Just returned to Rockets after 25 years, Need some help

Like many young kids, I built, launched, blew up and lost dozens of rockets in my childhood. I remember the days of cannibalizing parts from crashed rockets to assemble some new and improved design I had come up with while sitting through my elementary social studies class. I would slap it together, stuff whatever rocket engine I had laying around in there, jump on my bike and head for the local farmers field to see what it could do. I launched many rockets with wet paint, wet glue and other various symptoms of an impatient youth. Now that I am "grown up" I feel that I may have over-corrected. The rockets I am building now take weeks to complete, have a mirror finish are meticulously assembled. So much, that I often do not want to launch them out of risk of losing all of that work.

I have a young son who is interested in space, stars, rockets, etc... We have started building some level 1 rockets together and have had several successful launches with 100% recovery rate and minimal damage. We are currently building a Mini Honest John kit. I had the original honest john years and years ago, and it was an awesome rocket. I still have most of it. It is probably repairable, but I worry that again, I may lose it if returned to service. I will just buy another kit and fly that one most likely. Anyway, back to the story. We are working on the Mini Ho-Jo, its a pretty nice kit. It is all assembled, weight has been added to the nose cone, etc... I sorted through all my piece and parts and I scratch built an identical Mini Ho-Jo only one that takes the 18mm family of motors. I used my wife's Cricut to design and cut my motor mount parts.

As a kid, I never paid any attention to center of gravity, balance, etc... I just glued them up, let them rip. My question is this....

Where should my balance point be on this rocket? How do I know how much weight to add in the nose? Do I find the balance point with the engine in or out? I am not a rocket scientist, I am a forester. There is a reason I did not become an engineer.

Any help would be really beneficial. My kids rockets are built according to the instructions so that they don't go all crazy ivan on them. I am just a bit more adventurous on my rockets.

Thanks for the help! I think I will spend a lot of time on this forum.

Welcome to the forum. My suggestion is to download the free OpenRocket sim program. There are sim files out there for just about every rocket made. OpenRocket will help you figure out the stability of your rockets and decide which motors will work. The center of gravity (CG) should be determined with the motor you intend to fly mounted. Have fun.

Welcome back to rocketry, and to the forum.

For simple hobby rockets, if you don't want to take the time to do computer simulations, you can do some simple tests to see if your rocket has a reasonable margin of stability. This link explains it better than I can.

Enjoy!



https://www.rockets4schools.org/images/Basic.Rocket.Stability.pdf

+1 Bill nailed it better than I could explain ( I talk a lot with my hands-kinda like fighter pilots do-LOL!) Welcome back to the smoke! It only fair to tell you that you'll get nagged to post pics and videos. I'm giving you fair warning-we are a group of enablers and junkies that thrive on rockets of all sizes. The only thing better than a picture of a rocket is a picture of two rockets...

Thanks Everyone! this is exactly what I was looking for!

That is the reason I have come here. When I ask my wife "should I get the Saturn v or the Mercury Redstone?" I just get the look....

When I ask that question here, you respond "Get both". My kind of people!

As soon as I figure out how to post pictures, I will do so. Thanks again!

number of ways you can go...starting with finding the cg of model with the mini-motor(ready to fly) and then add weight to the big motor rocket until its' cg matches. a quick and dirty method, take the weight of a C6-5 subtract the weight of a mini motor, then take the difference and add that to the nose(in addition to any noseweight that Estes calls for), that should get you close enough.
Rex
the redstone is a fairly nice rocket, the nose cone may drive you to distraction though .

Excellent idea on figuring out the CG. I will definitely try that out.

My dad has a redstone from the late 60s hanging in the basement at their house. It is about 50% complete. Very neat rocket. I have 2 of them in the package waiting for my time and commitment. I have a Saturn 1B, Bullpup 12d, cosmic interceptor, Nova, Alien Space Probe 3, Space Racer and several other rockets in the package just waiting to be started. I must have really gone through a period of picking up really cool rockets. Then I probably got into girls or something totally distracting.

I figure I will knock out a few more basic rockets with the kids, then tackle some of the more time consuming and difficult rockets of my own.

I am looking for a nice sized Saturn V kit if anyone has any suggestions. it seems like the 15-20" models are somewhat affordable, anything larger than that are extremely costly.

There is a book that's an easy read and quite helpful to the questions you have asked and a bunch that you will soon be asking somebody.
The Handbook of Model Rocketry.
you can get a used copy on Amazon for under 10 bucks, $15 new or on Kindle.
https://www.amazon.com/gp/product/0471472425/?tag=skimlinks_replacement-20

It covers all the basics, plus opens you up to staging, clusters, gliders, scale.
Anyhow, it's a good book, well worth you reading it and might be good for your son when he gets to that age.

Sprucejedi said:

Excellent idea on figuring out the CG. I will definitely try that out.

My dad has a redstone from the late 60s hanging in the basement at their house. It is about 50% complete. Very neat rocket. I have 2 of them in the package waiting for my time and commitment. I have a Saturn 1B, Bullpup 12d, cosmic interceptor, Nova, Alien Space Probe 3, Space Racer and several other rockets in the package just waiting to be started. I must have really gone through a period of picking up really cool rockets. Then I probably got into girls or something totally distracting.

I figure I will knock out a few more basic rockets with the kids, then tackle some of the more time consuming and difficult rockets of my own.

I am looking for a nice sized Saturn V kit if anyone has any suggestions. it seems like the 15-20" models are somewhat affordable, anything larger than that are extremely costly.

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Estes is re-releasing the Saturn V kit this June. It's listed in their 2016 catalogue.

+1 on OpenRocket. Below is a sample of a simulated rocket. It clearly shows the CP, CG, and margin of stability. You can then also simulate launches under various wind conditions and with different motors.

Sprucejedi said:

Thanks Everyone! this is exactly what I was looking for!

That is the reason I have come here. When I ask my wife "should I get the Saturn v or the Mercury Redstone?" I just get the look....

When I ask that question here, you respond "Get both". My kind of people!

As soon as I figure out how to post pictures, I will do so. Thanks again!

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Welcome!

Sound's like you're (you and your son) our kind of people too!

Now, I'll see if I can help enable you from here (in China... (where I teach English))

Tutorial Uploading Images to TRF w Flickr

"Using The Rocketry Forum" Tutorial

Is there a rocket club nearby? Launching on your own is fun, but launching with others is much more fun. And you will learn a lot.

Zeus-cat said:

Is there a rocket club nearby? Launching on your own is fun, but launching with others is much more fun. And you will learn a lot.

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No, unfortunately I am not aware of any local rocket clubs. We live about 4 hrs from my parents and we were down there last weekend to visit. We took all of our recently finished rockets and launched several times throughout the afternoon. It was like being 10 yrs old again with my dad. It was a lot of fun. My son's birthday is coming up and he wants a space themed party. We threw down the family rocket challenge. Everyone builds, everyone launches, everyone has fun.

My sister lives in Wichita, and they were telling me about a large model rocket get together that is put on out that way. It may be something to try and attend in the future.

I checked out some different sites and have a wish list put together for my future builds. It is funny, all the rockets I used to drool over in the catalogs as a kid but could never get due to them being too expensive, I now have most of them ordered or already own them. Better late than never!

I always wanted a nice V2, Patriot Missile, Phoenix Missile, etc... I found a place that has the V2 kit for sale, I will likely grab one soon.

I am currently fighting the Michigan weather. I tried to touch up my paint job real quick and now I am back at square 1. 8 inches of snow today, not ideal for painting.

Sprucejedi said:

I checked out some different sites and have a wish list put together for my future builds. It is funny, all the rockets I used to drool over in the catalogs as a kid but could never get due to them being too expensive, I now have most of them ordered or already own them. Better late than never!

I always wanted a nice V2, Patriot Missile, Phoenix Missile, etc... I found a place that has the V2 kit for sale, I will likely grab one soon.

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You are DEFINITELY in the right place! Please Post Pics!

Should you buy a Saturn V, do not fly it on a D12-3. I seen several get trashed from not enough power. Not sure if it was listed as the lowest recommended motor back in the day. Maybe the new ones will have a 29mm mount.

Should you get into bigger stuff, the new materials, electronics for deploying chutes, reloadable motors, etc. It is a lot to take in.

Most of the Estes stuff will pretty much be the same. Maybe more plastic nose cones than balsa would be my guess.

I am not real sure that I will get into the real serious type of stuff. I have always stayed pretty entertained with the standard offerings from estes. I get a little creative with them, but nothing too crazy. I can see it real easy to put a ton of money into this stuff, and that's just not something I want to get into. If I trash a 20$ kit rocket and lose some time, no big deal. I am mostly doing it because my kids are interested, and I had such a good time as a kid.

Its just as much fun as an adult, except I have a little more money than when I was 10 yrs old.

Sprucejedi said:

I am not real sure that I will get into the real serious type of stuff. I have always stayed pretty entertained with the standard offerings from estes. I get a little creative with them, but nothing too crazy. I can see it real easy to put a ton of money into this stuff, and that's just not something I want to get into. If I trash a 20$ kit rocket and lose some time, no big deal. I am mostly doing it because my kids are interested, and I had such a good time as a kid.

Its just as much fun as an adult, except I have a little more money than when I was 10 yrs old.

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There are people into all aspects of rocketry - something for everyone. Most of the major changes in the last 25 years are on the bigger items. There are also many other low power kit manufacturers besides just Estes you will see as well. No shortage of kits to build!

Sprucejedi said:

Its just as much fun as an adult, except I have a little more money than when I was 10 yrs old.

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I was visiting my parents when my son pointed to one of my old rockets... that was in 2011...


things escalate .... quickly.... one day you're launching a Big Daddy, thinking "this thing is huge..."

Then you meet this guy named Tim.....

the N.A.R. website lists several clubs in MI https://www.nar.org/find-a-local-club/nar-club-locator/ perhaps one of these would be close enough for a occasional visit. I would imagine that most clubs would enjoy spectators.
Rex

DizWolf said:

I was visiting my parents when my son pointed to one of my old rockets... that was in 2011...


things escalate .... quickly.... one day you're launching a Big Daddy, thinking "this thing is huge..."

Then you meet this guy named Tim.....

Click to expand...

Or find yourself looking at the work of a guy named Mike Fisher...

Sprucejedi said:

I am not real sure that I will get into the real serious type of stuff. I have always stayed pretty entertained with the standard offerings from estes. I get a little creative with them, but nothing too crazy. I can see it real easy to put a ton of money into this stuff, and that's just not something I want to get into. If I trash a 20$ kit rocket and lose some time, no big deal. I am mostly doing it because my kids are interested, and I had such a good time as a kid.

Its just as much fun as an adult, except I have a little more money than when I was 10 yrs old.

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That sounds familiar, now I am in the planning stages of smuggling an altimeter into the house without attracting unwanted attention from SWMBO. I can hear it now, "Why did you spend $40 just to boil eggs? You can do that with your watch!"

Welcome back to the hobby Sprucejedi ! You don't need that " ... doing it because my kids are interested... " story around here. We are mostly Born Again Rocketeers who have discovered that the secret to eternal youth is the smell of burnt black powder. Sounds like you are well on your way to amassing a build pile. Hobby Lobby is a nice local source for Estes kits and engines if you have one nearby, and their 40% online coupon makes for some nice bargains.

Sprucejedi said:

...

My sister lives in Wichita, and they were telling me about a large model rocket get together that is put on out that way. It may be something to try and attend in the future.

...

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If that's Wichita Kansas then your sister is referring to the Kloudbusters club in Argonia (https://www.kloudbusters.org/). Their annual AIRFest during Labor Day weekend is one of the premier amateur rocketry events in the country.

Hi Sprucejedi,
Welcome back to the hobby!
Stop by my building blog for some building ideas, do a search under "tips" for some old and new ideas.
www.modelrocketbuilding.blogspot.com
I try to do a build post or two every day.

Welcomes to rockahaulics anonymous! It sounds like you will quickly become a junky like the rest of us. Last year I said I wanted to move slowly from LPR to MPR, and now I'm planning to fly a 7'5" rocket this weekend.

samb said:

If that's Wichita Kansas then your sister is referring to the Kloudbusters club in Argonia (https://www.kloudbusters.org/). Their annual AIRFest during Labor Day weekend is one of the premier amateur rocketry events in the country.

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That's the one!


Whew, now that I know I don't need to hide behind my kids to mask my adult rocketry enthusiasm, I feel better.

Hobby lobby is a great place. The closest one is about an hour away, but we get up there regularly. There is a neat little hobby shop here in town that carries some good stuff. Always good to support them too.

Sprucejedi said:

That's the one!


Whew, now that I know I don't need to hide behind my kids to mask my adult rocketry enthusiasm, I feel better.

Hobby lobby is a great place. The closest one is about an hour away, but we get up there regularly. There is a neat little hobby shop here in town that carries some good stuff. Always good to support them too.

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Hopefully you know about the Hobby Lobby 40% off coupon? Great for buying expensive stuff like motors, kits, and launch equipment. I never walk in the stor without one.

Bat-mite said:

Hopefully you know about the Hobby Lobby 40% off coupon? Great for buying expensive stuff like motors, kits, and launch equipment. I never walk in the stor without one.

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Oh yes. I have a couple printed out and in the car for any unplanned hobby lobby visits. So far they haven't had anything real exciting on the shelf. But I'm hoping they rotate their inventory somewhat regularly. And I'm sure as the weather improves they will get more.

One thing that has changed is that there are now different sized guide rods and different launch systems for different sized engines. What's that all about?

It is based on the weight of the loaded rocket, and how much the rod can expect to bare without flexing, especially in a breeze. When the rocket bends back and forth on the rod, we call this "rod whip." The answer is to move to a thicker rod. However, once you get to MPR and HPR, most launchers use a rail system. Instead of a lug (straw) on the rocket, you have a button that slides into a square rail. Much sturdier.

There is a microrail for LPR rockets. Do a forum search to see examples. The bigger sizes are 1010, 1515, and unistrut.

You want a Saturn at a price you can afford?

https://drzooch.com/

There are way more companies than Estes. Check out the Rocket Resources pinned at the top of The Water Hole page. Not only are there companies with kits but more parts companies than you'd believe to make up those rockets you dream up.