Flyboywbl

Hi guys. I finally am going to get to build the TopFlite DC-3 kit this winter. I flew my Twinstar ARF this summer and it's still intact. Had a few engine out landings no problem. I think i'm ready for this interesting albeit long build. Oh well it's a long winter. Any way i'm trying to decide what four strokes to use on this. I was thinking Saito 40's or Magnum 52's. SOOOO sad that os discontinued the 52 surpass. Now you need to spend damn near 300 bucks for one of their new 56's. Really REALLY dumb. why mess with a good thing? any way. what do you guys think. I want this thing to be as scale as possible. I feel like two 52's is way WAY too much juice. I also live at 4500 feet. I think the Saito's look better and i think they are more reliable than magnum. Plus they are only 10 bucks more than the magnums. I just want to make sure this thing has enough power incase of an engine failure.

Also i will be putting twin sync on this.

Could i get away with two OS 30 Surpasses? I have one on my t-craft 25 kit and to be honest it's not enough mustard. I thought the RCV in cowel engines are way cool. too bad the smallest size is a 60 thats probably way to much.

I thought about the wankel 30's but i don't want two spend $860 on engines alone.

Thanks for the advice!

-Matt

GaryHarris

Magnum 52s. Great engines. I saw this video and it made me want to build this plane.

http://www.youtube.com/watch?v=v4yFLXbj1VM

aerowoof

I have os fs-48 surpasses on mine

Insanemoondoggie

I always wanted to build this kit, but the retracts are soooo spendy .Magnums 52s are great engines and would work. I also think the Saito .40s would fly it ok. Does the kit build tail heavy or nose heavy ? Might want to consider that in with your engine selection.

DavidAgar

My Feedback: (108)

My buddy has OS 40 4 cycles on his and it fly's the plane real well. I would not think anything smaller that 40 4 cycles for the plane would be good. Good Luck, Dave

Flyboywbl

Hey guys thanks for the advice! I think i'm going to go with the Saito 40'S i looked at some other threads and there is a guy who uses 26 os four strokes. I sure 30's would fly it but i think on one engine we would have some problems. I think with 40 two cycles the thing would be way to fast for scale flight. 25FX's would fly it scale like but would not sound scale (i run these slightly modified on my combat planes and needless to say they turn about 18,000 RPM...Not to scale sounding). I'm betting the Saito 40's will turn 8-10,000 rpms but you will get the great four stroke sound.

Any suggestions on three blade props?

Thanks again!

-Matt

aerofly0610

I got 2 os 40la's for 60 bucks off ebay for my tf dc-3. Otherwise I would get the 52 magnums, but I'm too cheap haha.

jaka

Hi!
I use OS FS.26 four strokes in my Marutaka DC-3 (span 211cm) which is in the same size as the Top Flite DC-3.
Plane weights 3,6kg ready to fly and flying speed is very scale like at 1/3 throttle.
Any engine over .25 is way to big and will produce a plane that flies too fast . So go with either .30 four strokes or .20-25 two strokes.

My DC-3 is very easy to handle and fly like a 2m span sailplane.
It do this because it is built light and have 1-2degrees of Wash-out in the wing tips (just like the original).
I use custom made 3-blade carbon props (10x4,5) which my OS FS .26 turn at around 9400-9900 rpm using 5% nitro and 15% all synthetic oil.

buzzard bait

Jan, how did you do the metal finish on that beauty? I've really admired the pictures on various threads. What did you do for landing gear?

Jim

jaka

Hi!
Covering is just ordinary Chrome Oracover (Ultracote), wet sanded with 1200 paper, on a sheet of glass to obtain that aluminum finish.
Fuselage is covered by appr 100 small pieces of rectangular plastic film sheets to get that real alu look. Some complex areas are covered by using aluminum duct tape. Elevators are covered with Oratex (same as Solartrex ...but a little better). Side rudder is covered with silk and dope and spray painted with "Sikkens" 2-part Auto-cryl lacquer.
Landing gear is just piano wire sweet soldered together, made to function like the original (not exactly scale though).
Landing gear mecanics is 30 year old Giezendanner electric retracts.


By the way...It takes off in just 20-30m and make large loops and rolls with ease.

buzzard bait

Lovely. The combination of a good scale look with light weight, appropriate power, and enjoyable, scale-like flight is a wonderful and rare achievement. Thanks,

Jim

drube

Beautifulplane jaka!

PeteP65

Hi Jan, Thank you for all your posts. Very helpful. I just started a Top Flite DC-3 and am planning to use the chrome oracover.
I would like to know how you prepared the balsa before covering. I do not want to use fiberglass cloth as I believe it to be too dangerous to sand. It does not appear that you used cloth. Does just using oracover panels over balsa compromise strength?

I also noticed that you are using header tanks and not using muffler pressure. Would you please explain your fuel system?

Thank you, Pete

Flyboywbl

Well after over 5 years, and two moves across the country, I finally bought the DC-3 Kit from Tower Hobbies with the Robart Reracts. The plan will be to use 2 magnum .52's. I will try to get the engines this summer and get them broken in on a test stand. The build will have to wait till the fall/winter.

Flyboywbl

Well that bought the magnum .52's. I'm halfway through a Sig Hog Bipe build and once that's done, I'll move on to this bad boy

jaka

Hi!
Any engine over .30 will be way way too much power and too heavy/cumbersam. If you use .52 Engines be it four or two strokes your DC-3 will fly like a pattern plane and will fly real bad!
My Marutaka DC-3 is powered with two OS .FS .26 engines and the power produced is soo good that I only use full power at take off. Flying is done on just 1/4 throttle. Weight is 3.6 kg.

Flyboywbl

Unfortunately the .52 magnums are all I could find. OS does not make 30's and 40's anymore. It's just gonna have to be over powered. I'm confident of the throttle is managed properly it will fly in a quasi scale manor. It is a sport scale plane after all. Also, the manual suggests .52's if this is your first twin to have adequate power, should you lose an engine.

jaka

Hi!
OS FS.26 and .30 could be found on eBay!
Unfortunately throttle management is not a viable/practical solution in a scale plane like the DC-3! You still have the weight and not to be forgotten ,the explosive power developed when you give full throttle (in an emergency situation that will make the plane spinn and crash).
You will also find it difficult getting the right props for a large .52 engine.
For the .26 and .30 there are scale props available that are suitable for both the Marutaka and Top-Flite DC-3.

Flyboywbl

My friend has built and flown this aircraft with OS 52's and it flys just fine. The magnums are less powerful than the OS's. Also, with twin sync, if one engine quits, it retards the throttle on the good engine. Then you can slowly add the power back on the good. Again with good throttle management, it will fly just fine. If this was grossly over powered, why would Top Flite recomend .52 four strokes?