Centuri Excalibur - Goony "Sting"

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GlenP

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In a nostalgic trip down memory lane, I decided to commemorate the second model rocket kit I built, from the Centuri Big Shot launch set, the Excalibur. ("Screaming Eagle, Screaming Eagle, Screaming Eagle." What about Excalibur?)

I have started doing some cardstock experiments to make a mini-sized clone, roughly 60% scale, but kind of got diverted from that into building a Goony-style version using a BT-5 as through-tube/upper body, combined with an empty TP roll for the bottom tube. I built the transition and centering rings from
PayloadBay.com templates and the BT5 nose from the Project Paper thread (really cool templates, THANKS!).

I made a fin template using Inkscape (www.inkscape.org) based on the full-size fin dimensions.

I wasn't really planning this out, it was sort of a impromptu build, so I don't have a printable template for the rocket, I kind of made it up as I went along. The BT5 tube was rolled around a 0.5" dowel with a layer of wax paper double-sticky taped to it. I used about 2 full wraps of 65# paper 11" long for the through tube. The TP roll was wrapped with the 65# paper.

I printed the decal sheet in solid black on the same color paper and literally cut and pasted them in place. The chrome wrap was from a roll of that tape used for dryer ducts.

The Arthurian legend inspired the name of the extra long beginners rocket, so for the Goonified short version, I was inspired by the somewhat shorter blade from Tolkien's Hobbit, "STING" I am almost surprised that no one has already come up with this before now.

here are a few pictures of the Goony build in process. Not sure what criteria a clone has to qualify as a Goony, but you almost have to retain the signature feature of the Excalibur transition in the caricature, I tried to capture that.

Still working on my 60% scale templates, I built a prototype on white copy paper and just roughed out some color ideas with markers. The Semroc parts (not the actual kit, that should be back in stock in the spring) from eRockets are also shown on the table, I plan to build that original full size version later.

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this 1974 catalog picture was used as a rough guide:

Picture 9.png
 
getting back to the mini downscale clone, here are a few pictures of the work in progress.

The inspiration for the red/yellow/black color scheme comes from this old catalog picture:
Picture 15.jpg

Here are the tubes and fins carded up
DSC_6318.jpg

for size comparison with the full-size Excalibur: tubes, transition and cone, SEMROC parts from eRockets. (and the Goony style mini version)
DSC_6320.jpg
=======update=============
color block and color swoop:
colorblockswoop.jpg
 
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perusing through the old catalogs for interesting color schemes for the Excalibur I came across one more to clone with my cardstock template. This was for the Excalibur 2 the one rare color image I could find.
Excalibur2.png

I have not downscaled the Booster 8 to a mini engine yet, that is on my agenda. For now, here is another incarnation of the Excalibur mini downscale cardstock STING, part deux!
Sting2.jpg

=update=
Excalibur 2, I mean STING DEUX, with the cardstock Booster 5, my fin color does not match the catalog picture, but the original instructions say to paint in bright colors to make it easier to find, and this will match my other color schemes as well. Now I am thinking it's time for a BT5 GROOVE TUBE. Rather than using the typical foldover card stock template, I prefer for the Excalibur clones to laminate multiple layers of the cardstock, this matches the original fins and you get a nice white edge that you can color with a marker to match the design or leave it white or whatever color paper you used. If you do the fold-over with cereal box cardboard you get a grey edge and it does not take to the marker as well. I made my booster tube a little short in my template, so I had to add a little extension to it, I will adjust my printable template for next time. The grey color portions will get covered up with chrome tape.
Booster5.jpg
P.S. the display stand is a prototype for a cardstock design. since the Booster 5 has an engine block at the bottom the display stand tube won't fit into the bottom of the booster. I had to turn the stand sideways and put the booster on one of the stand's tapered feet. A mini engine in the sustainer acts as the coupler between the booster and sustainer stages for this min-dia BT5, will need to friction fit the sustainer engine.
=======update========
image.jpg
I thought this would go well with the Booster 5
 
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Many thanks, Leo! I hope you find some useful info here when you get around to painting your Excalibur!

So here are my printable templates in Scalable Vector Graphics (SVG) format. You can use the free software InkScape or other popular illustrator software to make edits if you want. I went through the old catalogs and the facecard that I could find on-line and tried to interpret each design as best as I could. It helps if you have some experience in cardstock model building before building one of these. I have just done the artwork here, not balanced them for flight, I imagine you should add some clay to the nose as is typical for similar kits of this size. Feel free to make any updates, constructive feedback is welcome.

Now, I present to you, STING!
View attachment STING_SVG.zip

The bottom tube can be rolled around a 0.5" dowel with a single layer of wax paper taped around it, this is a BT5 size. Make a test tube to make sure your tube will fit a mini engine, or use a few mini engine casings taped together. The upper tube can be rolled around a 7/16" dowel covered with wax paper, not quite a BT4 size but close. If you want to use a different cardstock nose cone, take your favorite BT5 nose cone and scale it down 91% for this top tube.

screen grab, this is sort of how they look: (don't print this, use the .SVG files in the .zip above)
Picture 3.png
 
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for those of you who prefer PDF format

View attachment Sting2_WhiteGreen.pdf
View attachment Sting2_Booster5.pdf
View attachment Sting_RedYellowBlock.pdf
View attachment Sting_RedBlueSwoop3.pdf
View attachment Sting_RedBlueSwoop2.pdf
View attachment Sting_facecard.pdf
View attachment Sting_1979green.pdf

Enjoy! If you asked me which was my favorite, I would have a hard time picking one. I was initially inspired to replicate the red/yellow/black color block scheme, but found the simplicity and sharpness of the white/green Excalibur 2 really sleek looking also. After rolling these and hitting them with some satin clear laquer, they really shine. I have to decide on a paint scheme that I will use for my original full size Semroc/eRockets Excalibur parts build, I have some ideas for that one ... more on that later.

The templates do not have a part for the shoulder of the transition, see how the nose cone shoulder is made from the Project Paper nose cone instructions on this forum, make a similar shoulder for the transition part to fit in the bottom tube and feather cut it and glue to the transition.
 
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So, if you are going to build a Booster 5 for the mini Excalibur 2, then you are going to want a Groove Tube to go with it, right?

View attachment GrooveTube_FinTubes_inside.pdf
View attachment GrooveTube_FinTubes.pdf
View attachment GrooveTube_Booster5.pdf
View attachment GrooveTube_Body_Nose_NoLogos.pdf

print the fin tubes, then flip the paper and print again for the tube insides. launch rod won't fit in the gap between tubes, so you will have to install a launch lug inside one of the fin tubes for this mini clone.
 
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OK, so I finally got this out of my system. Excalibur mini has his little brother now. Big Shot mini. I need to re-print the decals on ink-jet waterslide paper and put them over a foil sticker to really match the original Screaming Eagle, will get to that later.
View attachment ScreamingEagleNoDecal.svg.zip
View attachment ScreamingEagleNoDecal.pdf
BigShotMini.jpg
that is not a cardstock nose on the Screaming Eaglet, it is from the Estes BT-5 nose cone pack. Perfect fit for the rolled cardstock BT5 tube.

Not that I am one to dwell in the past, I like the new kits from Estes too, the Tandem X is a great modern-day Big Shot combo launch set. I bought one of those for my son. But, yeah, once in a while I dwell in the past. There is enough room in my heart and my garage for these retro repro clones as well as the latest models from all the great model rocket vendors still in business today. Let's keep them in business.
 
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Launch report, camera battery was dead, so I did not get any video, but I was able to launch the mini Groove Tube on 1/2A3-4T and it was a perfect flight. I filled the nose cone with some play dough covered in white glue. Straight up, maybe 150 ft or so, nearby streamer recovery within a soccer field. A great New Year's Day launch. I had misfires for the Sting and mini Eagle, I think the 9v battery was getting low, will have to try again. That mini Groove Tube was really groovy, but not too Far Out, just right for a small field rocket.
 
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GlenP:

The Excalibur and the Excalibur 2 were part of my original fleet back in the late 70's. I did get one from semroc and it is now painted white. I wanted to recreate the one with the " swoops " but could never figure it out. I will be using your patterns to recreate decals for my Excalibur. Many thanks for figuring this out. I also checked the other files and they look great.

- R_R
 
I still have a bag of SEMROC parts from eRockets to build an original size Excalibur, have not gotten to it yet, mine first one was lost long ago. The Swoop designs are just my interpretation of what the far side of Excalibur looks like, from past catalogs we don't have any pictures of that side (a la Apollo 8's first trip around the moon) so I made up two possible versions.

One alternative to masking and painting those color swoops would be to use the self-adhesive Trim Monocote.

Might be crazy thinking, but I was going to try to make a 2-stage version, and then with the Booster it would actually be an Excalibur 3. The 10" body tube is about the limit for gap staging. Might go with a 18mm or 24mm tumble booster fin can to 18mm main body with rear-eject streamer, to 13mm upper sustainer. Since those fins on the top sustainer are kind of small, I could keep the transition attached for some extra cone-fin and base drag stability, haven't worked out the design details yet, just a concept for now. Not sure how heavy it will get with all the extra stuff in there.
 
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