Introduction and Engines query

[Simon Lumsdon 1]

Hello

Firstly wanted to say hello and thank you for having me on the forum. I am returning to the hobby after a 20 year lay off (kids) being encouraged by lock down to start building again. I have built planes from being a kid in Scotland over 40 years ago so its definitely in the blood. I have just joined a local club and busy building some planes to help me get up to speed again. I seem to have collected a lot of engines so lots of opportunities to keep me busy

Engines

Cox 049 -sentimental value

1cc Diesel (old) - in an unfinished Vic Smeed Tomboy

1.3cc Mills - planning for a Just Junior

PAW 19 RC - planning for a Junior 60 (again)

OS 20 FP Courgar?

OS 40 FS Surpass Super60?

OS 52 FS Surpass

I do have a small 3 channel retro electric from an Avicraft kit that i have been cutting my teeth on but looking forward to something bigger. Currently building a Super 60 4 channel and a Cougar 2000 fun fly, again intended to be used initially as a 4 channel trainer.

Now onto my engine questions, I was hoping to bolt the 52 onto the Cougar but it looks massive and frankly far too big, question, will the OS20FP be OK for use as a trainer, I think they recommend 25 as a minimum but was hoping I could use the 20 to begin with and move up from there? The alternative is to use the OS FS 40 but again its still looks too big? I dont need the thing to prop hang or climb vertically, just enough for me to get my confidence back after a long time out.

On the Super 60, has anyone any experiences of using an OS FS 40 in this model? Had initially thought if using the FP 20 but this looks a bit small in what looks likely to be a largish/heavy model?

Thanks for reading and look forward to hearing your advice

Simon

[Frank Skilbeck]

I had a Super Sixty 30 years ago with the Mk1 OS40 fourstroke, was a perfect match. I also flew it on a 25 Irvine two stroke and it was OK on that too, but the OS40 fourstroke is a much better match I think.

[Peter Miller]

My recent Super 60 with OS 40 Surpass.

Perfect!!

[Former Member]

[This posting has been removed]

[Simon Lumsdon 1]

Im now thinking of putting the os fs 40 onto the Cougar (it fits the mount) and use the os 52 fs in the Super 60 on the basis that it seems equivalent to a 40 2 stroke (.9 bhp) and whilst is probably overkill, not madly so, we shall see

[Simon Lumsdon 1]

Peter, nice model, looks like you have gone for separate servos in the wings, is that a useful mod?

[Nigel R]

Hi Simon

My 2p

I would keep the 40 FS for the super 60.

The cougar, if you're using it for a low wing trainer type model, I would try to pick up a plain bearing 40FP. They're usually cheap and easy to find on the popular auction site. £30 easily gets a nice one.

Don't look at manufacturer bhp figures. They are often creative and unrepresentative of how we run our motors.

[Peter Miller]

Posted by Simon Lumsdon 1 on 13/08/2020 18:50:49:

Peter, nice model, looks like you have gone for separate servos in the wings, is that a useful mod?

Do you know I can't remember but I probably did. I do use that system most of the time these days.

IT can save a lot of fiddling with bellcranks and push rods etc and micro servos (9 gram metal geared) are excellent.

Metal gears are vital.A knock in tansit will strip a plastic gear and ruin your days flying...Don't ask how I know. But that was many years ago

[David Davis]

I flew a Super 60 with a Magnum 52 FS in it. It was a bit overpowered but not massively so but a 40FS would have been a better match.

Incidentally, mine was a Penn Models Super 60. Penn Models produced the Super 60 as a four channel ARTF long before ARTFs became commonplace. I believe I'm right in saying that they were all finished in Cub Yellow and Red Solartex.

 

Edited By David Davis on 14/08/2020 10:05:46

[J D 8]

I second Nigel R on finding a 40FP for the Cougar. I recommend them as a second aircraft for those wanting to move on from their trainer. Irvine 40 another option , always some on the flebay.

[Simon Lumsdon 1]

Thanks all for the replies and the suggestion to source an OS40FP does make sense although I think I want to avoid any more ebay action otherwise my engine collection will be out of control. I have decided to compromise and use the OS40FS in the Cougar for the mean time and the 52 in the 60. If the 52 is too overpowered I can always replace with the 40 easily enough.

David, your ARTF 60 looks great, red and yellow always works. Are those ailerons hinged on the upper edge? My Ben Buckle kit shows central hinges but I was thinking an upper edge film hinge would look better. Does it have dual aileron servos in the wings

[David Davis]

Yes Simon, the Penn Models ailerons were inset, so -called "Barn Door" ailerons. I believe that the Ben Buckle ailerons are full length along the wing trailing edge.

[Nigel R]

Yes, old Irvine 40s are easy to come by.

Whilst I like them, they do have a couple of caveats, that rear bearing is now a weird size and "a bit" pricey to get a new one, the plastic carbs are best avoided although of course many have the nice metal jetstream, and the silencer is an old single chamber and will probably need an add on behind it.

The red headed Q40 are a good bet if you can find one, good silencer, metal carb, nice motor.

[Graham Davies 3]

My old OS40FP was the first R/C motor I bought. It has powered all manner of models including a Telemaster 66, An Inwoods Improver, A Flair Baronette and various excellence/ Gangster hybrids. I love it. It is powerful enough, light enough to use as a hot option instead of ball-raced 25s, and throttle superbly. I still have it, and this thread has started me thinking about what I can build for the venerable old girl!

[Nigel R]

I have two of them in the twin in my avatar; I like them.

As you say, they are as light as a ball raced 25, but make their power at a flying-site friendly 10k or 11k rpm.

edit: not entirely unrelated, an OS 40 Surpass has approximately the same power (smidge less) and weight (smidge more) as an OS 40 FP.

Edited By Nigel R on 14/08/2020 12:19:12

[Simon Lumsdon 1]

Thanks Nigel, i didnt realise the 40fs was so powerful, i was working on

os 40fs surpass 0.6bhp

os 52fs surpass 0.9bhp

os 40 fp 1.0bhp

os 20 fo 0.5bhp

must admit to being fond of OS four strokes, nice and quiet

i

[Peter Miller]

I use an OS 52 FS in my Little Miss Honky Tonk.

THis is roughly the size of a Super 60 and is very aerobatic but not wild or hairy at all.

[ken anderson.]

welcome from me Simon...

 

ken anderson...ne..1...... welcome dept.

Edited By ken anderson. on 14/08/2020 16:09:39

[Nigel R]

Yes, 40fp will never see 1hp in our environment, not in a million years. Maybe if you run it on 80% nitro and weren't fussy about it being in one piece afterwards.

It turns an 11x6 about 400rpm more than the 40fs.

[Simon Lumsdon 1]

So I have now run in the OS40FS on the bench with a couple of tanks running rich, what a lovely engine, I had forgotten how nice these 4 strokes are. Now bolted into the Cougar and my old Futaba tranny carefully programmed with rates to wind down all the control throws. The C of G was spot on which was one advantage of bolting a big 4 stroke onto it.

Looking forward to flying it now and seeing if I have still got it

[Nigel R]

great stuff

flying's like falling off a bicycle, it'll come right back

[Simon Lumsdon 1]

Well i built the Cougar and fitted the OS FS 40 and flew it and it was a bit of a handful for a beginner i must admit, had to throttle it right back, it flew ok but felt over powered and a bit twitchy. I managed to get disorientated and binned it which broke back of fuselage at the weekend, decided to fit a good OS FP 40 i had sources on ebay following a previous recommendation, flew it this evening and much much better, smoother and steadier. The FP on a 10x6 is definitely lower powered than a FS 40 Surpass on 11x6.

Anyway, quite pleased that i now have a plane which i can hopefully get some time on to improve.

Bit disappointed in the build quality of the Cougar, extremely lightly built, just bought a Wot4 artf as its potential replacement and it much more strongly built, we shall see ...

[perttime]

"1.3cc Mills - planning for a Just Junior "

Give Control Line a try?

People have been flying Weatherman vintage speed, and I believe there is a separate class for the Mills.

[Chris Walby]

Simon, sorry to hear about your disappointment with the Cougar, but it is what it is...a light weight very aerobatic model.

I have used one for instructing new trainees and orientation can be an issue (until a couple of large Solartrim circles were stuck to the upper surface of the wing). My students got on well with it, as it could fly very slowly and on low rates is very stable, but on high rates for the instructor makes it very responsive to avoid the ground.

Mine and another one at the club have done sterling work and taken a lot of knocks and I can only think you have high rates and an incorrect C of G to make it fly so poorly.

If I could find a 4 stroke to do it justice I would get another, but may just end up with an electric version to really explore the manic capabilities.

PS - Fly the WOT-4 and get the thumbs well dialled in....then its Cougar time

[Nigel R]

Cougar is meant to be very light. And very responsive. This is it's natural environment:

If you find it twitchy, it needs the movements reducing. These sorts of models are pussycats at slow speed with reduced throws.

BTW the OS 40 FP is definitely (slightly) more powerful than a 40 FS; if yours is not then something is amiss.

Edited By Nigel R on 16/09/2020 08:42:57