Old Timer 3 Channel Power systems

Gregor77 · February 25, 2013, 10:43:03 AM

I need some assistance from some of the more experienced with Old timers... I just restored the big 3 channel and I need to make sure I don't over power this pig. It's 8 feet WS and about 6-7 lbs. I have 800 watts in it right now with a 17X10 prop. Amps are not bad at 50 full open. Mind you I am running 5S.

Would I be better off dropping the pitch or reducing the size? I don't really need a speed demo in this case... lol!

piker · February 25, 2013, 01:28:30 PM

I've never had an old timer, but I would assume light weight is more important than power, generally. But I guess if you can get a good amount of power while still maintaining a light wing loading, you'll be good. Old timers are/were competative models that would have a limited motor run to climb to altitude. Vertical climb-outs were part of their repertoire.

Tomahawk · February 25, 2013, 02:49:53 PM

A lot of it depends on how you plan on flying the Oldtimer.

One thing you don't want is speed or you will be fighting a climbing model. They do climb very well. Personally I use a low pitch, large diameter prop. for example 13 x 4.

Like Rob mentioned, these planes were designed to quickly climb to altitude and slowly glide down after the motor shuts down and hopefully achieve a long flight time. This was all done free-flight (no radio control) One must realize this when adding the radio assist. If you want to drive the plane around like a tractor in the sky you will be fighting the original characteristics of the oldtimer. It can be done but you will have to play around with the downthrust, wing incident and maybe cg.
I do fly them around like this but mostly take them up and glide down looking for thermals.
Most oldtimers have a very low wing loading which make them thermal quite well.
Here is a video of my Feather Merchant. 72"ws 2.5lbs and a wing loading of 8ozs/sq. ft. I have found you can fly on much less power than a sport power system and much longer. It runs on a 3s 2200mah lipo at around 25amps. 13 x 4 prop and flight times around 40mins+. I don't fly that long and usually take breaks.

Chris

Feather Merchant 72" wingspan- Spirit of Yesteryear

Gregor77 · February 25, 2013, 04:21:40 PM

hey, how many of us actually have some of these old girls? I am assuming a flew... $:-\$

gordonbw · February 25, 2013, 08:34:05 PM

In my experience with old timers (Astro Viking and Buzzard Bombshell) the short nose moments on these models makes balancing a challenge. The SOY kits are designed for heavy brushed motors and Nicads. I'm planning to buld another Viking and will probably have to use a bigger motor than strictly necessary just to get the CG right.

Tomahawk · February 26, 2013, 02:08:29 AM

Quote from: gordonbw on February 25, 2013, 08:34:05 PM
In my experience with old timers (Astro Viking and Buzzard Bombshell) the short nose moments on these models makes balancing a challenge.

You have to be aware of the short noses on these old gals. My last build of the Plecan Falcon was one. I was looking at adding almost 2lbs to the nose, to just achieve the free flight cg. I elected to lengthen the nose which allowed me to hit the cg without such a weight penalty.

Chris

Gregor77 · February 26, 2013, 06:21:59 AM

Chris. That is a good looking plane.

Tomahawk · February 27, 2013, 01:39:58 AM

Quote from: Gregor77 on February 26, 2013, 06:21:59 AM
Chris. That is a good looking plane.

Thanks for the compliment! I should mention those pics were taken before the nose extension.

Since Rob likes float planes. Here is an oldtimer float plane from around 1945. It is on my to build list. Called the Swoose.

Chris

Gregor77 · February 27, 2013, 08:50:30 AM

That would be great for some flights on Frenchmans bay! My old timers is good to go now. I added some down thrust and the power system seems to be OK for the maiden flight. Just the weather is the current issue. I am also planning on installing some skii's on it.

The pilot figure will need some work. I am planning on Making a cartoon character from the 40's as a pilot. Pink Foam and hot glue are always my friend for this kind of stuff. Anyone have any suggestions. I was thinking the guy with the burger? Mr Mugoo? Before my time.. But not by much!

Gregor77 · February 27, 2013, 08:53:19 AM

Sorry.. Whimpy...

piker · February 27, 2013, 10:28:09 AM

I'm sure whatever pilot you come up with will be awesome

Hey Chris! I know that plane (from the magazines). I still have a MAN magazine (I think) with an article on a modern (early 90's), RC version of the Swoosh. It certainly is a pretty plane with that gull wing.

Robert

Tomahawk · February 27, 2013, 05:02:17 PM

You are correct. Nick Ziroli liked the Swoose so much, he enlarged it and added control surfaces. Also flattened the wings a little and squared it up a bit for easier building. I think it was published in RCM.

I look at the original Swoose and think that this must be a one flight plane. It was freeflight. Landings would be interesting as it could be way out in the lake or not so great if it landed on the dirt. Just wonder how many returned in one piece.

Here is a pic of the Ziroli version
Chris

Tomahawk · February 28, 2013, 01:28:52 AM

I just looked it up. You are right again Rob. It was published in MAN, the October 1989 issue.

Chris