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Motors vs engines

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tmazanec1

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Are those doohickies that propel rockets called "engines" or "motors"?
 

Bat-mite

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Age old controversy. Most HPR manufacturers refer to them as motors. Estes and Quest use "engines." People have tried to define the terms, but basically they are whatever you think they are.

Me, I used to say "engines" all the time when I was only familiar with LPR. As I moved up in impulse class, I started defaulting to "motors."
 

dr wogz

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I try to refer to them as 'Motors'.. I feel Estes is wrong.

why?

An engine is defined (loosely!) as a machine that make energy from mechanical means. the pistons pumping up & down to creat<script id="gpt-impl-0.5655488697115063" src="http://partner.googleadservices.com/gpt/pubads_impl_105.js"></script>e rotational motion & power, a steam engine doing pretty much the same work.. (has moving parts, that all work together to produce the desired work)
A motor is defined as a device that changes energies to produce power directly. An electric motor uses magnetic energy to produce rotational motion & power.. A chemical motor produces energy from a (controlled) chemical reaction..
 
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Nytrunner

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I loosely agree with Dr. Wogz.

Our solid propellant (guess I'll throw in some hybrids too) devices create a "Motive Force" in a pretty straight forward manner, so motor makes the most sense to me.

The complexity of mechanisms in Liquid rocket engines (and I'll throw some hybrids in here too) make the term "engine" applicable in my opinion. For the same reason that I squint and shake my head when I see the Wikipedia table of Rocket Motor Classifications with entries like "Falcon 9" or "Saturn V".
 
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Cabernut

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Propulsor?

I can't remember where I read that but I believe it was determined the most accurate description.

However... in common use, correct or not, I have noticed "engine" usually refers to black powder, where "motor" is used with composite.

I tend to use motor for all of them.
 

GlenP

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http://uh.edu/engines/
Makes me think of a cool radio show, The Engines of our Ingenuity produced by KHOU.
Necessity is the Motor of Invention?
 

jderimig

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Back in the day when steam was gaining popularity, thermodynamicists allocated machines that specifically convert thermal energy to mechanical work as "engines". Hence operators of such machines were call "engineers". All other machines that create mechanical work by converting other forms of energy, electrical, water wheels, wind etc were designated motors.
 

samb

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The father of model rocketry, Orville Carlisle, referred to his invention as a booster unit in a letter he wrote to some guy named Stine at White Sands in 1957.

Carlisle letter.png


For myself, toe-may-toe <==> toe-mah-toe.
 

dhbarr

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Going back to read Carlisle & Stine, my belief is that "propellant cartridge" is most correct, "motor" most common, and "engine" less frequent.
 
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Nytrunner

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"My rocket takes 38mm cartridges".
That actually sounds pretty awesome. Might even be more accurate too.
 

samb

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Estes has always sold engines:

1963:
Estes_1963_Catalog.jpg

2016:
Estes_2016_Catalog.jpg


Aerotech has always sold motors:


1990:
Aerotech_Catalog_1990.jpg

2016:
AT_Catalog_Updated.jpg
 

Bat-mite

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Let's get every single rocketeer in the English-speaking world together at one launch, and have a big tug-of-war to settle it once and for all.
 

Exactimator

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Are those doohickies that propel rockets called "engines" or "motors"?
That's a good question. Another good question is what does CATO stand for? Next time you're bored, ask that one.

ETA: I have a friend in the engineering field who asks about my rockets. If I call the engine a motor (or a motor an engine, I can't remember which way) he gets visibly annoyed and flaps his arms around while explaining to me something about "potential." He's easy to screw with.
 
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dr wogz

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Let's get every single rocketeer in the English-speaking world together at one launch, and have a big tug-of-war to settle it once and for all.
that would be cool!!

And the 2nd round would be Cato vs Cato (Kah'-toe vs Kay'-toe) :D


I'm gonna see what the French term is tonight; what is printed on the Estes motor packs, when I get home. I beelive it will be "Moteur" meaning Motor / Engine
 

shreadvector

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Which is why the Space Shuttle had liquid fuel Rocket Engines and solid fuel Rocket Motors.

Mass drivers are motors - transverse linear motors.

https://en.wikipedia.org/wiki/Linear_induction_motor

https://en.wikipedia.org/wiki/Mass_driver

Ask the Narn about mass drivers.





I try to refer to them as 'Motors'.. I feel Estes is wrong.

why?

An engine is defined (loosely!) as a machine that make energy from mechanical means. the pistons pumping up & down to creat<script id="gpt-impl-0.5655488697115063" src="http://partner.googleadservices.com/gpt/pubads_impl_105.js"></script>e rotational motion & power, a steam engine doing pretty much the same work.. (has moving parts, that all work together to produce the desired work)
A motor is defined as a device that changes energies to produce power directly. An electric motor uses magnetic energy to produce rotational motion & power.. A chemical motor produces energy from a (controlled) chemical reaction..
 

shreadvector

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NFPA says "Motor".

California law was changed to correct the term from"engine" to "motor".

Toy companies should not be used as a definitive source for a technical or scientific term.
 

ThirstyBarbarian

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People will know what you mean, regardless of which term you use. I used to say engine, because that's what it said on the package, but now I prefer motor. What do you call the thing that makes a car move? Motor or engine? I would usually say engine. But what about the thing that makes a motorcycle go? Hmmm...

One thing I do know for sure: This R2 unit has a bad motivator.
 

Nytrunner

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Ask the Narn about mass drivers.
I was really confused for a couple seconds until it finally clicked. I rarely run into B5 appreciators.

I prefer Catastrophic Take-off for CATO. Comes in motor, stability, and airframe flavors!
 

John Beans

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Even rocket scientists argue this one, so hard to call a winner.
My arbitrary preference is:
1. Motor = provides work
2. Engine = provides work and has moving parts
So in my explanation you have an Estes motor and a SpaceX engine.
 

Bat-mite

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Hmmm ... more and more, I'm liking "drive cartridges." :wink:

Or, Jeffries Tubes!
 

shreadvector

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gizza2

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I had this conversation with Gary Rosenfield at Lucerne Dry Lake in the early 80s. His opinion was that 'engine' definitely implied mechanical motivation so he preferred 'motor' and I concur based on that logic.
 

rstaff3

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Now I'm confused. Do you have a gas engine on your motor boat?
 
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