Quantcast

Roadrunner Motors

The Rocketry Forum

Help Support The Rocketry Forum:

Marlin523

Well-Known Member
Joined
Jul 26, 2009
Messages
721
Reaction score
0
When designing a rocket are there any special things to consider the use of these motors compatible with other motors? What length should the motor tube be. The site says no hooks. What retention system do you use? Thanks for your info
 

troj

Wielder Of the Skillet Of Harsh Discipline, Potent
Joined
Jan 19, 2009
Messages
13,962
Reaction score
187
The problem with engine hooks with APCP motors is that the ejection charges are typically more energetic than BP motors, so the motors will often pop past the hook.

A better route is to use a screen clip, or something similar.

-Kevin
 

n5wd

Well-Known Member
Joined
Jan 18, 2009
Messages
1,030
Reaction score
2
When designing a rocket are there any special things to consider the use of these motors compatible with other motors? What length should the motor tube be. The site says no hooks. What retention system do you use? Thanks for your info
Marlin,

The Roadrunner motors have a built-in thrust ring that'll keep the motors from continuing down the motor tube. You'll need some sort of motor retention, or do like many people do and use masking tape to friction fit the motor into the tube. I usually try to keep my motor tubes long with a centering ring on the top to minimize the ejection charge gas just filling up dead space.

I use "Kaplow clips" on my 29mm rockets for retention - brass strips that engage the thrust ring, and are secured by T-nuts and bolts on the aft centering ring.

You'll enjoy using the Roadrunner motors - it's about all our TARC team uses any more.
 
Last edited:

New Ocean

Well-Known Member
Joined
Nov 19, 2009
Messages
855
Reaction score
0
Or electrical tape. It has never failed me at about 10 cents per flight. It actually locks in tighter during the burn as it melts a bit.
 

shreadvector

Well-Known Member
Joined
Jan 19, 2009
Messages
9,008
Reaction score
191
Sounds like trying to find/buy Roadrunner rocket motors here in California. :(
Maybe it's the Warner Bros attorneys?

I've actually seen 1 roadrunner in my 29 years in CA, and it was running down the road in my neighborhood a couple of years ago. I asked a bird expert who said they are somewhat common in this area, but that is the one and only one I've ever seen. They must get squished a lot.
 

H_Rocket

Death by Powerpoint
Joined
Jan 18, 2009
Messages
3,818
Reaction score
225
Location
North Central Texas
Something about a 5.5" CF airframe with a 440 cu in Magnum with a six pack induction system sounds just really "knobby"








Actually that would not really work as my 426 Hemi required anything but knobs. in fact I used slicks.
 

rocket999

Well-Known Member
Joined
Jun 27, 2009
Messages
75
Reaction score
0
Our club uses lots of Road Runner motors. I use tape to hold them in. Pretty much as cheap and simple as it gets. Works fine.

Sam
 

kelltym88

Well-Known Member
Joined
Jan 18, 2009
Messages
3,865
Reaction score
6
Maybe it's the Warner Bros attorneys?

I've actually seen 1 roadrunner in my 29 years in CA, and it was running down the road in my neighborhood a couple of years ago. I asked a bird expert who said they are somewhat common in this area, but that is the one and only one I've ever seen. They must get squished a lot.
You didn't see it because it was probably strapped to an ACME rocket chasing a coyote! :roll:

But seriously, are Roadrunner motors not CSFM aprroved?
 

Latest posts

Top