Practice model

[Mark Godfrey]

I have an old Gieske Nobler that I have resurrected. Without the motor it weighs 35 ounces ready to fly.
If I powered this with an OS 25FX and flew it on 52ft lines do you guys think it would be OK?

I just figure its to good a model to let go to waste.

Mark

[Akihiro Danjo]

Without the motor it weighs 35 ounces ready to fly.

WITHOUT motor, ready to fly??

[Tim Wescott]

If I have my engines right, the FX series engines are high-power, high-RPM screamers (the 25 FX is rated at .84 BHP at 180000 RPM, vs. the 25 LA's 0.6 BHP at 15000 RPM).

It may work, but not with the same setup that a 25 LA would.  You'd certainly not be on the well-traveled 25 LA or 46 LA roads.

Someone who's actually touched, or maybe even run, a 25 FX should probably weigh in here.

[Steve Thomas]

I've got one, but use it for Plank Racing (a time-trial combination of stunt and speed  ) rather than in a stunt model. As Tim says, it's a high-rpm screamer - quite powerful but not especially light, and a popular choice in Classic B team race out here.  By the time you put a muffler, prop and spinner on it, that Nobler will be getting on for 45oz, so Bob's suggestion of an SS30 would be better (and the mount pattern is the same). That said, for just having a bit of fun, the 25FX should be fine. Maybe 60'x.015 lines, and a 10x3 or 10x4.

Steve

[John Fitzgerald]

The FX series are ball bearing engines rated for high rpm, and are considerably heavier than the FP or LA series.   You can slow the plane down with a 10/3 or 11/3 if you can find one.  They don't run well in a 4 stroke needle setting.

[bob whitney]

as everyone has said ,the FX25 is a very well made engine but  dose not like to run slow  ended up putting mine on a profile and letting it scream on a 9/6 and have fun with it

[Ted Fancher]

FWIW, back in the WAM contest days we used to fly engine classes of stunt: 1/2A, A and BC w/Beginner, Intermediate, Advanced at Expert classes at major meets.  Once we got turned onto the little Veco 19BB we flew some fine stunt with Dolphins, Banshees and, yes, Gieseke Noblers spinning low pitch props at high revs long before the "enlightenment" of the pipe era.  I'd be a little skeptical of a regular Nobler with the big flaps but I could even be proven wrong there.  The little Veco was extremely strong.  Brett might have a good enough memory to rank it with the various traditional OS variants (the FPs and the LAs) but my recollection would be that if anything, the Veco might have been a smidgen more powerful.  It was ball bearing equipped but was no remotely heavy for its displacement.  It would be a dandy choice if one found one on Ebay or a garage sale.  It originally came with a very light expansion chamber muffler that worked effectively and which we used on all of our applications.

Ted

[Mark Godfrey]

So the reason for this was because I had fitted in the Nobler originally a GloChief 29. Sadly it was lacking in power and wasn't very reliable so I had a look in my engine collection and the closest size wise motor I had was OS 25 FX. Yes Steve Thomas I have two of them and they are both out of my Classic B team racers.
In the TR models they run 7x7 APC props and they do it good.
I figured with a tongue muffler (little weight) and a 9x4 or 10x4 prop I might be able to get it to run slow enough.
Fast Forward to last night.
Whilst looking at engine crankcases I put my GloChief 29 on the table alongside my OS 46 LA and Guess What 
they have the same bolt pattern, so now I can run my 46 in the Nobler and that should work fine.
Thanks for advice people sorry it was for no real purpose but I would never had thought that my 29 made in 1958 and 46 made in 2012 would swap holes.
So now I have a practice model.
  Hi Steve.

Mark

[Tim Wescott]

The 46 LA ought to do well.  Check for balance: if the 46 is heavier you may need to put in tail weight.  Fortunately a Nobler is at the low end of what that motor can pull, so if it's a bit overweight you won't run out of power.

Or, you can be a pioneer and use the 25 FX!

[Dennis Moritz]

I'd use an FP40 or a Tower 40 and fly on 62 foot lines or so. But folks find those engines difficult to tune.  I get them to work. Perfect size for those engines. An LA46 is more forgiving. Stock LA46 with the stock needle valve and venturi can burn as much as 6 ounces of fuel during the pattern. That is with a very rich run. Which would probably pull your plane around. Some folks favor this rich run. If you have difficulty putting a 5 ounce or more tank in your plane, you might need to go to a smaller venturi. Available from Jim Lee or OS. An LA25 would be marginal in a plane of this size and weight. A Fox35 on the other hand. Running pretty hard. Could pull that Nobler. But that is another debate that fatigues all who engage.