Prop suggestion

[Gary Dowler]

Flying weather is coming. Though with our brand new frigid temps and 5" of snow it may be further off that it looked a few days ago.
I have a new to me Ringmaster that wears a Fox 25. Both are new to me. Never got a flight up on it last season. I'm inclined to prop it with a APC 9-4 as I do my 20FP's. I don't know enough about the 25 to really know if this is right.  It seems a better revving motor than the old 35.

Suggestions?

Gary

[peabody]

Foxes don't like revs like an FP
Try a 10 X 6
Make sure that you have plenty of high castor (25%+)
The APC 10 X 6 will be fine to start with..

[Fred Quedenfeld jr]

which fox 25 is it the old one that is similar to the fox 35 stunt or the newer schnulee ABC
the old one runs slow with more pitch  the new one less pitch with lots of rpms
Just My 2 cents
Fred Quedenfeld

[Peter in Fairfax, VA]

Yes, which Fox .25?  There are several distinct ones over the years. Send a picture, if needed.

Peter

[Gary Dowler]

which fox 25 is it the old one that is similar to the fox 35 stunt or the newer schnulee ABC
the old one runs slow with more pitch  the new one less pitch with lots of rpms
Just My 2 cents
Fred Quedenfeld

I'll look when I get home from work in about 2 hrs.

[Gary Dowler]

One Large port behind the baffle piston.

[Brett Buck]

One Large port behind the baffle piston.

   9-6 or 9-5.

    Why is it taken apart?

    Brett

[john e. holliday]

I use 9-5's on my Fox .25's.

[Gary Dowler]

   9-6 or 9-5.

    Why is it taken apart?

    Brett

Just to get a good look at the ports. With the height of the baffle on the piston I couldn't be certain of just what was hiding in there.

Gary

[Air Ministry .]

I run TF 8x6 , 9x6 , or 9x4 ( best ) on mine. In twins .

If its light & you want the 5.0 per lap bit , the topflite nylon 9 x 4 orIve used Zinger 9x5 woods .

This test ( sceptre flight ) is the later retimed one - Black steel prop driver .They wake up on 15 or 20 % nitro . & can run ' the break ' .



Think I run the heads around 7 thou. clearance . They varied a bit .

Yours is a earlyish , 1972 maybe , as only vertical weeny muffler screw thingos .74 ish on there fore n aft also . later undrilled on the up & down .

[Air Ministry .]