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ezgb59a
08-25-2008, 06:42 PM
New to the board ... first posting.

Back in the early to mid 70s I built an Estes Rocket. It was a "military" rocket but not the Pershing. You painted it army green and the nose cone wasn't as sharp pointed as the Pershing. It was supposed to take C size rockets however if you didn't insert the engine mount you could fit a D size engine in the tube.

Anyhow - I'm looking for the name and if possible trying to find the plans for this rocket. My son is building rockets in 4H and I figured I would rebuild one of the ones I built.

Thanks
ez ...

Race58
08-25-2008, 07:14 PM
First,,
Welcome to the forum!
You will find a lot of very nice,knowledgeable and helpful people here.

To answer your question it might be an Honest John.

http://www.dars.org/JimZ/k-27.htm

Chas Russell
08-25-2008, 07:38 PM
The Honest John was my take on it, although the only Pershing model was a maxi-brute. A standard Estes HJ with a D...hmmmm.

Chas

Race58
08-25-2008, 07:47 PM
Yeah they made a Maxi Brute Honest John too which used "D's"

http://www.ninfinger.org/~sven/rockets/nostalgia/78est046.htmlThe Honest John was my take on it, although the only Pershing model was a maxi-brute. A standard Estes HJ with a D...hmmmm.

Chas

Chas Russell
08-25-2008, 08:23 PM
Race58: I have two original Maxi-Brute Honest Johns and two or three of the re-released version. The original comment was about taking out the engine mounts for "C"'s and putting in a "D". I was just trying to note that Estes did not produce a small Pershing model.
On the other hand, Roachwerks does...

Chas

ezgb59a
08-25-2008, 09:01 PM
I looked at the picture Race put up and I think the Honest John is a bit tall.

The rocket I made had more of a plain nose cone - rounded. Didn't flare out like the HJ rocket. The one I had was maybe 12 inches tall.

Thanks
ez

mperdue
08-25-2008, 09:20 PM
Perhaps the Little John. It was powered by 18mm motors and was shown painted olive drab in the '75 catalog.

Mario

Royatl
08-25-2008, 09:22 PM
First, I would suggest that you go to:

http://www.ninfinger.org/~sven/rockets/rockets.html

and look through the Estes catalogs posted there.

But the only rocket I remember with military styling that had a blunt nose and could take either C or D motors was the A-20 Demon, though it was primarily painted yellow.

http://www.ninfinger.org/~sven/rockets/catalogs/estes75/75est18.html

If that's the one, the nose cone can be purchased from Semroc (www.semroc.com). Everything else is a pretty straightforward BT-55 based rocket, and you can find plans for it at http://www.dars.org/jimz/k-58.htm .

Quasar
08-25-2008, 09:25 PM
It may be the Little John. It came with a mini-engine mount, but a D engine would fit in the body tube if the mount weren't installed.

http://www.ninfinger.org/~sven/rockets/catalogs/estes75/75est6.html

ezgb59a
08-25-2008, 09:57 PM
Little John is the rocket. Great web site - thanks for giving me the link.

After looking at all of those pictures I can recall each of the rockets. I sure thought the Little John took Cs ... but what the hey. I just inserted the motor mounts and let it fly with Ds - probably a tad higher than expected.

We built them in a shop class then went out and shot them up. Lots of the guys got the Javelin and Super Flea. Lots of them bought the Mosquito.

How hard is it to get good plans for these old rockets to recreate them? I'm going to go through the 75 and 74 catalogs and see which others I remember.

I'll gave to show this to some in our 4H group - they'll love it. I was fortunate in living within 10 miles of the Estes facilities. Lots of school trips out there and unless the wind was really blowing always a free rocket launch - many times with one of the big rockets.

I don't live to far from Argonia KS where they launch those super rockets - rockets that get up there 1000s of feet. Will have to make the trip one of these days. I've heard they will launch over Labor Day.

Thanks guys - !!!
ez

CPMcGraw
08-25-2008, 10:12 PM
...How hard is it to get good plans for these old rockets to recreate them? I'm going to go through the 75 and 74 catalogs and see which others I remember...

You came to the right domain! :D

Check out the PLANS (http://plans.rocketshoppe.com) area for Ye Olde Rocket Shoppe...
And check out JimZ (http://www.dars.org/jimz/rp00.htm)...

Welcome to our asylum, BTW!

Solomoriah
08-25-2008, 10:12 PM
Plans are mostly EASY to come by. Many are right here (well, close to right here):

http://www.oldrocketplans.com/

And many are on JimZ's site:

http://www.dars.org/jimz/rp00.htm

Have fun!

Solomoriah
08-25-2008, 10:13 PM
Gah. You beat me.

CPMcGraw
08-25-2008, 10:14 PM
Gah. You beat me.

Like minds...

Frightening, ain't it? :eek:

Race58
08-26-2008, 12:41 AM
I beg to difer.
If you look at my first post and go to the link you will see that Estes did indeed make a smaller 18mm version of the Honest John the K-27 kit.
If you didn't use the 18MM mount and use the body tube which was a BT 50 you could adapt it to a "D" motor.Race58: I have two original Maxi-Brute Honest Johns and two or three of the re-released version. The original comment was about taking out the engine mounts for "C"'s and putting in a "D". I was just trying to note that Estes did not produce a small Pershing model.
On the other hand, Roachwerks does...

Chas

barone
08-26-2008, 07:41 AM
I beg to difer.
If you look at my first post and go to the link you will see that Estes did indeed make a smaller 18mm version of the Honest John the K-27 kit.
If you didn't use the 18MM mount and use the body tube which was a BT 50 you could adapt it to a "D" motor.
Hey Ed....Chas was talking about the Pershing......not the Honest John.

chanstevens
08-26-2008, 08:24 AM
Little John is the rocket. Great web site - thanks for giving me the link.

After looking at all of those pictures I can recall each of the rockets. I sure thought the Little John took Cs ... but what the hey. I just inserted the motor mounts and let it fly with Ds - probably a tad higher than expected.

We built them in a shop class then went out and shot them up. Lots of the guys got the Javelin and Super Flea. Lots of them bought the Mosquito.

How hard is it to get good plans for these old rockets to recreate them? I'm going to go through the 75 and 74 catalogs and see which others I remember.

I'll gave to show this to some in our 4H group - they'll love it. I was fortunate in living within 10 miles of the Estes facilities. Lots of school trips out there and unless the wind was really blowing always a free rocket launch - many times with one of the big rockets.

I don't live to far from Argonia KS where they launch those super rockets - rockets that get up there 1000s of feet. Will have to make the trip one of these days. I've heard they will launch over Labor Day.

Thanks guys - !!!
ez

FWIW, I just built a clone of the Little John, and plan on flying it this weekend. I'll put a Rocksim file of it up tonight when I get back home (file's on my home PC). It took a good deal of nose weight, though, to make stable on a C and I'd think it would be unstable on a D, especially a D12 versus something like a D18 or D21, so you'll definitely want to check you CG before playing around with one today.

FWIW, if you are planning on a trip to a larger launch site, you might also want to look at Mad Cow Rocketry--they make a 2.6" diameter verson of the Little John. That's one thing that has changed quite a bit while you were out of the hobby--today there are dozens of wonderful vendors online (and/or at major launches) that tend to fill niches in the market. You can find an amazing variety of designs both old and new out there, as well as materials for designing or cloning on your own.

--Chan Stevens

ezgb59a
08-26-2008, 07:26 PM
FWIW, I just built a clone of the Little John, and plan on flying it this weekend. I'll put a Rocksim file of it up tonight when I get back home (file's on my home PC). It took a good deal of nose weight, though, to make stable on a C and I'd think it would be unstable on a D, especially a D12 versus something like a D18 or D21, so you'll definitely want to check you CG before playing around with one today.

FWIW, if you are planning on a trip to a larger launch site, you might also want to look at Mad Cow Rocketry--they make a 2.6" diameter verson of the Little John. That's one thing that has changed quite a bit while you were out of the hobby--today there are dozens of wonderful vendors online (and/or at major launches) that tend to fill niches in the market. You can find an amazing variety of designs both old and new out there, as well as materials for designing or cloning on your own.

--Chan Stevens

Question - what is "CG" ... what is a Rockism file?

The only thing I remember, when that engine ignited that rocket took off and as high as many of the lighter rockets that others had made. The teacher - though I don't think he would have cared at all - was a bit surprised. He had done rockets for years and probably expected the rocket to go up just a ways.

Yes lots of things have changed ... and one thing I don't care about are the pre-assembled rockets where you glue a plastic set of finds to the bottom of a tube. I know they are trying to get younger kids involved.

Thanks

chanstevens
08-26-2008, 07:49 PM
CG=center of gravity, the balance point of the model. Fully loaded with engine, it needs to be forward of the center of pressure (CP) by at least as far as a body diameter. Your next question is probably how to measure CP, and that would be a whole 'nother thread. I'd at least start building a mini rocketry library starting with an old classic from when you were last flying--The Handbook of Model Rocketry.

Given your expressed aversion of the nearly completed plastic rockets, you might want to point the browser to semroc.com or fliskits.com. Both are outstanding companies that promote "old school" construction techniques. Semroc specializes in retro-repros, or modern reintroductions of classics. Flis specializes in, well, wierdness--very innovative ad imaginative designs, such as a 6 foot rocket made of foam cups with an optional parasite boost glider (gotta check out my all time favorite, the Acme Spitfire). Thre are plenty of other great vendors out there as well, but these two will probably be right up your alley.

Solomoriah
08-26-2008, 07:55 PM
Question - what is "CG" ...
Center of Gravity. One of the two key components of a rocket's stability, the other being the Center of Pressure. I remember first studying those concepts in the old Centuri catalog's model rocketry guidebook insert.

You do know that many of the old catalogs and other documents are archived on Ninfinger's site? It's here:

http://www.ninfinger.org/~sven/rockets/rockets.html

what is a Rockism file?
Rocksim is a popular program that many rocketeers use to design rockets. It can simulate a rocket's design, telling you center of pressure and center of gravity, and simulate flights on a variety of commercial engines. It has its limitations, but it's the best thing going. But it's about a hundred bucks... and every time I have a hundred bucks to blow, I buy a box of parts.

Mark II
08-26-2008, 08:37 PM
Question ... what is a Rockism file?
Thanks
http://www.apogeerockets.com/rocksim.asp

The days of pencil-sketched model rocket designs and back-of-the-envelope Barrowman calculations are pretty much gone now. This program replaces and automates all of that. RockSim is useful for all types and power levels of hobby rocketry. And the rise of high-power rocketry made the need for such rocket simulation software even more compelling. On this forum and elsewhere, you will often see "RockSim design files" (with the .rkt extension) included in posts as attachments. These contain the list of components for the rocket, a diagram of where the components are located (i. e., how the rocket is assembled), a 3-D computer-generated image of the resulting design, and, most important, a list of flight simulations of the rocket design that the design's author generated with the software. These usually include flights with various motors, often under various weather conditions, and include a wealth of detailed information about each flight. This information, including things like maximum altitude, time to apogee, acceleration, optimal engine delay, and time to landing and distance from the launch pad, are not just ball-park estimates. Depending upon the quality of the information that the user has entered (and obtaining and entering good to excellent quality information is quite easy), the predicted results range from very good to phenomenally accurate when they are compared to subsequent real-world performance. The RockSim design file is a compact, easy to share format for communicating quite a lot of information about a particular rocket, and it is an industry standard now. Most hobby rocket fliers trust the program's results so much that they make heavy use of it to help them select the correct motors and motor delays for their rockets and their launch conditions. (For example, I order motors from vendors based on the results I get from my RockSim simulations.) Unfortunately, you do need to be running the current version of RockSim to read these files, but the web page mentioned at the top of this post includes a link for downloading a free trial of RockSim 8, the current version. Finally, Apogee Components, the company that makes RockSim, is quite simply a great company to deal with.

Mark \\.

chanstevens
08-26-2008, 10:02 PM
Attached is the Rocksim file for a BT-50 based Little John, used about 20 grams of nose weight to get it stable enough to handle a C. On a D12, the margin drops to about 0.4, so not something I'd fly in any kind of wind whatsoever...

I've also posted a screen shot of the Rocksim 2D design view, so you can see what the software does for us. The [M] is the mass I added for nose weight, the bullseye is the CP and the circle with two pie wedges in it is the CG. On your model, whatever the size, you'll want to make sure the CG is about where I show my CG (with motor loaded).

Race58
08-27-2008, 12:24 AM
DUH!!! :o

Should have RTW%Q.

Sorry!Hey Ed....Chas was talking about the Pershing......not the Honest John.