HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old May 15, 2006, 09:03 PM
Registered User
stroland's Avatar
United States, OH, Wooster
Joined Feb 2005
466 Posts
Discussion
park 400 outruner powered stryker

I have a e-flite park 400 out runner that I want to put it on a stryker. Thing is a 10 4.7 prop will not fit between the rudders, so what prop? Im thinking i can incerease the pich because Im decreaseing the diamiter. But how much pich? Ive cut down a 11 7 to a 6 7 will it work? Ive ran it up and it dosnt seem to have alot of power. Im not trying to bulid a rocket, just want to get good perfromance with good run time. thanks!
stroland is offline Find More Posts by stroland
Reply With Quote
Sign up now
to remove ads between posts
Old May 16, 2006, 12:03 AM
Registered User
Livermore, CA
Joined Sep 2004
8,575 Posts
I've built a couple lite Strykers. You might try a 8060. Or, I've cut down a 9070 to fit.
It depends on the motors KV and your batt voltage. As long as you don't over amp the motor or battery, a smaller prop is fine. Butch
Butch777 is offline Find More Posts by Butch777
Reply With Quote
Old May 16, 2006, 02:28 PM
Sussex, UK
RobinBennett's Avatar
Crawley, West Sussex, UK
Joined Jun 2004
7,372 Posts
Generally, you swop an inch of diameter for an inch of pitch - but that's only a crude rule of thumb. Also you can't go past a 'square' prop (6x6 or 7x7) without losing a lot of efficency (unless it's a really fast plane, and that will still have problems launching)

Thrust is (crudely) calculated by the volume of air 'pumped' by the prop, i.e. it's swept area, pitch and rpm.

A 10" prop has a swept area of about 78 square inches
A 6" prop has a swept area of about 28 square inches - about a third.

You've increased the pitch by about 50%, which is nowhere near enough to compensate for losing that much prop area.

I'd cut the prop down as little as possible, and add the same number of inches of pitch - but it's usually worth buying a prop in each size around the calculated size and just trying them.

The easiest way to speed the motor up is higher battery voltage - if you're using a 2s battery, try a 3 or 4s.
RobinBennett is offline Find More Posts by RobinBennett
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Eflite Park 400 kepople Power Systems 14 Jan 14, 2008 10:58 PM
Eflite Park 400 Brushless Motor for Zoom? spessx Mini Helis 11 Jul 26, 2004 12:55 PM
Phoenix 25 E-Flite Park 400 in Shogun Problem dvhorn00 Mini Helis 0 Jun 30, 2004 11:17 PM
Alert Park Zone F-27 Stryker Kado Parkflyers 24 Jun 27, 2004 02:14 PM
Anybody ever use a geared Razor 300 on a 400 size powered glider? BING! Electric Sailplanes 0 Apr 16, 2004 03:32 PM