scott finnie Posted January 30, 2015 Share Posted January 30, 2015 Im needing a breakdown of what pitch would be best ect on a 24" prop. My original being a 24x6. I've seen a 24x12 for sale and not sure what the difference would beThanks Quote Link to comment Share on other sites More sharing options...
eflightray Posted January 30, 2015 Share Posted January 30, 2015 You wont know until you fly the plane. The 6" will give better acceleration, but lower top speed. The 12" will give lower acceleration, but a higher, (eventually) top speed. But will take/need more power. A static thrust test may give odd results as the 12" could be stalled. Quote Link to comment Share on other sites More sharing options...
ceejay Posted January 30, 2015 Share Posted January 30, 2015 theoretically its double,(as is the load on the engine) as in 12" of forward movement per revolution as opposed to 6" but the science aint that easy, so why do you need more pitch, and what engine is it on, if you need more thrust,then to keep the loading approx the same go down an inch on diameter and up to 8" pitch so a 22x8 would be a good start, depending on the engine just up to a 24 x 8 might be OK with a tweak of tuning, as would a 22x10, but even this depends on what the prop is made of, ie wood,carbon,GRP, (i assumed it was a wood one as these are the sizes used on my Zenoahs) cheers chris Edited By ceejay on 30/01/2015 20:02:28 Quote Link to comment Share on other sites More sharing options...
scott finnie Posted January 30, 2015 Author Share Posted January 30, 2015 Its a Avio Mac 75 twin. I had prop failure a few days ago and about to order a new one. Was curious to see what the main difference would be. With the setup I had its was up within 20 feet. Not fussed about higher speed as its a very old cub. As long as it flies and isn't trying to hard I'd be happy Quote Link to comment Share on other sites More sharing options...
Pete B Posted January 30, 2015 Share Posted January 30, 2015 That wooden prop was a 24x6, IIRC. I know it was a short flight but did you get the impression it was 'right'? If so, stick with that... Pete Quote Link to comment Share on other sites More sharing options...
cymaz Posted January 30, 2015 Share Posted January 30, 2015 My mind is like porridge at the moment..long week at work. This link might be of use...sorry, there's a lot of maths! Quote Link to comment Share on other sites More sharing options...
scott finnie Posted January 30, 2015 Author Share Posted January 30, 2015 Yes it felt really good. Had a lovely scale feel. Could have had a little more thrust to fight the wind though it still fought it. Anyone know if the AGM propellers on eBay are ok? Was going to buy a few to try Quote Link to comment Share on other sites More sharing options...
ceejay Posted January 30, 2015 Share Posted January 30, 2015 using Zenoah's 74/80 twins as a guide i would have thought a 24x10, (got this size on my 80,s in a 1/4 scale zero and a 1/3 scale Piper Pacer glider tug,) or a 26x8 would be the one's, (club mate had this size on an 80 in a 1/3 scale Pup,) personnel preference for a nice scale cub like flight would be the 26x8, chris Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.