Okay kids, let's set the WABAC machine for January 2005. After complaining about the price of RockSim for two years, I finally scraped together the necessary cash and bought Version 7 for $95.

I think the first design I implemented in RockSim was a 1.36X BT-55 upscale of the Estes Wolverine #0861. It wasn't long before I started making designs that looked cool, but were impossible to "flight test" in RockSim, given the combination of my enthusiasm and inexperience with the software.

Quite by accident, I discovered that 8 Semroc/Centuri ST-5 body tubes fit nicely around an ST-8 tube. Then, to add insult to injury, I found that an ST-20 would slip around the ST-5x8 + ST-8 assembly. Note picture #1 below. The ST-5 tubes in the "real" models are 3" long, while the ST-20 is 1" long, and centered in the middle of the 3" tubes' length.

One thing led to another, and I came up with the initial design for a rocket I called "5820," (picture #2) pronounced "Fifty-Eight Twenty." ('Cause the body tubes were ST-5, -8, and -20, y'see...) I sat down to build it in earnest, and ran into some smaller than regulation size ST-8 body tubes I'd bought from Totally Tubular *years* before. In the process, I realized that there wasn't *nearly* enough room for a recovery system in the 6" long ST-8 body tube, and decided to Do Something Completely Different(TM).

In recent months I briefly considered using the 5820 tube and ring fin assembly on another rocket, and then chose not to. Fastforward to about 3 weeks ago, when I decided to see if I could put 3 1/2 years of RockSim experience to work on this particular design. I chopped off the front end, since I needed more room for the recovery system, and came up with Version 2 (see below).

About 10 days later, I decided to apply two of Bruce S. "teflonrocketry1" Levison's techniques to the "5820" design: Ring fins and tube fins. I managed to implement them early this weekend, and got the first version that didn't flip end over end -- Version 3. But then I decided while there was *lots* of room for parachutes, shock cords, etc., it still was one of the ugliest things I'd ever seen.

So I decided to make the ST-8 shorter, and ran a longer ST-7 core tube down the center of it. Then for good measure, I added a clear payload bay up front. That gave me Versions 4 and 5, and I decided to apply the now-functional ring and tube fin assembly to Version 1.

That's when disaster struck. I tried to add some commercially available nose weights to the foward end of the original 5820, and it refused to become sufficiently stable. So I decided to leave well enough alone (he says, after FIVE versions of the same rocket!), and release 4 of the 5 on the unsuspecting YORF public.

So I present to you the following Variations on a Single Theme:

5820 A -- Original (for history's sake)
5820 B -- ST-8 Extended with CPT-8 Payload Section
5820 C -- ST-7 Core Tube
5820 D -- ST-7 Core Tube with CPT-10 Payload Section

My typical files will follow in individual posts for each design.

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Attached Thumbnails

         

__________________
Jay Goemmer
"Centuri Guy"/"Tau Zero"
YORF Member 28
Semroc SAM #0029
NAR 86131


"I think about organizing things all the time. Never seems to happen. I find something that piques my interest and I'm off on a quest. Or a Centuri. "

--Bill Eichelberger, 02/22/2022


“Centuri fret buzz in an updated form.”
Bill “Wallyum” Eichelberger re: Estes Flutter-By
03 Sept 2014

This is where it all started. Maybe I'll try upscaling it and using a very *long* piece of poster board for the outer ring.

With bigger tubes, I can use bigger screw eyes for nose weights, and maybe get it stable at last. (insert maniacal laughter here)

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Attached Thumbnails

   

Attached Files

5820_A.rkt (53.7 KB, 60 views)

__________________
Jay Goemmer
"Centuri Guy"/"Tau Zero"
YORF Member 28
Semroc SAM #0029
NAR 86131


"I think about organizing things all the time. Never seems to happen. I find something that piques my interest and I'm off on a quest. Or a Centuri. "

--Bill Eichelberger, 02/22/2022


“Centuri fret buzz in an updated form.”
Bill “Wallyum” Eichelberger re: Estes Flutter-By
03 Sept 2014

Here's a longer ST-8 tube, complete with added payload section and *really* strange nose cone.

This one is stable at 1.02 calibers on a C6-5. (A bigger screw eye would help remedy that. )

.

Attached Thumbnails

   

Attached Files

5820_B.rkt (93.4 KB, 53 views)

__________________
Jay Goemmer
"Centuri Guy"/"Tau Zero"
YORF Member 28
Semroc SAM #0029
NAR 86131


"I think about organizing things all the time. Never seems to happen. I find something that piques my interest and I'm off on a quest. Or a Centuri. "

--Bill Eichelberger, 02/22/2022


“Centuri fret buzz in an updated form.”
Bill “Wallyum” Eichelberger re: Estes Flutter-By
03 Sept 2014

Yeah, that PR-78 paper transition on Versions 4 and 5 (or "C" and "D," if you prefer) will probably give fits to those of us who are Not Quite as Adept as James Pierson , but here you go anyway.

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Attached Thumbnails

   

Attached Files

5820_C.rkt (85.6 KB, 59 views)

__________________
Jay Goemmer
"Centuri Guy"/"Tau Zero"
YORF Member 28
Semroc SAM #0029
NAR 86131


"I think about organizing things all the time. Never seems to happen. I find something that piques my interest and I'm off on a quest. Or a Centuri. "

--Bill Eichelberger, 02/22/2022


“Centuri fret buzz in an updated form.”
Bill “Wallyum” Eichelberger re: Estes Flutter-By
03 Sept 2014

To quote my buddy Adam who grew up in "BAWston, Mass.," "That is wicked AWEsome!"

Have you ever seen a payloader that looks like *this* one? I can't say that *I* have, at least until now.


--Ladies and gelatin, I give you... BARCLONE design Number 500.


Craig, buddy, there's my "personal throwdown."

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Attached Thumbnails

   

Attached Files

5820_D.rkt (94.7 KB, 67 views)

__________________
Jay Goemmer
"Centuri Guy"/"Tau Zero"
YORF Member 28
Semroc SAM #0029
NAR 86131


"I think about organizing things all the time. Never seems to happen. I find something that piques my interest and I'm off on a quest. Or a Centuri. "

--Bill Eichelberger, 02/22/2022


“Centuri fret buzz in an updated form.”
Bill “Wallyum” Eichelberger re: Estes Flutter-By
03 Sept 2014

Jay,

I am officially crediting you with 5 designs, as there are sufficient differences between each of the 5280 variants to call them individuals, and as I really want to get the 500 mark passed as quickly as possible.

In fact, you have now been given the (dubious) distinction of creating the 501st entry, which means we now have the first design in the second group of 500. We now only need 499 more entries to reach the new goal of 1000 designs!

I'm going to be counting on you, Jay, to help us reach the new goal quickly. Just think - one new design from you each week, together with James and me, will give us 156 designs each year!

So grab your notebook and start doodling. Even one new design a day is not beyond the realm of impossibility, and is a worthwhile exercise. It puts the old mass of oatmeal up there through its paces, without hurting too much.

Congrats on the victory, Jay!

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635

Jay,

Don't forget to add the launch lugs!

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635

Seems like I've seen that nose cone used somewhere before...

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635

500 designs reached finally and I still have 12 or so saved for Christmas.

Jay, I need some info on your 5820 design series. I have always avoided using the ST-8 tube cause I could not figure out how to get the ST-7 motor mount tube to center in it. I see the 5820 design series is using centering rings. Please educate me to these centering rings and I will add one more wonderful part to my database.

James Pierson
NAR# 77907

I can help out here, James. I've done this in "the wild" a few times. It's not a true centering ring, but a couple or so wrap thicknesses of label stock. The fit is either very tight, or a little loose depending on the thickness of the paper and how many layers of wrap you use. YMMV on the number of layers, in other words.

It still shows up in RockSim as a centering ring, however...

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635