Author Topic: OS 45FSR & OS 46 SF (Read 3799 times)

Bill Barber · « **on:** February 14, 2011, 08:36:15 PM »

I was given a stunter without a motor that originally had an OS 45FSR in it . Went thru my stock of motors and nothing matched
the mounting bolts. Then a friend offerred me an OS 46FS that was set up by Tom Muggelton and it fits the plane well . What are the differences in these motors in how they run .
Bill

Balsa Butcher · « **Reply #1 on:** February 15, 2011, 06:17:21 PM »

Hi Bill, if no one else is going to take a shot at this, I will. 45 FSR - ringed, high RPM, low pitch, very powerful. Was used at top level in late 80's (?) but has fallen from popularity. A friend had one on a large profile. Found it liked an 11x4 prop and lots of RPM. I think the other engine would probably be a 46 SF, not FS. ABN, stock-hard to get to run consistent. Can be modified to work well. My guess Tom "Happy Camper" Muggleton re-timed it so I'd try it with a 12x5, kind of treat it like a ST-51 and it probably will be a good engine. I'd definitely give it a try.

Bill Barber · « **Reply #2 on:** February 15, 2011, 06:40:27 PM »

Thanks Pete for the info and yes your right the .46 is an SF not FS . I was given an "Arabesque" stunter and it's in great shape but
nothing I had would match the bolt pattern . The .46 SF fits but had to open the cowl a bit . Anyway I have been told that the Muggelton .46 SF likes to run in a fast four stroke and produces Lot's of torque . Looks to be a good combo !
Bill

RandySmith · « **Reply #3 on:** February 15, 2011, 06:55:32 PM »

Quote from: Bill Barber on February 14, 2011, 08:36:15 PM

I was given a stunter without a motor that originally had an OS 45FSR in it . Went thru my stock of motors and nothing matched
the mounting bolts. Then a friend offerred me an OS 46FS that was set up by Tom Muggelton and it fits the plane well . What are the differences in these motors in how they run .
Bill

Hi Bill

Both motors are fairly powerful ones, They will turn a 13 inch 2 blade or 12 inch 3 blade and need to be loaded, Try not to run a very small prop, They both can be made to run a very nice powerful high RPM 4/2, depends on which one you have, I have setup many many of both the engines, I try to get the people using mine to run a 4 to 5 pitch prop, Do not run high pitch props, as you will be flirting with a lot of runaway possiblity. pitch is just too much.
A 12.5 x 4.5 2 blade is a good prop for either motor, or you can go down to a 12 inch wide blade prop at 4 or so pitch.
The 12.25 x 4.5 2 blade Mgic and Bolly works well as does the 12 x 4.33 3 blade Magic.
The FSR has a lot of clone motors that have the exact mounting,Royal and The Taiwan built Magnums. The SF is a little wider and is a little heavier.
Please do NOT try to cut away the compression from the head to tame the motor, just use a larger load prop with lower pitch.

I have these all over the country running, you maybe able to see a few near you, or ask

Randy

Balsa Butcher · « **Reply #4 on:** February 15, 2011, 07:04:29 PM »

Thanks for the straight info Randy. That 11x4 prop I mentioned on the FSR may very well have been a 12x4. At any rate, I remember it running fast but delivering a good stunt run.

Paul Wood · « **Reply #5 on:** February 16, 2011, 09:39:20 AM »

Pete,

Randy is absolutely correct about the .45FSR using larger props. I'm flying a Tutor using an R/C version of the FSR. I've continually progressed to larger props and have found the Zinger Pro 12X4 to work well. I've closed the R/C carb to a launch RPM of 9800. Gives me 5.5 lap times and good tension overhead. I'm sure an even larger prop would work, but the gound clearance would be a factor.

Paul

Bill Barber · « **Reply #6 on:** February 16, 2011, 10:04:54 AM »

Sounds like I need to get some 12" props with a low pitch .
Thanks guys ,
Bill

Balsa Butcher · « **Reply #7 on:** February 16, 2011, 11:37:32 AM »

Hi Paul, never any doubt in my military mind that Randy would not be anything but absolutely correct. Glad we all were able to get some good info to Bill. Just a note: as the SF is not stock it may run a bit different than a stock 46SF but at least you have a good starting point.

Bill Barber · « **Reply #8 on:** February 20, 2011, 05:33:47 PM »

Today I was able to get a couple of flights with my Arabesque powered by
a borrowed OS .46 SF . Like I said this motor was modified by Tom Muggelton . One of
the mods he did was a button head , the changes seemed to have made the motor like to run
at a lower RPM. First flight with a Thunder Tiger 11 x 4.5 launch RPM was 9200 and the 51 ounce
Arabesque was turning roughly 5 second laps . Motor was producing lots of power and breaking into
a two stroke when the nose was lifted . Second flight turned into a run away , traced when I got
back home to an air leak in the tank . Need to do more testing but I am impressed
so far by the motor plane combo .
Bill

Balsa Butcher · « **Reply #9 on:** February 20, 2011, 06:06:38 PM »

Hi Bill, glad you were able to get a few runs on your SF. Although it is not stock, I would guess that that engine is waaay underpropped with an 11x4.5. My SF46, which isn't a Muggleton, turns that prop at 10,600 rpm and gives a useable rich 2 cycle run at that RPM. 9,200 sounds more like RPM you might get using an APC 12x5 prop. Just my hunch, which may or may not reflect reality.

Air Ministry . · « **Reply #10 on:** February 20, 2011, 06:59:15 PM »

Inddedie , young Bob hunt started the FSR trend , FSR .40 , with a 11 x 6 EW THREE BLADE to ' tame ' it .
A coustom prop. dunno about the pitch. The " E.W. " ( extra wide ) series of props appeared as if say two
inches over cut and reshaped.
Yatsenko props have ' a bit ' of blade area . too .

Hawker ' Sea fury ' used 5-blade prop to get enough BLADE AREA to absorb HORSE POWER on take-off, without
the torque reaction of the massive 4-blade, of a manadgeable degree , at least .NOTE ; it is the " Blade Area "
used to absorb "the Power ", of course their pitch is variable, set FINE for Takeoff at Max. H.P. / r.p.m.s to
drag several tonne of 'stores' of deck , without the aeroplane rolling around the propellor , ON acceleration .
Though with the Catapult its thrown clear and past the ' critical effect ' area; where the tourque reaction from
ACCELERATION would be unmanadgeable AT full Throttle . Ordinarlly on an airfield the throttle is PROGRESSIVELY
increased , and not 'at the stop' untill the aircraft is airbourne and ' clean ' (gear and flaps up).
Lancasters ( multi engine ) throttles were advanced assymetrically to hold aircraft straight .
This ' digression ' illustrates that theres one or two forces at work , relateing to model A/C .

11 x 6 E.W.s sorta work on a G-51 , TWO 11 x 5 Zingers get about the blade area of a yatsenko ,12 x 5 ?? .

Some were trying 13 in on the .40s , the Dia of a ST 60 prop , with a bit less pitch .Wide props not Tooth pick's.

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Other ' boogie ' was speed up with engine heat. Often a few ducts / tubes were fitted directed at Crankcase.

Was stated Revs would increase as temp came up on ground, A few laps after release the cooling had taken effect and rpm's dropped to that set.

Someone stated recently FP runaway is Temp related, maybe a peculiarity of Schneurles ?

Note; info garnered armchair potatoe mode, generally. I have a FSRS .40 , Feed Pipe Bore Dia was ' an issue ' with this. (was caught out with undersize thick wall 1/8 pipe,
leaning out @ 1/2 cirle hight.) Otherwise good steady speed run even in semi gale conditions, 12 x 5 min. prop was minimum to stop revs ' bounceing and holding ' .
Have the 13 x 5 Zinger I used with back of tips rounded , (full L.E. length ) .

Or in short, as Randy says ; put a bit of propellor on it , please .

Bill Barber · « **Reply #11 on:** February 20, 2011, 07:46:31 PM »

Pete since I don't own the motor yet , I went with owners recommendation on props .
Granted he tends run all his motors richer than I would . But I will likely buy the .46 SF
and then try out larger diameter props. Thanks again for the advice , will do more updates .
Bill

Balsa Butcher · « **Reply #12 on:** February 24, 2011, 09:50:27 AM »

Just checked, current prop I'm using on that engine is an APC 12x4. Turns it with ease at a pretty high RPM.

Bill Little · « **Reply #13 on:** February 24, 2011, 12:15:17 PM »

Sounds like a case for the Govt. Surplus Rev Up 12-5s that the market was flooded with a while back....... haven't found a "true" 5" pitch in the mass I have, so far, all are under 5, closer to 4 1/2 on the Prather. LOL!! (they make good T&L St G. 51 props!)

Bill Barber · « **Reply #14 on:** February 24, 2011, 04:30:15 PM »

Pete my .46 SF does not like high RPM's , tested on the ground it's turning a TT 11x4.5 at 9200 RPMs .
The original owner of the motor ran it a 4 stroke mode with an 11x4 . My guess is that Tom Muggelton
modified so it runs a very strong 4 stroke mode . Still plan to do more prop testing .
Bill

Balsa Butcher · « **Reply #15 on:** February 24, 2011, 04:57:40 PM »

Got it Bill. Mine definitely timed different. I'm sure that when you start prop testing you will find that it will pull a larger prop easily at that RPM. Keep us posted.

sleepy gomez · « **Reply #16 on:** February 24, 2011, 05:44:02 PM »

I have an OS 45 with a stamped F. The cast circle under the exhaust only has room for the 45F. Is this the same as the OS 45 FSR or other? It is a plenty strong engine.

John Leidle · « **Reply #17 on:** February 24, 2011, 10:09:20 PM »

I found the .46SF to be very powerful .I tried 4 pitch & 6 pitch on mine & have trouble maintaining consistant runs. But it is powerful ...also heavy.
John

Balsa Butcher · « **Reply #18 on:** February 25, 2011, 12:37:08 PM »

Surging in the .46SF can often be traced to the trick looking but hard to seal stock 90 degree spray bar assembly. Very prone to air leaks unless major effort is made to tighten it up. A PA or ST NVA will cure that issue. Can't do anything 'bout the weight though.

Bill Barber · « **Reply #19 on:** March 06, 2011, 04:13:28 PM »

Got a few more flights on my OS .46 SF powered stunter and this motor has definitely been retimed . Turning a Bolly 11.5 x 5 at
9000 RPM the 50 ounce plane would do lap times of 5.3 seconds . Motor would do a subtle 2/4 break when you lifted the nose .
So old Tom Muggelton really changed the run characteristics of this motor .
Bill

Author Topic: OS 45FSR & OS 46 SF (Read 3799 times)

John Leidle