Quick Reference Chart for Rocket and Engine Selection?

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bibbster

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Hey gang!

I had started to make a spreadsheet for me and my daughter to use that would show us at a fairly quick glance, what LPR uses which engines. I thought it would be handy to sort it by engine sizes, etc., but after getting into the meat of it, I wondered if anyone else has already created such a chart?

Ideally, I would be able to see which of our rockets shared the same engine, so when we went shopping we would be able to get the best 'bang for our buck'. :D

Any thoughts or help would be greatly appreciated.

Best,
Jeremy
 
I'd be willing to bet that someone around here has one. However, since there are so many manufacturer's of model rockets, a single list would be very long. You might be better off making one yourself that suits your own ends.

If you are strictly talking Estes, then AC Supply does a good job of arranging rockets by motor class. https://www.acsupplyco.com/estes/beta.htm
 
Hmmm, a sheet cross-referencing rocket to motor,..... That's going to have some pretty big variance depending on how people build their rocket.
Maybe going by kit recommended motor? That would work for Estes kits, but not all manufacturers give such recommendations (knowing that people modify and finish builds differently)

About the best I could offer is the Lazy RSO's motor guide I cooked up last year (Really need to finish the last 2 volumes)
 
I guess I should specify for kits. All the ones we have bought so far all have recommended engines to use, but I guess when we run across one that doesn't we'll be here with an inquiry. :)

John, thanks for the AC Supply link. That will help me a bit.

Nytrunner, thank you for the link to your engine guide as well. Good stuff from the quick look I gave it.

I guess I'll trudge on with my spreadsheet, though the multi-stagers sure do throw a wrench into things. :\
 
I use Thrustcurve.org. Enter your rocket spec's into the program and it will tell you what motors work for that rocket, and give you a realistic delay, which is really handy for the smaller Estes rockets. Lot's of other info. there, check it out:
https://www.thrustcurve.org
 
The nice thing about with Thrust Curve is that you can export results to a spreadsheet. If you are really goo with Excel, I imagine you could merge multiple sheets, then create pivot tables for sorting by engine type or rocket name, etc. Never tried it.
 
I'd say I am pretty goo with Excel, but not good. ;) :lol: That will be the ticket so that I can select one engine and see all the rocket we have that it will work with.
 
I'd say I am pretty goo with Excel, but not good. ;) :lol: That will be the ticket so that I can select one engine and see all the rocket we have that it will work with.

No-shame-if-it-feels-goo.jpg
 
That's a good spreadsheet. Adding a list of rockets in the arsenal would be what I am looking for. That way when we are at the launch field, we can easily see which engines go to which rockets...and also at the hobby shop.
 
I think he's more going for something like, "I have a box of C6-5s. Which of my fleet can I put them in?" Or, "I have ten rockets in my fleet. Can I put the same motor in all of them?"

I used to have one, but I never had more than five rockets at any time, and so it was easy to maintain. Also, I'd lose at least one rocket per launch, buy another, and constantly have to change my sheet. :facepalm:
 
I think he's more going for something like, "I have a box of C6-5s. Which of my fleet can I put them in?" Or, "I have ten rockets in my fleet. Can I put the same motor in all of them?"

I used to have one, but I never had more than five rockets at any time, and so it was easy to maintain. Also, I'd lose at least one rocket per launch, buy another, and constantly have to change my sheet. :facepalm:

That's exactly what I am looking to do, John.

We currently have 28 rockets with 2 more on the way, so a spreadsheet of that nature would be very helpful. (Hangs head in shame and walks away) :facepalm:

I've got all the data entered but it needs some fine tuning.
 
I realize that my perspective is totally different from most fliers, and I hope I don't come off as bragging, but here is how I handle multiple rockets/motor selection.
I have over 50 rockets that were built with repeatability foremost in my mind. Some have dozens of flights, some only a few, depending on how much I like them, or how easy they are to prep. Each rocket has a folder in a 3 ring binder, with several binders for low power, high power, inactive and destroyed/lost.
When I prep for a launch, I decide which rockets I want to launch based on the launch. Waiver altitude, ground conditions and host club are all factors in this. When I have a list, I pull out the folder and go over my previous flights with each rocket, which is recorded after each flight. A lot of my favorite rockets have favorite motors, like my dual deploy Argent, which has 15 flights on an H115 dark matter. If I want to change that, I look at the thrustcurve printout in the folder and determine if another motor will work.
Sharon and I stockpile motors, we have a Google doc. with a list of them. It's a bit embarrassing when people come up to us at a launch and ask us if we are vendors. Most of you go to a launch and buy a motor for a rocket you want to fly. You could use the same thrustcurve printout to see if the motor your vendor has will fly in that rocket. Or, if you have a smart phone or Ipad, bring up thrustcurve and check it that way. All my rockets are on there, except for clusters, which thrustcurve won't support.
When I go to a launch, I'm there to fly rockets, not prep rockets. I usually bring 15 rockets ready to fly for a weekend launch, and fly 12 of them. Sharon is slightly more conservative and might only fly 10. All those rockets are prepped here at home. We buy motors based on what we flew last year, with some additions based on what we plan to build in the off season. If I didn't log my flights, none of this would work. Plus, at my age, I can't remember what I had for lunch yesterday, so how am I gonna keep track of all this other stuff?
So, here's some advise from an old guy that flies a LOT of rockets.
1.) Take notes, your learning curve will be a lot shorter, and you can claim to be a rocket scientist!
2.) Use Thrustcurve.org, it does most of the science for you.
 
Not a braggart at all, Wayco. It's good to get others ways of doing things. It helps to get the thoughts flowing, and in this case, provides another possible solution to my 'problem'.

We currently also have a binder that we keep pics of the builds, the insert card if there is one, as well as the instructions. On the back of the insert card we write down the day we completed it, first flight information, etc., so you are not off base at all.

Seems like your 1.) and 2.) are what we're after. I'm quite certain that we won't ever take our entire collection to launch day, so prepping at home is definitely the easy way to go as far as having the right engines for the rockets we want to launch.

While shopping, in store or online, the spreadsheet will help us to get the best bang for our buck, rather, purchase engines that will cover the majority of our fleet.

Thanks for your input!
 
I realize that my perspective is totally different from most fliers, and I hope I don't come off as bragging, but here is how I handle multiple rockets/motor selection. I have over 50 rockets that were built with repeatability foremost in my mind. Some have dozens of flights, some only a few, depending on how much I like them, or how easy they are to prep. Each rocket has a folder in a 3 ring binder, with several binders for low power, high power, inactive and destroyed/lost. When I prep for a launch, I decide which rockets I want to launch based on the launch. Waiver altitude, ground conditions and host club are all factors in this. When I have a list, I pull out the folder and go over my previous flights with each rocket, which is recorded after each flight. A lot of my favorite rockets have favorite motors, like my dual deploy Argent, which has 15 flights on an H115 dark matter. If I want to change that, I look at the thrustcurve printout in the folder and determine if another motor will work. Sharon and I stockpile motors, we have a Google doc. with a list of them. It's a bit embarrassing when people come up to us at a launch and ask us if we are vendors. Most of you go to a launch and buy a motor for a rocket you want to fly. You could use the same thrustcurve printout to see if the motor your vendor has will fly in that rocket. Or, if you have a smart phone or Ipad, bring up thrustcurve and check it that way. All my rockets are on there, except for clusters, which thrustcurve won't support. When I go to a launch, I'm there to fly rockets, not prep rockets. I usually bring 15 rockets ready to fly for a weekend launch, and fly 12 of them. Sharon is slightly more conservative and might only fly 10. All those rockets are prepped here at home. We buy motors based on what we flew last year, with some additions based on what we plan to build in the off season. If I didn't log my flights, none of this would work. Plus, at my age, I can't remember what I had for lunch yesterday, so how am I gonna keep track of all this other stuff?So, here's some advise from an old guy that flies a LOT of rockets. 1.) Take notes, your learning curve will be a lot shorter, and you can claim to be a rocket scientist! 2.) Use Thrustcurve.org, it does most of the science for you.

I'm going to pull up at Holtville Havoc and yell at you.

[video=youtube;IRsPheErBj8]https://www.youtube.com/watch?v=IRsPheErBj8[/video]

And for the OP: I use Thrustcurve religiously. The data it spits out will also give you a list of motors that DON'T work because the speed off the rod is too low. It's a good safety check.
 
I'm going to pull up at Holtville Havoc and yell at you.

[video=youtube;IRsPheErBj8]https://www.youtube.com/watch?v=IRsPheErBj8[/video]

And for the OP: I use Thrustcurve religiously. The data it spits out will also give you a list of motors that DON'T work because the speed off the rod is too low. It's a good safety check.


You made me laugh :lol:

OP: I'm the Sharon in Wayco's post. I may be slightly more organized than Wayne (there is another term for it but I'm going for PC) .

I have a low power binder and a high power binder. In the front of the lower power binder is additional field data such as the data sheets for the Estes Altimeter I put in my Low Power rockets to check altitude - which is helpful to verify the coefficient of drag setting I use in Thrust curve; and data sheets on how to use various camera's I fly on the rockets, on how to put together Jolly Logic Chute Protector, on the various trackers that are used to find the rockets - stuff like that which you need to have readily available in the field.

But more to the point of your original question, in the front I have my launch sheet for the rockets I have prep'd to fly for that particular launch, written in the order I plan to launch them, any mitigating circumstances (such as don't launch this one if winds are over 10 mph), the motor, the anticipated altitude and the NS. In front of all that is my master sheet for the year tallying NS, type and size of rocket motor , flights etc. This is handy to see how many of what motors I fly often which sure helps when it comes to Black Saturday each November. Seeing what you actually DID DO is valuable.

Each folder section contains a pocket in which I keep my Thrustcurve printout, with the parachute size and color for that rocket. Prior to each launch I write up the launch card and keep it in that pocket so all I have to do is date it and take it up to the RSO.

Another advantage to Thrustcurve is all the rockets (except our two stages) are listed in one place for quick reference.

Which reminds me I gotta get into the rocket room this evening and finish getting rockets set up for our local rocket launch this weekend and the Holtville Havoc next weekend



A quick shout out to the folks who created and maintain the thrustcurve.org web site: Thank you!
 
Not a braggart at all, Wayco. It's good to get others ways of doing things. It helps to get the thoughts flowing, and in this case, provides another possible solution to my 'problem'.

The simple solution to your problem is to fly the rockets you have and keep track of the motors you use. This works great when you only have a dozen rockets, most of which are Estes kits that fly 18 & 24mm black powder motors. Once you start leaving out the thrust ring at the top of that PS 2 kit, the spreadsheet will get awkward. Now you want to buy those big 29mm reloads....

We currently also have a binder that we keep pics of the builds, the insert card if there is one, as well as the instructions. On the back of the insert card we write down the day we completed it, first flight information, etc., so you are not off base at all.

You are on the right path here, just broaden your horizons a bit. The insert card is too small to document what happened on that flight, and if you had a problem, what you did to correct it for the next flight. Now we are getting to the rocket science.


Seems like your 1.) and 2.) are what we're after. I'm quite certain that we won't ever take our entire collection to launch day, so prepping at home is definitely the easy way to go as far as having the right engines for the rockets we want to launch.

I saw the list of rockets in your build pile, so you are totally correct, you will never bring even half of the rockets in your collection. If you are really committed to never buying anything bigger than an "E" motor, having the right engine is as easy as this:
002_3.jpg


It's when the little thrust ring at the top of your motor mount tube comes off that things can get out of hand....
003_3.jpg


Don't even ask what is in the big black container....

While shopping, in store or online, the spreadsheet will help us to get the best bang for our buck, rather, purchase engines that will cover the majority of our fleet.

Getting the most bang for your buck is buying what you fly when it's on sale, like the Wildman's black Saturday sale:
007.jpg


The forum will also help with this, having a thousand rocketeers looking for a good deal usually ends up being posted up somewhere on TRF. At your level, knowing about hobbylinc.com, sirius and AC supply is a good place to start.


Thanks for your input!

You are welcome.

Since my loving wife decided to join in, I just have to add in this pic:
005.jpg


She is totally into organizing and documenting EVERYTHING!
 
The nice thing about with Thrust Curve is that you can export results to a spreadsheet. If you are really goo with Excel, I imagine you could merge multiple sheets, then create pivot tables for sorting by engine type or rocket name, etc. Never tried it.
That's exactly what I did, don't even have to be an Excel nerd- the troublesome part is adding new rockets to your fleet, but it's just time consuming at that point, not hard.
 
In my early BAR days, I made a table with the motors I had. Using OpenRocket decided which rocket went with each motor. (kind of the opposite of your question) That worked until the fleet grew, then I found out about Black Weekend sales.

Now I really need to make a binder as described above....
 
Wayne and Sharon (I have friends named Wayne and Sharon), thank you VERY much for your input. I'm glad to be getting this information now while we are just getting started. It'll be much easier to implement some of your processes now rather than later.

Rocket number 29 and 30 are shipping today so I'm already having to tweak our spreadsheet. :lol:

By all means, please share any other thoughts that might help my daughter and me get the most enjoyment out of keeping motors and rockets straight. Good stuff from everyone in this thread! Hopefully it will help others as well.
 
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