I've got a Fox Eagle that's either a .60 or a .74 (by it's size). How can I be sure which one it is? There's no marking on the case other than Fox Eagle.

the only dif is the bore the .74 has a 1.000 inch bore the .60 is .937 inch. The only way to tell tel is take the head off and measure the bore.
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Onepern, Thanks for the info. The head was removed and the 1" bore was good news, a .74. I'm going to try it out on my Seagull Harrier 3D with a 15-4 prop tomorrow.

heres a list of prop sizes that fox recommends for the .74

PROPELLERS TO USE:

We recommend that you use only hardwood propellers and stay away from the plastic ones. The reason is, that if you should be so unlucky as to put your hand in the propeller arc, the wood propeller will not hurt you so bad.

Now - about the sizes to use: An 11" Dia x 8" Pitch ranging up to a 14" Dia x 6" Pitch is the practical range. For a 5 ft. sport model we suggest an 11-8 or 11-9 prop. For a 6 or 7 foot model we suggest a 12-6 or 12-7 prop. For an 8 or 9 foot model we suggest a 13-5 or 13-6 prop. 14-4, 14-5 and 14-6 can be used also.

Where quiet operation is important, lean toward the slower running props. Rounding the blade tips also helps.

Thanks again for your prop info. I like your sig. arc&f idea. I've bought some planes "in the bones" for a song at swap meets and covered them with my idea of a wild look. One of them is a yellow flying wing Morris Spinsation with a black batman silhouette on it. Wild looking.

no prob this is my latest creation all i have left is to finish covering the top of the bottom wing and paint both wings its 1/4 EAA Bipe powerd by a fox .74

Show & tell--here's mine:

looks good

Its done

Sharp b-plane.
A northerner that builds during the summer has to have a lot of free time or all his planes have been crashed!!

LOL dropped out of the hobby for 12 years. didn't have any built planes left but I still had all my motors and radio and this kit that I never got around to building because it look like a pain to build and it was.