Author Topic: OS35S Max III (Read 2813 times)

ash · « **on:** February 14, 2006, 10:29:31 PM »

I've just picked up another nice OS35S, now I have two earmarked for a Classic stunt model of some kind.

One is in fairly good condition but needs a clean, the other is possibly on the downhill slope of life. The three designs I have in mind are the Novi 3, and Stunt Machine (both of which originally flew with this engine, I believe) and the Hooptee, which ran an OS29.

In the modern context of "there's no such thing as too much power" how much of a ship can an average example of these engines gracefully drag around with ease?

RandySmith · « **Reply #1 on:** February 15, 2006, 04:28:23 PM »

The OS 35S is generally most haapy with a 480 to 550 sq. in. size airplne.
However people have flown larger and smaller ones with that setup.
This will depend on weight and how easy the plane pulls.

Randy

ash · « **Reply #2 on:** February 15, 2006, 06:19:55 PM »

Thanks Randy. Looks like my Classic dreams are in/over the upper end of that range. I do like the idea of authentic engine/model pairings, so I might have to build light and tip the nitro can a little longer if I want to keep it useable!

I guess first thing to do is clean up and run the engines to determine which one is best able to do the job.

Marvin Denny · « **Reply #3 on:** February 15, 2006, 06:32:57 PM »

My Novi III flew quite well with a Fox Stunt 35 on it. Well enough to take a fifth in advanced one year at the Nats. It is around 600 square inch wing area and mine was a bit po the obese side.. The designer, Dave Gierke, had an OS 35 in his.

Bigiron

RandySmith · « **Reply #4 on:** February 15, 2006, 09:04:26 PM »

Hi Adrian

I would go for whatever plane you want for the 35S, I am sure you'll be happy with the run.

Hi Marvin, yes I agree as I said in my post others have ran a litle larger plane, and the Novi lll is a very good plane, it also is not a hard plane to pull.
I have seen people flying Stilettos , Chipmunks, The Larger T-Birds and others with the 35s.

Those were among the best engines of the late 60s ,early 70s

Regards
Randy

rustler · « **Reply #5 on:** February 17, 2006, 01:28:14 PM »

Just curious about the III in your heading. It seems clear you are referring to a Max-S35, but if it is a Max-III 35 it's a different animal so far as stunt is concerned.

ash · « **Reply #6 on:** February 17, 2006, 04:00:16 PM »

A very good point, Mr Rustler. I have two and one was advertised as a Max III when I bought it and I never knew there was a difference. On closer inspection, they are both labelled 'MAX-S' on the transfer side. One is stamped '35' and the other I have just discovered as I type this is a '30 RC', which changes things a little bit. They are externally identical, so the option possibly remains to get a Bristunt 35-S ABC P/L set for the 30 assuming its a simple bore difference. Either way, methinks this is just the excuse I need to build BOTH a Hooptee and a Stunt Machine...

Thanks for making the distinction, Sir.

Bill Mitchell · « **Reply #7 on:** February 17, 2006, 08:01:29 PM »

You can in fact get a .35 piston, cylinder, wrist pin and head and make your .30 a .35 but I would ask why bother. The .30s run great, have nearly the power of a .35 and would be better suited to some of the smaller models that people like to stick a .35 in.

Bill Mitchell

Bill Little · « **Reply #8 on:** February 17, 2006, 08:38:52 PM »

Quote from: ash on February 17, 2006, 04:00:16 PM

A very good point, Mr Rustler. I have two and one was advertised as a Max III when I bought it and I never knew there was a difference. On closer inspection, they are both labelled 'MAX-S' on the transfer side. One is stamped '35' and the other I have just discovered as I type this is a '30 RC', which changes things a little bit. They are externally identical, so the option possibly remains to get a Bristunt 35-S ABC P/L set for the 30 assuming its a simple bore difference. Either way, methinks this is just the excuse I need to build BOTH a Hooptee and a Stunt Machine...

Thanks for making the distinction, Sir.

If you want to have a 35S with Brian's ABC set up, then the "30" will give you an engine that reports say is stronger than the stock 35S, and youwill still have the 35S. I would go with the "35" size over a 30 any day. The extra power is nice to have especially since you will save a tiny bit of weight and the extra fuel needed will not be much. For a Stunt Machine, you can use the extra power.

ash · « **Reply #9 on:** February 17, 2006, 09:42:11 PM »

I'm not sure I'm following you, Bill L. Do you mean to put the ABC P/L into the 30, making it a 35? And when you say "an engine that reports say is stronger than the stock 35S" I assume you mean stronger due to the ABC parts rather than stronger because of the 30 crank/case etc...

Either way, thanks for the advice, much appreciated!

I'm very keen to get these things running and see how they perform. That will be a good indicator of the path to take. I don't think I'm going to be able to resist the Stunt Machine for much longer!

Bill Little · « **Reply #10 on:** February 18, 2006, 01:04:59 PM »

Quote from: ash on February 17, 2006, 09:42:11 PM

I'm not sure I'm following you, Bill L. Do you mean to put the ABC P/L into the 30, making it a 35? And when you say "an engine that reports say is stronger than the stock 35S" I assume you mean stronger due to the ABC parts rather than stronger because of the 30 crank/case etc...

Either way, thanks for the advice, much appreciated!

I'm very keen to get these things running and see how they perform. That will be a good indicator of the path to take. I don't think I'm going to be able to resist the Stunt Machine for much longer!

Hi Ash,
Yep, Brian's 35S ABC set up in the 30 case. Should come our lighter than a stock 35S. The "power" increase might be due to the possibility that it will vibrate less puttnig more usable power to the prop, plus a tighter seal.. I would like to get one of Brian's set up, but I can't right now. Too many other projects for the "hobby dollars'! LOL!!

BUILD THAT STUNT MACHINE!!!!!!!!!!!!!!

rustler · « **Reply #11 on:** February 18, 2006, 01:53:58 PM »

I'm trying to clear out a lot of engines I will never use, but what's an engine nut to do? I couldn't resist having an example of a classic stunt engine, and have just purchased one of Bristunt's ABC set-ups for my last Max-S35. It dropped in perfectly, and if I ever have time, that Stunt Machine looks like a real contender.
The Max-III 35 is a much heavier engine, with integral steel fins, held to the c/case by only two screws, fore and aft. They are excellent powerful motors, but a bit wild for stunt. The earlier Max-I and II 35's were also good stunt motors. Agree the other comments on Max-S 30 and 35. In England I think we would say "more powerful" rather than "stronger". For our usage we could e.g. confuse stronger as meaning less liable to damage in a crash.

ash · « **Reply #12 on:** February 18, 2006, 09:42:51 PM »

Ah, now I know the one you mean, I had a Max III 20 that I tweaked for slow combat. It was very good and I passed it on to a junior flyer to learn with.

Building of the Stunt Machine is dependant on confirming some heritage details. I'll post on that matter later. Thanks again guys!

Author Topic: OS35S Max III (Read 2813 times)

ash

OS35S Max III

RandySmith

Re: OS35S Max III

ash

Re: OS35S Max III

Marvin Denny

Re: OS35S Max III

RandySmith

Re: OS35S Max III

rustler

Re: OS35S Max III

ash

Re: OS35S Max III

Bill Mitchell

Re: OS35S Max III

Bill Little

Re: OS35S Max III

ash

Re: OS35S Max III

Bill Little

Re: OS35S Max III

rustler

Re: OS35S Max III

ash

Re: OS35S Max III