Fox 25 and Ringmaster Jr. .19

This is the first kit model I've built in 30 years. I was going to put a Veco 19 in it but it seemed too large and heavy. I dug around in my old engine box and came up with a vintage fox 25. I'm not sure of the age of the engine but I think it may be a 1954 "25" (.257) and is basically a bored out "19". Can someone look at the pics and see if I guessed right? The engine has great compression and is very light for the displacement. Any suggestions for what prop to use on this engine? I've selected a 3-ounce tank, too big? How long of a run with this tank?
http://groups.msn.com/NorfolkAeromodelers/shoebox.msnw

The kit is a fairly new Sterling/Estes. In my opinion it has several shortcomings. No covering supplied with kit. The plastic wingtips suck. I made my own wingtips from balsa. I dislike having to build a wing from a 1/2" square stick for a leading edge. I think the original Ringmasters had a formed leading edge. On a positive note all the balsa was of a good grade and the die cut pieces separated easily.

I have two of these engines and you are right. The early Fox .25 was a bored out .19. They are extremely powerful engines and I think you will find it to be too much engine for the plane you have built. This engine will fly a full sized Ringmaster or Flite Streak with ease. I have flown the oldest one I have on a Yak-9 and it did a very good job of powering the plane. When one of my flying buddies saw my old Fox .25, he commented that those engines are almost as powerful as a Fox .35 and he was right. You have a great engine there....you just need a larger plane to go with it................TD

I have an .09 on my Ringmaster Jr.
But in all fairness, the Estes box shows a Schnuerle .25 and the instructions mention testing with a .25. Must have been for some type of racing use. Highly NOT recommended combo.

Your engine came in three varieties, .19, .201 and .25. All have the same case. The .201, the rarest, was used so competitors could use the same airplane (Free Flight, usually) in both the old A and B classifications. They were introduced in the 50s.

Agree that this is much to much engine for a Ring Jr, even though it is light for a .25. The best Fox matchup is the .15 baffle. Modern Schneurle .09s and .10s are good, too.

George: I think the Estes R. Jr has a little bigger span, like 3" bigger than the original Sterling R. Jr.

But, still, way too much motor, agreed. Currell

Tom: You are correct in that the original R. (Kit S-1) had a solid LE. The next design iteration, the S-1A, which came out around the late '70s, has a D tube wing, and is lighter.

>George: I think the Estes R. Jr has a little bigger span, like 3" bigger than the original Sterling R. Jr.
>But, still, way too much motor, agreed. Currell

Currell,
I think the top view of the Estes plans has a separation (probably the three inches) so that you can build separate wings, then connect them. If I build another, I think I'll include the separation as part of the wing and stick a baffle .15 on it (as you suggested).

>The kit is a fairly new Sterling/Estes. In my opinion it
>has several shortcomings. No covering supplied with kit.
>The plastic wingtips suck. I made my own wingtips from
>balsa. I dislike having to build a wing from a 1/2" square
>stick for a leading edge. I think the original Ringmasters
>had a formed leading edge. On a positive note all the balsa
>was of a good grade and the die cut pieces separated easily.

Tom;

This engine will swing a 9-6 nicely using an all castor lube based fuel. Years ago I flew one of these on a number of S-1 Ringmasters (the full size version), and it flew very nicely.

If memory serves, Don Still used this engine in one of his Stuka variations back in the mid - late 1950s, and had good success with it.

I think it will be too much engine for a Ring Junior. If you can scrounge up a full size Ringmaster kit, or scratch build one, you will find it handles 400 sqi ships just fine.

Ditto on the plastic tips. Same thing on the full size R, too.

It is a snap to replace them with the usual balsa, though.

I've got an Estes Ring Jr kit and will be putting an early Fox 15 baffle on it. I had this engine on an original Ring Jr with 52'x .015 lines and remember slack lines in the overheads. I think the Estes kit is lighter.

I have two built Estes Ringmaster Jr's one with a Fuji .15 and the other with a OS Max .19. My 8 yr old son Aaron flies the with the Fuji and I fly with the OS .19... BIG difference! That little .19 rips thru the circle like a combat plane, something to get your reflexes hopping! The Fuji has a nice 4-2 but my son is still just going in circles. Both of these planes have been slammed in the ground (grass) more times than I can count, epoxied, cya'd, re-monokoted and slammed again!! I can't imagine one with a .25 of ANY make! I am going to replace the .19 with a MAX-III .15 before I fly it again... I run the .19 with a 8/5 or 8/6 and the Fuji with a 8/4

Bill,
You can use 52'x.012's with the .15. I think you'll find a BIG difference.
George