Fly away rail guides

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Rocketmom

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I Got word from AMW that they have stock of all fly away rail guides. And including the long awaited 29 mm guides for a great price of $22.00! What a great stocking stuffer!!! Check it out at www.amwprox.com!!
 
So how well do these actually work for the REALLY fast movers? 54mm full L/baby M's, 75mm full M's, 98mm baby O's, etc. No issues with these rockets flying straight? Or the guides hitting the fins and breaking?

Anybody try them with equally high performance 2 stagers? Not having to secure a tower for my someday 75mm M to 54mm M would be swell but that will be one looooong rocket.
 
We've had success with some very fast motors, including minimum diameter flights with the Loki J-1000 (38mm) and Loki L-2050 (54mm). I honestly do not know what the most energetic M/N/O flight has been. I made a design change after the first few 75mm/98mm guides were made to go from a single rubber band to a dual rubber-band configuration with each band doubled over and the guides spring away more quickly. You can see on-board footage of a 75mm flight below which includes a frame-by-frame of the initial boost at the end of the video (this wasn't my flight and I can't remember what motor was used).

Charlie Ogino currently holds the Triploi I record and used fly-away rail guides instead of a tower.

For really fast movers, most fliers add a second rubber band or use thicker bands. Because of the hinged design and the non-linear opening torque that results, and also because the rail buttons spin and act a bit like roller bearings in the rail, there is very minimal rail friction added by increasing the spring tension with thicker rubber bands.

When properly used, after flexing once to get the rubber bands tensioned correctly and placing the guides all the way aft against the fins, fin strikes are minimized. They do occasionally break and so far that has been rare enough that I have been able to make those fliers happy. The guides are engineered to be strong and to separate as quickly as possible so that your rocket flies straight, true, and above all safely. I have deliberately not cranked up their impact durability through the use of resin casting or other materials, because in the event of a rare fin strike I would rather have the guides split in two than to hear about a fin breaking off and a wild rocket causing damage or injury. I am not aware of a single flight with my guides that has had an unsafe result and I am very proud of that. I am engaged in active research to increase durability, however I tread very carefully when doing so. In my testing, a rocket in a set of rail guides is generally more secure on the rail than with most common methods of rail-button mounting. Getting your rocket up straight is the top priority. If they break after that, drop me a line and I will work something out with you.

Rockdoc has flown more than 250,000 Ns with fly-aways and I think he has only broken one set which landed hard on a gravel road.

Bill Cook _/)_
Mayhem Rocketry, LLC

[video=youtube;Dtk3HvlGlgA]https://www.youtube.com/watch?v=Dtk3HvlGlgA[/video]
 
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As Rockdoc indicated, it's starting to get down to diminishing returns and I just don't know if 24mm is going to be worthwhile. I'll probably give it a shot at some point but they can't get much lighter and they can't get much shorter, and as the diameter decreases it gets harder to cram everything in there. It's also true that the cost of making 29mm guides is pretty much the same as the cost of making 38mm guides and I can't imagine 24mm guides getting any cheaper, so I don't know whether the pricing would make them impractical.

Bill Cook _/)_
Mayhem Rocketry, LLC
 
As Rockdoc indicated, it's starting to get down to diminishing returns and I just don't know if 24mm is going to be worthwhile. I'll probably give it a shot at some point but they can't get much lighter and they can't get much shorter, and as the diameter decreases it gets harder to cram everything in there. It's also true that the cost of making 29mm guides is pretty much the same as the cost of making 38mm guides and I can't imagine 24mm guides getting any cheaper, so I don't know whether the pricing would make them impractical.

Bill Cook _/)_
Mayhem Rocketry, LLC

Bill, I am experiencing the same problem with making a "mini Guillotine", as it requires a higher degree of perfection and thus more time is required to fabricate the components. This increase adds labor costs which far exceed and savings in material costs. And thank's for posting that fantastic slow motion video which clearly displays how well your invention works! I hope 2017 will allow me to build something so that I can use your innovative creation! :handshake:
 
I ordered a 29mm one yesterday for my Mongoose 29 & Go Devil 29 builds. Can't wait to try it out!
 
I Got word from AMW that they have stock of all fly away rail guides. And including the long awaited 29 mm guides for a great price of $22.00! What a great stocking stuffer!!! Check it out at www.amwprox.com!!

Been waiting forever for the 29mm... just snagged one. Looks like he's almost out...
 
Heh. When I ordered, there were 5 left. I almost ordered 3 of them so that I'd have spares...then I figured everyone here would kill me. ;)

One for me!
 
When properly used, after flexing once to get the rubber bands tensioned correctly and placing the guides all the way aft against the fins, fin strikes are minimized

Good to know. I plan on using mine sometime in the near future, and want to make sure I have all the latest tips on how to use them effectively.
 
I ordered a 29mm one yesterday for my Mongoose 29 & Go Devil 29 builds. Can't wait to try it out!

Groucho, your going to love them! ;)

In case some of you haven't seen them in action. I was honored with getting a production set made by Bill and, through my good friend and, his Chief Beta Tester- Gary Katawaba. The event was the recent Midwest Power 14 Launch in Princeton Illinois on Sunday November the 6th.

The idea was very simple: Take my good friend Sabrina Sager (A 13 year old dynamo of rocketry knowledge.) and, construct a simple all fiberglass two stage rocket (29mm throughout.) utilizing electronics only on top for head end ignition and, deployment of the streamer recovery system. Built at a pre-flight *tank weight* of 4.5 lbs (We weren't trying to set world records here.) and, show her how easy Staging can be if done with simple principles along with demonstrating the performance available from common small motors used in tandem. Launched from a simple 10/10 rail...no custom tower or special equipment besides the Flyaway Rail Guides to be used.

Mission accomplished-The look in her eyes when we recovered the Sustainer and, listened to the altitude playback was priceless...12,283'

Here is a quick You-Tube video shot of the flight by my good friend Nick Adams.

https://youtu.be/n1IzrAYfCzQ

A couple of pad photos of us ready to go also shot by Nick Adams.

View attachment 306655View attachment 306656

Very simple to use, strong construction and, little works of art...They landed only about 30' away after the launch. They helped us get the straight off the rail performance we wanted and, held up beautifully.

The only thing i would do different next time would be to locate them slightly higher above the fins since we did show small evidence of fin strikes but, the strong construction and, launch video showed that was not a major issue.

We (Sabrina and, i.) were very happy to debut this great little product and, thankful of the work done by Bill Cook and, Gary Katawaba to make sure they were there at the event for us to use...

Thank-you!
 
You can see on-board footage of a 75mm flight below which includes a frame-by-frame of the initial boost at the end of the video (this wasn't my flight and I can't remember what motor was used).

[video=youtube;Dtk3HvlGlgA]https://www.youtube.com/watch?v=Dtk3HvlGlgA[/video]


This was a 38mm research motor, about a J421. The next flight was on a 8100 Ns M2150 at Airfest. It has flown on M's before that but this was the first with the fly aways (the others were out of a tower). This was by far the straightest M flight though.
 
We've had success with some very fast motors, including minimum diameter flights with the Loki J-1000 (38mm) and Loki L-2050 (54mm). I honestly do not know what the most energetic M/N/O flight has been. I made a design change after the first few 75mm/98mm guides were made to go from a single rubber band to a dual rubber-band configuration with each band doubled over and the guides spring away more quickly. You can see on-board footage of a 75mm flight below which includes a frame-by-frame of the initial boost at the end of the video (this wasn't my flight and I can't remember what motor was used).

Here's my MD M-2245 ejecting your 75mm flyaway guides, they landed about half a football field away from the pad, no damage:

uIGe3IMl.jpg
 

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