Opinions on RoadRunner SU Motors?

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Pem Tech

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Right up front I want to say I like RoadRunner's 29mm SU motors.
https://www.roadrunnerrocketry.com
There is a good variety of impulses, they light the first time every time (in my limited experience), their delays are accurate, I have experienced no CATOs, they come with a real two lead igniter, I almost always support the smaller manufacturers (Keeps the big boys honest) and Bob is a grand guy. We have exchanged a few emails and he seems quite nice. As a matter of fact, a couple of years back he sent us batch of free motors including F35's, F60's and G80's. You can't get much better than free motors!

So, my question is, what is your opinion of RoadRunner motors?

This is why I ask...
Last year at Southern Thunder I launched my King Kraken on an F60. In comparison to other motors in that class and propellant type the RR's just didn't seem to catch the attention of the onlookers. I thought it was great cause' I got her back in one piece. (Any launch you get your rocket back in one piece is a good launch) But even Trudy mentioned that the launch wasn't as dramatic as other F & G motors. I am guessing she means smoke, noise and flame.


As a comparison, here is my King Kraken lifting off on a Road Runner G80-4 at Saturday's MSRS launch in Memphis TN.
kk_1550.jpg


The youngsters loved it! Most had never seen any motor over a C and were awestruck by the spectacle.
The KK's second flight that day was on a G64-4

kk_1581.jpg


The kids and a few adults were much more enthusiastic about the G64.
Now I know the G64 is Whitelightening propellant and puts off a lot of smoke, but the motor has a deeper, more throaty roar that, in combination with the thick white smoke, seems to command more attention.

Am I imagining this?
:confused:
 
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The G64 launch photo looks interesting... All of the G64's I've seen have had a well-defined flame and very white smoke. In this case the flame is partially obscured by smoke and the exhaust plume itself seems much darker than normal. It's almost like it had 1 G64W grain and 1 G53FJ. They are bifurcated, right?
 
I've only flown one, a G80-10RR.

I thought it was a pretty neat motor but I also thought it was relatively quiet for its size compared to something like an AT G64W which is probably one of the loudest MPR motors available.

But it was given to me by a club member so I'm certainly not going to complain about a free motor.;)
 
Interesting; the second photo shows the leads still attached to the rocket....

That said, I've never really paid much attention, but you're right, when I think about it, the Road Runner motors are more quiet.

For me, and others in the area, though, that's never been an issue. I sell Road Runner motors, and it's never been an issue. I actually need to get more in, as I run out of G80s fairly quickly.

-Kevin
 
A loud roar and lots of smoke are definitely pluses to me, but I would not be at all disappointed with a brand of motors that doesn't deliver them. I would be more let down if I fired a motor, such as an Aerotech with WL, that for some reason didn't produce the expected effects. The effects are great and I expect to see them in motors that advertise them, but in general, I select motors that will make my rockets go regardless of whether or not there is a marching band to send them off. After all, it's really all about the thrust, isn't it? Don't get me wrong; I love the fanfare. It's not the most critical factor in my choice of motors, though. With that being said, I need to add at this point that I have never used a Roadrunner motor. (Our launches are way too small to attract an on-site vendor.) And also, maybe I'm not jaded (or hard of hearing) enough yet, but to me, all composite motors sound loud.

Mark K.
 
You do realize on the engine recomendation charts on Tim's kit pages, everything that can use a roadrunner motor it says in the comment colum it says "quiet motor" I have never seen a RR motor fire in real life but just from the picture that the excitment wouldve been less on the RR motor, but there is one thing that should be noted, RR motors are competition motors, the F60 and the G80 motors are compleatly reseved for the TRAC teams, before you guys say anything, please excuse the poor spelling :D
 
The G64 launch photo looks interesting... All of the G64's I've seen have had a well-defined flame and very white smoke.

Normally that is the case but maybe this was an older G64. With old AT White Lighting motors, the flame tends to flicker and they crackle quite a bit too.

At the last launch I flew an H123W in my King Kraken dating back to 2006 that displayed a similar effect although the flame was somewhat brighter and more visible and the smoke was not as dark as in the pic of Layne's G64.
 
As a plus for "quiet motors", our largest field is abutted by an apartment building (full of cool people) and some single family homes (partly populated by un-cool people). We've had to appear before the local Parks/Rec committee to address complaints over the years. Noise has been part of many of these issues; the Road Runner motors may not scream for attention like some others but they always provide a great flight.

If it helps us keep access to this field, I'm all for it.

Meanwhile, who's got the formula for Hushaboom. If we're going to be quiet, we may as well have some fun, too.
 
The roadrunner motors are excellent in reliability, they do their job, and they light quickly. They are quieter and don't have as much flame or smoke though, so they don't quite have the "crowd pleasing" factor quite as much. They are excellent motors, but it's true that if your goal is flame, smoke, or noise, they probably aren't the best choice.

Oh, and I agree that G64 photo looks kind of odd. I'm more used to seeing G64s look like this:

https://www.nescornarocketworks.com/Images/SaturnV/IgorTryndin_IMG_5456-cropped.jpg
 
RR motors are reliable and affordable. I love them.
 
... but there is one thing that should be noted, RR motors are competition motors, the F60 and the G80 motors are compleatly reseved for the TRAC teams, before you guys say anything, please excuse the poor spelling :D

Huh? I think you'd better go back and read that web page again, young 'un. Bob sells the E25's and F45's to anyone, shipping them via the US Postal Service, to anyone in the US. But because of the FEDEX HAZMAT paperwork and fees that have to be charged for the F60's, he only goes through that hassle for TARC teams because he wants to help the kids out when they likely couldn't get the motors any other way. The G-80's aren't legal for this year's TARC contest, by the way, so that's a moot point.

Over the years, I've probably flown, or witnessed being flown, several hundred Roadrunners (Bob's a local and DARS member - and we've used the Roadrunners exclusively for the previous two years of TARC). Out of all those, only 2 CATOs (both of 'em on TARC teams I sponsored last year) - pretty reliable. And, while they might not be the loudest motors on the block, they don't suffer from bonus delays, or short delays, and they light the first time - not sitting there on the pad chuffing for a few seconds. I'll take that over 'exciting' any day of the week!
 
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The G64 launch photo looks interesting... All of the G64's I've seen have had a well-defined flame and very white smoke. In this case the flame is partially obscured by smoke and the exhaust plume itself seems much darker than normal. It's almost like it had 1 G64W grain and 1 G53FJ. They are bifurcated, right?

Yes they were...
But one grain was loose and showed oxidation while the other was in a sealed pouch and was quite clean.
 
Interesting; the second photo shows the leads still attached to the rocket....
-Kevin

Yes, that was an interesting phenomena.....
The clips were standard LPR micro clips, so I am really surprised how well they held on. The second bit was that when the igniter wire was recovered one of the leads had been completely ripped from the second, for the full length of the igniter, and stripped the insulation from one of the separated halves.
Lost both of my igniter wires that day.
:(
 
I have used several of them. Mostly in a three X 29mm clustered rocket. They seem fine to me. I've never had a problem.

Plus .... Bob's a great guy.
 
I think they are great. If you are about propulsion and an economical flight they are fantastic. Very reminiscent of Thor's Hammer (Ellis Mountain). If you are looking for polka dot sparky motors with a whistle effect, then they are probably not for you.
 
I think they are great. If you are about propulsion and an economical flight they are fantastic. Very reminiscent of Thor's Hammer (Ellis Mountain). If you are looking for polka dot sparky motors with a whistle effect, then they are probably not for you.

Best post ever! (Well, at least in this thread.) ;)
 
Yes, that was an interesting phenomena.....
The clips were standard LPR micro clips, so I am really surprised how well they held on. The second bit was that when the igniter wire was recovered one of the leads had been completely ripped from the second, for the full length of the igniter, and stripped the insulation from one of the separated halves.
Lost both of my igniter wires that day.
:(


I wrap the leads around the leg of the launcher thus insureing they pull out, the only time you don't wrap the leads is on a cluster, just in case 1 or more of the motors haven't lit yet. Sometimes a little extra time is all that's needed.
 
The G64 launch photo looks interesting... All of the G64's I've seen have had a well-defined flame and very white smoke. In this case the flame is partially obscured by smoke and the exhaust plume itself seems much darker than normal. It's almost like it had 1 G64W grain and 1 G53FJ. They are bifurcated, right?

That picture of the G64 was taken where it was really humid. The WL motors look different depending on how humid it is when launching (bright flame, white smoke when it is dry out; like the picture when it is humid). Something with the way the Mg burns depending on humidity.
Daniel
 
Interesting; the second photo shows the leads still attached to the rocket....

-Kevin

I've had a couple of instances where the red cap holding the copperhead in place never came off the motor. Maybe I cut too big of notch in the end. I got the rocket back with the end of the copperhead still sticking out the top of the red cap and the bottom end of the red cap burned away.

Maybe that is what happened here. The burning cap is affecting the flame/smoke from the motor and the end of the copperhead is still extending from the top of the red cap and pulling the igniter wires up.
 
I have always been happy with these motors! Good stuff!:clap:

Mike

Tripoli# 5199
 
I too have had good experience with RR motors..Though it has been a while since I launched one..In fact it has been a while since I have launched anything...:rolleyes:
 
They are good motors. I've flown a few, and like everyone has been saying they are nice, but don't have a big flame (if they have one at all). They are also pretty quiet motors.

I would recommend them.

Sam
 
I've had a couple of instances where the red cap holding the copperhead in place never came off the motor.
Start of off topic note...

I saw a tip on the Apogee site which shows cutting a slit along one side of the red cap. The cap then will still fit over the nozzle tight enough to hold the copperhead but will easily come off when the motor ignites.

End off topic note...

Back to your regularly scheduled topic
 
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Start of off topic note...

I saw a tip on the Apogee site which shows cutting a slit along one side of the red cap. The cap then will still fit over the nozzle tight enough to hold the copperhead but will easily come off when the motor ignites.

End off topic note...

Back to your regularly scheduled topic

The end cut/slit in the caplug is to allow the pressure from the burning pyrogen of the igniter to vent without building up and "popping" the igniter out of the motor and snuffing out the ignition process.

The cut/slit does not allow the plug to come off easily. it actually provides a releif vent so that the motor must build up a lot of pressure to blow off the plug. If you have crammed the plug on tight and the iginter is wedges between the plug and the nozzle tight, then the plug may stay attached with a dangling remnant of the igniter. This happens when the motor simply melts/blows a hole in the center of the caplug, yet the outer lip remains tightly attached to the outside of the nozzle.

You can develop a "feel" for the proper tightness and simply not cram the caplug on 'all the way' or even cut a slit in the edge to allow it to fall off easier - which is what Apogee is telling you about. I'll see if I can find the link. (Nope, can't find the link. If you can, post it.) The trick is to not allow it to fall off TOO easy or the igniter will spit out before the motor comes up to stable ignition pressure.
 
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Flew my first Roadruner in Brothers, OR over the weekend. Very cool!

I used an F60-4 in my heavy duty Big Daddy, and it was a great flight. Delay seemed to be dead on, and ignition was very quick. Not a huge amount of smoke, but it was dark! The motor was a demo courtesy of our local vendor, Sun River Nature Center.

Almost lost it in the sagebrush, but a fellow rocketeer happened upon it. :)
 
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