Motors D - G

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term_paint

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Hi I am just getting back into the hobby after along time away. My question is probably fairly simple....I would like to get some ideas to the following.

1) Is it better to use a reloadable motor? Cost, Reliability, Etc?? And if so can someone suggest a brand/model..

2)If it is best to use a one time motor can someone also give there opinion as to what works best.. Cost, Reliability, Etc?? And if so can someone suggest a brand??

Basic questions but if it is best to purchase a reloadable motor i would like to do that first thing and it is solved and behind me...

I will be using the madcow rocket series to start.....Thanks.
 

jj94

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For mid power rockets (E-G, but I tend to include D too), Aerotech is the way to go, in my book. Cesaroni came out with their Pro29 line not too long ago, but doesn't have too many mid power reloads out. Reloads are so much more cost effective after using a case around 5 times, and so I use them the most. SU is just too expensive per motor.
 

shreadvector

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Aerotech is the way to go for the D-G range you are asking about. The variety of different motor loads is quite good and you can select the correct thrust level and delay times for most any model. AND the delay time can be adjusted down for heavier models if you bought too many of the longer delay times (which is the most common error/problem).

You need to NOT lose the casing! They are expensive - even when you buy the 3 pack from Hobbylinc or the low price 18mm casing from ValueRockets.com.

Make sure that if you build Estes models that you file or cut the upper portion of the motor hook so that the top of the RMS motor will fit the mount. Ditto for peeling the inside of the thrust ring.

https://www.valuerockets.com/default.aspx

https://www.hobbylinc.com/htm/aro/aro91849.htm
 

n5wd

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Is it better to use a reloadable motor? Cost, Reliability, Etc?? And if so can someone suggest a brand/model.....
And while it's true that (assuming you re-use the case enough to amortize the cost of the case) re-loadables cost less per flight, there's also some downside:
1. It takes a certain amount of competence to put the motor together correctly. It's something that, if you get in a hurry or become careless or get distracted, and do a step improperly, you can cause a big problem and destroy the casing and rocket.
2. We often joke about the "bonus delay" of Aerotech motors - even if the motor seems to be put together correctly, sometimes the delay is inconsistent (possibly due to some grease on the delay grain, it often seems). It's much rarer for a single-use motor to have inconsistencies in the delay, though it does happen.

IMHO something like the new Cessaroni 29mm system offers a good compromise between the advantages and disadvantages of reloadables... less chance to mess things up, due to the design of the reloadable, but you still have the cost advantage.
 

Tom W

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Another consideration is the time required between flights. If you have an hours drive each way and have to pay to use the field how many flights do you want to make in a day to make it worth the trip?

I also enjoy watching other people's flights which can be done while cleaning casings but not assembling motors (for me anyway). So I don't consider the maintenance as a 'waste of time'

I use both - reloadables to keep the costs down and single use if I want to get 1-2 more flights in before I go home.

Sometimes you have to wait the day out for decent weather and when it gets good I want to fly rockets not build motors.

Tom W
 
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jj94

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Another consideration is the time required between flights. If you have an hours drive each way and have to pay to use the field how many flights do you want to make in a day to make it worth the trip?

I also enjoy watching other people's flights which can be done while cleaning casings but not assembling motors (for me anyway). So I don't considering the maintenance as a 'waste of time'

I use both - reloadables to keep the costs down and single use if I want to get 1-2 more flights in before I go home.

Sometimes you have to wait the day out for decent weather and when it gets good I want to fly rockets not build motors.

Tom W
Once you get used to building motors, it doesn't take long for Aerotech's midpower loads at all. It only takes a few more minutes for one flight on RMS vs. a flight on SU. Further more, it's even faster if you prebuild some of the motor's parts. By that I mean by installing the grains and such in the liner, greasing most of the parts, and assembling the delay assembly before leaving the house. So at the field, all you have to do is slip in the liner and delay along with the o rings and insulator.
 

Bazookadale

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1. It takes a certain amount of competence to put the motor together correctly. It's something that, if you get in a hurry or become careless or get distracted, and do a step improperly, you can cause a big problem and destroy the casing and rocket.
My TARC kids, some as young as 12 all easily learned to assemble reloads with no problems - I on the other hand am fumble fingered and greatly prefer single use

2. We often joke about the "bonus delay" of Aerotech motors - even if the motor seems to be put together correctly, sometimes the delay is inconsistent (possibly due to some grease on the delay grain, it often seems). It's much rarer for a single-use motor to have inconsistencies in the delay, though it does happen.
Bonus delays are a "FEATURE, not a FLAW"
 

Zeus-cat

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Personally, I don't think the D reloads are really worth the effort as Estes makes a black powder D12 in 24mm. I'm sure some people love them and they work great in specific rockets, but once I burn up the D9's I have I doubt I will get any more. I like the E and F reloads in the 24mm size and a friend of mine likes the 29mm G motors.

I am like some of the other people here who require a few minutes (or more) to put together a reload. You really need to pay attention the first few times you do it, but once you get it figured out it isn't too bad. It is probably a good idea to get someone to show you how to do it or to assemble one while an experienced person watches you. I find the instructions provided with the reloads to be too long and not very clear.
 

MarkII

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Reloadable or single use? Composite propellant or black powder? Or hybrid? The correct answer to these questions is "all of the above!" It really depends on what you are flying (and for hybrids, whether you are certified at Level 2). The great thing about having such a plethora of motor choices is that you can gain experience with a variety of commercially-prepared propellant technologies and motor systems, and that you have lots of options when you want to have your rocket perform within a given set of parameters that you have chosen. So my advice? Don't rule any of them out; try all of them while you continue to ask for opinions and ideas. You will learn what you like and what you don't like, and what works best in various situations. Having more experience is always preferable to having less.

To get a sense of how various types of motors work in various types of situations, attend some launches. Also, read build threads and flight reports here and read reviews and flight logs over at EMRR. Additionally, check to see if there is a club in your area and see if you can take in one of their launches. Check out videos of launches on YouTube and on various personal and club websites. (Do a Google search for "rocket video" and "rocket launch video.") And, if possible, drop in on a launch or two. Keep talking to other fliers about their experiences with various motors and types of motors. And did I also mention going to some launches?

MarkII
 

jj94

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Personally, I don't think the D reloads are really worth the effort as Estes makes a black powder D12 in 24mm. I'm sure some people love them and they work great in specific rockets, but once I burn up the D9's I have I doubt I will get any more. I like the E and F reloads in the 24mm size and a friend of mine likes the 29mm G motors.

I am like some of the other people here who require a few minutes (or more) to put together a reload. You really need to pay attention the first few times you do it, but once you get it figured out it isn't too bad. It is probably a good idea to get someone to show you how to do it or to assemble one while an experienced person watches you. I find the instructions provided with the reloads to be too long and not very clear.
I'd have to agree about your opinion on the D reloads. However, I can't see myself getting Estes D's again. I got a pack or two of them, and they honestly aren't too exciting for me. But AT's 18mm RMS is sooooo worth the money. They're great for punching 18mm rockets up to their full limits, and if I ever want to launch a 24mm rocket on a D, I'll just use the 18mm D's with an adapter. If you're interested in using composite D motors as well, the 18mm D's hit much harder. The 24mm D9 takes some time to reach full thrust and it doesn't even have too much punch to it at all for those heavier rockets. The 18mm D13 and D24 reach full thrust very quickly and are good for those heavier rockets as well. I haven't flown the 24mm E and F reloads yet, but they sure do look fun. Also, just as it is with the 24mm D vs. the 18mm D's, I think it's just the same with the 29mm E vs. the 24mm E's. The 29mm E just isn't worth the money, and you can get more out of the 24mm E's. There are more choices for the 24mm case as well. I haven't flown the 29mm E before, but I can conclude this from their thrust curves and what others say about them. Also, I heard the 29mm E takes quite a bit of effort to ignite, but I forgot the reason why. Maybe someone in here can chime in and explain the rest. :)
 
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