11 on my 170cdi with 30% nitro. I never had a non cdi version, but I think a slightly smaller prop may be better for that engine.

APC now have a range of carbon fibre props available, which are around 60 grams lighter and much more efficient than the glass props. With less flex, less throttle can be used and get better performance. It would be well worth checking if there is a size that would suit.

As mentioned above, using Cool Power I also just set and forget the needle.

I'm not sure if Rapicon fuel is available there, but i've been using it for about 3 1/2 years now. Like Cool Power, it's just set and forget also. I also think Rapicon looks after the engine better. I've noticed less wear in the bearings and ring.

Scott

Hi Scott
One of the issues I ran into with the 18" APC props is the hub size. When APC made the 19X11, it was specifically for the 170 DZ that I could tell, the hub size of this prop is smaller than all the 18" APC props and is much better sized for the 170 hub. I am not a fan of APC props and prefer carbon fiber prop where I can - It is expensive to experiment with CF props and given the small market for pattern props , especially on an engine not even in production anymore, choices here are limited in this case. My second choice was wood, and I also could not find a reasonable prop in wood - I am concerned about the 19X11 being too much prop. I have not yet flown the ship as it has been a very bust summer for me and I the first two times out had usual gremlins on new engine fit

I use 20% heli cool power in all my 4 strokes and am hoping this will work - I would rather not stock a specific fuel for an engine if I can avoid it

thanks for your help!

Looking at the APC web site, the hub size is the same for all the APC props in the 18" - 19" range - 1.25".

You won't find a better prop than APC for glow pattern, but if you're not a fan, then that limits your choice a lot more. Wood props are no good for YS, as the wood keeps compressing and it will always come loose.
If it were me, using 20% nitro, I would go for a APC 18.1 x 10.

Scott

I'm running a 19x11 on my 170dz with PowerMaster 23.5% nitro. What performance difference will a 18.1 x 10 give me?

Mike

I'm just saying what I would do if I had a standard 170 running 20% nitro. Performance depends on a lot of things. Airframe, altitude and flying style etc. But one prop doesn't suit everyone.
The 18.1 x 10 would give higher rpm and a bit less speed, but would give better climb performance.

That's only my opinion.
If you're happy with what you are are using though, keep going with it.

Interesting!! My only issue is there is a slight sluggishness on low end. I've contemplated modifying my throttle curve to compensate. Example is bottom of an outside loop maneuver I notice the need for more aggressive than normal throttle is needed to begin the upward half of the loop. I hate to think of a faster flying plane but I'll give it a try as I have a 18.1 x 10 handy.

Thanks!!

It won't fly faster.

It should give a smoother throttle transition, without the need for a lot of throttle to get the plane going from the bottom. Also should be able to get a more constant speed.
It will be interesting to hear how it goes.

Scott

Update: I did get 3 flights on the 18.1x10 this week and I do like the prop. The transition was smoother and the motor just sounded better. The mid range cruise speed did not increase as you stated! I'll get some more flights on it this week but so far so good.

Mike

Hey Mike,

That's good to hear 🙂

Scott