solid & RMS ?

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TwoWalks

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been reading as much as I can the past couple of weeks on Rockets and rocket motors. I see the belief that reloading is less expensive than solid motors. My mind also keeps saying that if you lose the rocket, you lose the motor and if the motor is a RMS then the expense shoots up (no pun intended) rather quickly. When is the chance of rocket loss lowered to make the expense difference something worth chancing? Other than cost, what other advantages are there to using a RMS in a rocket?
 
I believe there is more of a motor selection...

Any of you who know more about it than I do feel free to correct me.
 
Blue_Ninja_150 is correct that there are a lot more motor choices when you get into reloadables, and this is one of the big reasons for utlizing them.

However, TwoWalks, you are correct as well - if you are using an RMS system for a flight, and the rocket goes bye-bye, whether it gets hung up so high in a tree that you can't get it, simply drifts away, or happens to land in the exact middle of a pond that happens to be inhabited by alligators (sorry, eugenefl...), then you have lost a considerable investment. You are also correct that one of the reasons for using reloadables is lower cost over time.

Sooooo..... you have to make your choices and then take your chances. Some people, who are independently wealthy, like Phil and Milo, intentionally sacrifice whole rockets and motor systems to the rocket gods on a regular basis. When Milo was still flying rockets, his approach to a launch was to keep flying a rocket with a bigger and bigger motor until he lost it. Phil is slightly different, he tends to go for the biggest motor on the first flight.

Some of us, who grew up in a different generation and are NOT independently wealthy, take an entirely different approach. I carefully evaluate the launch site, the weather (wind speed and direction primarily), and the rocket that I intend to fly. Then I limit the size of the motor for the particular rocket to give me a flight that I have a high degree of confidence that I will be able to successfully recover the rocket in the confines of the launch site.

Sometimes.... I might take somewhat more of a risk, but usually then I will employ single use (SU) motors so that if I lose the rocket I won't lose an expensive RMS casing.

Another reason for using reloadables is the satisfaction that some of us get from assembling the reload. I will never never never forget the first reload I launched. It was an Aerotech 24mm RMS. The reload was an F12. I used it in an Estes Broadsword. Previous to that the largest engine I had used was an Estes D12. When my son pushed the button on the F12.... the noise, the smoke... and the rocket went up and up.... and up and up... and up. We were dancing around and hooping and hollering like fools.

However.... the best overall solution as far as I am concerned is to find a VERY LARGE launch site. Then load the max motor for the rocket and let'er rip !!!!
 
If you are just starting out with mid-power go with the single use motors (SU).

Although, in the 24mm size (same as the Estes "D" motor) there is a really wide variety of reload sizes.

You might want to wait before going to a 29mm sized reloadable motor system (RMS)

Forget about the 18mm RMS it seems to have become the abandoned step-child of Aerotech.

sandman
 
Bought my 1st reloadable (29/40-120) in 1998, and I am still using it today. I also have a 24mm reloadable, both of these cases are from Aerotech Consumer use inventory. I have lost the 24mm once to a rocket eating tree, and after a few rain and wind storms, the tree retuned my casing to me.

So lets see the pros and cons

cons:
expensive loss.

Pros:
cheaper per flight
wider variety of reloads
a step closer in bringing you closer to the sport of rocketry in reloading your own motors

I looked at a single use 29mm G40, in 1998 was priced at $14.95, and a G64 reload, then priced at $8.10

The 24mm reloads come (3) reloads to a pack, and cost $14.95 for F reloads (F24)... today, (2) 24mm F21's cost $21.95

For me it was the cost thing.

If you get a reload, there are precautions to take to insure that you get it all back.
-motor retention...with out a doubt, the easiest and most frequent way a flier will loose a reloadable. The motor gets spit out at Apogee, never to be seen again...not fun.
-Don't flie your reloadable in heavily wooded areas
-or on windy days

Right now reloads are scarce, but Aerotech's production is picking up slightly, and we will be in loads and singles again one day soon.

Johnnie Paul
 
My suggestion to not lose expensive RMS motor case, is to consider using either an altimeter for dual-deployment/dual stage recovery or engine ejection charge with either a timer or altimeter to get the same effect....the lower the altitude that the main recovery system opens, the better your chances of recovering the rocket and that expensive RMS motor case....
 
Thanks guys, this gives me a lot to think about and too look at. If I am getting the hang of this:

1. be selective when you use the RMS to lessen the chance of loss.

2. build a solid foundation about flight characteristics under different conditions.

3. Use in larger rockets using 24mm up

4. Use a system to track rocket

Alright, think I got it ... now to go learn something about the different motors and reloads.:)
 
I like my 18/20 case, and Aerotech has told me they do plan on making more loads for it soon... I have a D24 grain that needs replaced, and they said that they will send me a grain when they are ready.
 
With any luck, I will be getting a casing (or maybe 3 motor set) soon.
 
we have had sooo much fun with 18mm RMS and I've heard from at least three places (including above) that AeroTech wants to abandon the 18mm line. so I was glad to read n3tjm say they told him they will start making reloads again. I only have 8 or so left!

for example, my son put a D13-7 in his Custom Redliner. it totally blasted, rocksim guesstimated 2200' and we're certain it wasn't far from that! it shredded the decals off the fins, shed a tear!


that said, 2Walks if you want to get in to RMS start with 24mm. and don't count on saving any money with it, you'll just end up spending more on motors and bigger rockets. this is not a bad thing!
 
Originally posted by KenParker
<snip>......., or happens to land in the exact middle of a pond that happens to be inhabited by alligators (sorry, eugenefl...),
<snip>

Hey! That's still an open wound Sir! :mad: What made that rocket and camera a loss was that it was to be the first ever onboard video of an upscale Deuces Wild while on dual F21 power! The rocket happened to be autographed by Mr. Jim Flis himself. No worries, I'll dig through some of these old posts and find a KenParker sore spot! :p :D

Originally posted by KenParker

Some of us, who grew up in a different generation and are NOT independently wealthy, take an entirely different approach. I carefully evaluate the launch site, the weather (wind speed and direction primarily), and the rocket that I intend to fly.

....and bring along a man by the name of Miguel Cebollero (my dad). Everyone needs someone like him. ;) He seems to locate or assist in recovering rockets at every launch. He helped bring down Jim Flis's prototype Tres at a Florida meet in November.

MY PHILOSOPHY ON RMS:

In all fairness and in the perspective of daily life and financial priorities, a hobby is still going to be a hobby. The drain of funds and expenditure in the "R&R and morale" category will be depleted much quicker than say, going to dinner and a movie. I suppose the savings involved in reloads is relative to the overall scheme of how much you want to save while enjoying the hobby, but it is still a large expense and initial "investment" if it can be called that. In truth, I would go with the RMS casing and not worry too much about losing it. Losing rockets and rocketry related items is a part of the hobby despite any control we think we might have over what happens on launch day. Undoubtedly, precautions and common sense are to be taken to preserve the life of that casing, but the expectation on launch day is that something can and generally will go wrong. In a nutshell, if purchasing an RMS casing is going to be the cause of an arguement with the significant other in the household or the reason why groceries or bills aren't paid one week, don't do it. Because then and only then, if that casing is lost, the pain ignored in making that purchase initially will be felt when the casing is gone.
 
Originally posted by eugenefl
Losing rockets and rocketry related items is a part of the hobby despite any control we think we might have over what happens on launch day.

This probably sounds a little nieve, but the first thing that struck me when I started looking into rockets after seeing the discovery show, is how inexpensive it is. Not saying you can not or do not spend a good amount of money, not to mention time. Most hobbies have a pretty good chunk of cash outlay in the front end. This hobby a person can get into for an amount under $200.00 compared to most hobbies that I have had, many of those had an up front cost of $1,000's of dollars. Things like shooting hobbies, motorcycles, even working out in a home gym.

I think what would bother me the most is losing a $40.00 motor in a $15.00 rocket. :D
 
This hobby a person can get into for an amount under $200.00 compared to most hobbies

Two walks, that was my very observation back in 1997...I tried the RC airplane route: over $500 invested, and I still had to join the AMA, a local club, and buy fuel, so I was a coupla hundred dollars away from just learning how to fly...I got miffed for what ever reason, and sold everything I had, when I too rediscovered Rocketry. I was flying and part of a local group, that belonged to NAR, they provided everything I needed except a rocket and motors...allthough I seem to remember a gentleman who brought extra rockets and motors for visiting children at our launches...he thought everyone should fly. This in the span of a week of "offing" the RC outfit.

Pick your poison, Rocketry is easier to get into, but remember, a G80 single-use costs more than a gallon of Nitro RC fuel...all hobbies have there perks, do what you love.

When I 1st started flying my then new RMS casing, a fellow flier told me that "If you can't afford to lose it, don't fly it..." That is part of my evaluation when I look at the Aerotech Mustang, and say "G64-10 today?...yeah baby!":cool:


Johnnie Paul
 
I started out with the aerotech hobby level reload set
18mm ,24mm, 29mm

I thinks is the best deal(if you can find a set reasonably priced)

a great introduction and VERY versatile set.it allows you to fly quite a large range of rockets..plus It allows you to fly rockets you already have(with minimal ,If any mods)

for example the 18mm ,came in handy on my Bomarc clone ,,because I built it a little heavy...I wouldn't have been able to fly it(safely) on any estes motors

I would suggest to atleast get the 24mm and 29mm ,,lots of fun !!!

also grab up some single use loads when you have the funds or for that quick AP fix!
 
Originally posted by Johnnierkt

Pick your poison, Rocketry is easier to get into, but remember, a G80 single-use costs more than a gallon of Nitro RC fuel...all hobbies have there perks, do what you love.

Johnnie Paul

Another advantage cost wise that Rocketry has over a lot of hobbies is "adaptability". Most hobbies all most have a set cost every time you do them. With Rockets you can choose a propulsion system/rocket combination on any given day to fit, the amount you can afford to spend. If a little short on money use a rocket that uses 1/4A to c6 - if you feel you can afford it, then use a rocket with G80.

"If you can't afford to lose it, don't fly it..."

Great advice: :)
 
Adaptability...AMEN to that.

After reading all the posts, I may have to send Gary Rosenfield of Aerotech an email and see just exactly what his plans are for the 18mm reload...I would not mind having one of those myself...

Johnnie Paul
 
Well, if you loose a rocket with a RMS case, there is a greater chance you will find your rocket... since you will put a little more effort in retrieving it. I only had a couple RMS cases lost where I did not bother looking for it... simply because I had no idea what general direction it went. For example... My LOC Lil' Nuke... with a G104-10T. Major rod whiplass, went into the woods...
 
Originally posted by n3tjm
Well, if you loose a rocket with a RMS case, there is a greater chance you will find your rocket... since you will put a little more effort in retrieving it.

Good point: When I lose an arrow that I just put the feathers on, no paint, no finish, I spend a few minutes looking and then figure, heck I'll run into it next time. I had some very expensive custom arrows and when I lost one, I spent two days looking and was thankfull when I found it.
 
Originally posted by TwoWalks
I had some very expensive custom arrows and when I lost one, I spent two days looking and was thankfull when I found it.

I don't buy expensive custom arrows, the plain-jane ones are expensive enough. When I ordered a new dozen last year, I watched over my new babies extremely carefully. One shot went into the grass, and I thought I saw the arrow skitter off to the side through the tall grass. I spent waaaaay too many hours looking for it.
Turns out that what I saw shooting off to the side must have been a small rock that the arrow hit hard. My arrow actually went straight ahead, into a part of the yard I never even looked into. I finally found it a few weeks later with the lawn mower.
So much for my pretty new dozen.
 
Originally posted by powderburner
I finally found it a few weeks later with the lawn mower. So much for my pretty new dozen.

I have always been amazed at how much better my feet are at finding arrows, than my eyes. :D
 
I've got Easton XX75's and XX78's and some carbons, have always wondered how well they'd go up with a micro max motor, maybe half their length....

You guys tried anything like that yet?? would imagine the fletching should work ok as long as the motor isn't too overpowered...
 
Originally posted by firemanup
I've got Easton XX75's and XX78's and some carbons, have always wondered how well they'd go up with a micro max motor, maybe half their length....

You guys tried anything like that yet?? would imagine the fletching should work ok as long as the motor isn't too overpowered...

I have never tried it ... on the other hand I am still building my first rocket. Funny though because yesterday I seen some place on the net about making a rocket from a bic pen and thought, heck I could do that with an arrow. I agree the feathers should work just fine. The big problem would be getting the shoot into that small tube. :)
 
Originally posted by firemanup
I've got Easton XX75's and XX78's and some carbons....You guys tried anything like that yet??

I shoot mostly traditional/primitive (the competitions I participate in are limited to trad) so I don't have too much in the way of alum shafts. I did have a sack full of alum cut-offs from a local archery shop, I tried to GIVE them away (launch lugs? short MMX rockets?) but nobody seemed interested. So far, I am still flying the little plastic rockets that came with the MMX set-up. Someday I will give a piece of alum arrow shaft a try with MMX power, but I doubt that little motor will lift an entire arrow.
 
Another advantage to rocketry over other hobbies is the comraderie shared by its participants. I've never seen a hobby where everyone helps everyone else so much! I mean, you never have to be afraid to ask a question, and you will get an honest answer and people wanting to help as best they can.

As for the debate on RMS versus SU - in my opinion, RMS wins on all fronts. Great selection of motors and propellant types (WL, BT, BJ), cost, and fun level. Building a reload gives a great feeling of accomplishment, watching it fly is amazing. As far as losing the casings, as long as you're smart with choosing what to launch in a particular rocket given a particular launch area, risks are minimal. Just make sure motor retention is taken care of - in midpower, this is not as much of an issue - most kits will have hooks or whatever. I love my 29mm cases (40-120, 180, 240), and my 24mm case. I've only launched the 40-120, but the rest get taken out and loaded into rockets just to see how they look quite often. I'm pathetic, I know...
 
Originally posted by powderburner
I shoot mostly traditional/primitive (the competitions I participate in are limited to trad) so I don't have too much in the way of alum shafts.

Same here, shoot primitive I suppose - wood bows, wood shafts. Throw tomahawks and atlatl's ... now Rockets. :D now there is a real combination.
 
hey TwoWalks,

I just GOTTA know,
do you pronounce it "atl-atl" or is it "at-lat-l"

I have always been interested in those things, read about them a lot and found some good internet sites. Have to draw the line somewhere though, because I already have too much junk laying around the house and my loving spouse might hurt me if I started another hobby.

As far as a common thread, it's obvious: ballistics! Even back when I was flying (?!) radio-controlled model airplanes, my results were still largely ballistic.
 
Originally posted by powderburner
hey TwoWalks,

I just GOTTA know,
do you pronounce it "atl-atl" or is it "at-lat-l"


Actually both ways is correct: I say "at Latl"
That is actually the Aztec word for it ... in Australia it is Woomera and a half dozen other names.

First radio controled plane ... flew great, watched it disappear into the sunset. Second RC plane after three or four flights became ballistic. Expensive hobby, probably why I think I can deal with the loss of rockets, lawn darts etc and feel its a relatively inexpensive hobby. :)
 
Expensive hobby, probably why I think I can deal with the loss of rockets, lawn darts etc and feel its a relatively inexpensive hobby.

It is the labor of love that you cannot put a price on in any hobby, but a lawn dart can sure take it away:D
 
Originally posted by Johnnierkt
It is the labor of love that you cannot put a price on in any hobby, but a lawn dart can sure take it away:D

:D My new nightmare put into words :D
 
...insert JAWS theme song here...

Land Sharks are pretty wicked too, as long as they are away from the crowd. But lawn Darts ("Core samples") are by far the most common form of distruction...but none of these will do any damage to the RMS, or loose it.
 
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