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F21-8w

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horsefish

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Found some F21-8W Econoject motors cheap (13.99 for a 2 pack) at the local Hobby Lobby. I know these are older motors, but will they still be good? Also picked up a pack of Aerotech igniters for $3.00 and some igniter clips for $2.30. I basically bought them out of their remaining Aerotech stock. :D I think the F21-8W would be good in my wifes Mustang, but don't want to use them on it if they may be bad and possibly cato or have a bad ejection. Let me know your thoughts.

Bob
 

Ryan S.

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those motors are great and there is no reason they should be bad, I have some F21s from a while back and the ones I used were fine. AP motors will only oxidize over time making them harder to light, but this will not cause a CATO

BTW they will give the mustang an awesome ride
 

n3tjm

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The eight second delay may be a bit long for the Mustang, especially since Aerotech delays tend to burn on the long side... The F21-8W is great for rockets like the Estes Eliminator :).
 

Ryan S.

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maybe a little long but I think it would be okay

I plan to fly my eliminator on that motor....bye bye
 

firemanup

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I too think you'll be ok with the 8 sec with that bird, it will be a little long, but the 6 is a little early according to WRASP...

Either way it's a tough bird and the stock shock cord is wide enough i think you'll be ok with a little bit of a high speed deployment..

I looked over the flight logs on EMRR and found plenty of flights with this bird on F20-7's and F22-7's and they look to work fine.

The only flight with an F21-8 was mine and it worked fine being a second or so late but no damage..
 

Stones

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I've flown my 'Stang on 8's plenty of times with no ill effects. It's sturdy enough to handle some speed, if ejection is late, being a fairly light rocket.
 

Ryan S.

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True, the shockcord is wide, and the body tube is tough so this should take the shock....we wanna see some pics of the flight though
 

horsefish

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I figured the F21-8w would be OK for the Mustang since they seem to be pretty tuff and it recommends an F20-7w. If nothing else, I will fly them on some other rocket, as I can't pass up a bargain. I have a 7oz. scratch built that is just itching for a bigger motor than an Estes E9-8. It was built out of scrap parts, so no big deal if it is lost or trashed. :D

Bob
 
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