Estes Logo Rocket... No idea how I'm gonna do it...

[Marc_G]

Hi folks,

Consider if you will the Estes logo:



In my 2+ years as a BAR, I've never seen a rocket shaped quite like the venerable Estes logo. I've seen cone-shaped rockets, and from what I understand they are stable. Haven't tried hard to sim in Rocksim yet, but hopefully I'll figure that out.

But for my next creative build, I'm going to attempt to create a rocket that's conical with stubby little triangle fins just a little ways up from the base. This all started when Sandman made some decals for me and threw in some that are the usual Estes logo but with "MARC G" in place of Estes. Estes, please don't sue me for trademark infringement. :wink:

I have a conical BT-55 nose cone, so the rest of the rocket will be designed around it. I've measured the angle of the cone and traced it out on some paper:



So now I have to figure out how to build the dang thing. I've never worked with paper transitions but I suppose I could make up some centering rings of various diameters around a BT-55 core and roll a paper/cardstock cone shape. I'm thinking to make this rocket do rear-eject recovery so that I don't have to sweat the body-to-nosecone transition too much.

Also thinking about some sort of light foam sculpted into a cone shape and covered with a paper wrap for smoothness. Lathing out some balsa is probably out of the question due to lack of equipment and skill, and I want to keep this light enough to fly on single 18mm engines.

The rocket will eventually be painted with white rusto epoxy paint, because I have a can I never used, and want to use up. And I can let it cure plenty long, since we're on burn ban here...

I'm puttering around with this but would appreciate any insights you guys might have. There's no rush. I will probably intersperse this build with an Estes Hornet. Why? Because I feel like making a black and yellow rocket...

Marc

 

[Rocketbuilder]

I actually just recently realized that the logo was not the front a rocket with canard fins. :blush:
As far as building it, I think you are right that paper transitions with centering ings are the way to go. You could make the cone out of poster board, of you wanted. They cost about a dollar each, and it might look better.
If it ends up being too heavy for 18mm motors, maybe you should fly it on a white lightning reload to better simulate the logo.
Good luck!

 

[Coop]

Almost seems worth it to foam out and laminate, though I don't know how well that'd work with your 18mm powerplant limit...


Later!

--Coop

 

[JPVegh]

I think cardstock and c-rings is the way to go, sort of an upside down 2 minute egg kind of thing. If you design it open rocket your transitions will be laid out for you to print, although paper size might be an issue depending on the size of the transitions.

Ready made styrofoam cones are available at the craft stores but accurately boring a hole through the center of one might be tougher than you think. It depends on what kind of tools you have and how precise the cones are.

I would probably start by measuring out the logo rocket with calipers to get the correct proportions then scale it to work with the nose cone you want to use. You could ditch the noce cone altogether and make the whole thing a cardstock cone with rear eject.

 

[JStarStar]

Kinda like the Semroc (Centuri) "Point" with a set of short pointy fins.

Make the cone a deeper angle and build the interior of the rocket pretty much the same.

 

[dave carver]

I think it was Estes's idea of a Sprint surface to air missle...something I "seem" to remember.

https://www.designation-systems.net/dusrm/app4/sprint.html


Found it

 

[Rocketbuilder]

Keep in mind that the logo implies the rocket is traveling away at an angle, so you can make the cone a little less pointy and say it's accounting for perspective.
I agree that if you want to fly it on 18mm motors, you might have to ditch the nose cone and build it smaller and less pointy.
Edit: Oops, I meant more pointy.

 

[Marc_G]

Great input, everyone! Thanks.

I'm exploring several options. Last night I cut out some foamboard squares which will eventually become centering rings. I'll see what they weigh in aggregate plus the cone and body tube, and compare with Max liftoff weights for the motors. I think I have three or four ounces of rocket weight in addition to the engine. And if I'm skinning with white paper, I can avoid primer and hit it with a coat of the white epoxy paint and call her done. So, this will involve a lot less finishing weight than my usual rockets. I can also try lighter weight materials (posterboard, corrugated cardboard) in a pinch.

It's a good point about the perspective involved in the receding rocket. To my eye, the angle is such that the actual rocket would be longer/skinnier/pointer than the actual logo... it looks like it's a little bit tilted away from the viewer, based on the curvature of the line representing the separation between the rocket and the thrust. This is a very debatable point, and I will revel in the ambiguity and use it to my advantage in deciding how to construct the thing.

That said, I will print it out large and make some measurements so I can get fin proportions right. Do we all agree this is a three-fin rocket? To me, it looks like we're facing the middle of the section between two fins and the third fin would be pointing straight away from the viewer.

I may have some time to putter with this today... let's see where it goes.

Marc

 

[Marc_G]

I think it was Estes's idea of a Sprint surface to air missle...something I "seem" to remember.

https://www.designation-systems.net/dusrm/app4/sprint.html


Found it

OMG. Operational for a single day. Wow.

 

[JPVegh]

It could be three fins or four fins or no fins. Perhaps The "fins" are transitional pieces themselves and this is a finless design? Ain't perspective a B****!

 

[Saluki]

This rocket looks like the logo. https://www.semroc.com/Store/ProdImages/Starlight-lg.jpg

 

[Marc_G]

I spent an inordinate amount of time hacking foamcore board to bits. I did some comparisons and found that the foamcore I have is just a little bit (~25%) heavier than corrugated cardboard, but seems much stiffer, so I stuck with it.

Based on my measurements I mad a bunch of centering rings:



These were cut out with a circle cutter. I had an earlier idea where I would cut out squares, with a BT55 hole cut in the middle, and spin them around next to a disc/belt sander and buzz off the excess. Guess what, this doesn't work with foamcore board. Oops. I restarted using the circle cutter and got probably adequate though far from perfect cutouts.



Next I used a hobby knife to cut out the BT55 hole.

 

[Marc_G]

But how to align them perfectly? I started out spacing them per my original diagram.





It eventually occurred to me that I could lay the structure on the table and use the nose cone to set the angle. Not sure if you can see it in the above pic, but I was WAY OFF.





Looks like I had too big of an angle to start with, so I actually need fewer of the rings.

 

[Marc_G]

The movie in the background is "Some guy who kills people." I'm halfway into it; seems to be a heartwarming tale of a guy who was abused by neighborhood thugs, eventually went to a mental institution, and now is out and works at an ice cream parlor. His estranged daughter shows up, but meanwhile he's working to even the score with the thugs.

In another thread I mentioned that the Gorilla expanding glue was useful in my experience just for gluing stuff into nosecones, like noseweight. Well, I'm about to use it to glue these centering rings on. I think it will give the best bond between the body tube and the paper+foam in the foam core board.

That's where I think this build will sit for several weeks. I have a work meeting to travel to, and when I get back, I'll be getting ready for a vacation to the east coast. So I think I won't be building for a while, but will have to live vicariously through watching all of your builds. Thank goodness for smartphones.

Marc

 

[Marc_G]

I trimmed the body tube to size and glued on the discs with Gorilla Glue. It made a good strong bond; I'm glad I brought the glue out from the back of the shelf.

I've also got some ideas to mull over re: fin attachment; I'll eventually prototype some fins out of cardboard before cutting wood.

Meanwhile I have to find a large enough sheet of something like cardstock. Any suggestions for solid heavyeight paper that I'll find in a big enough sheet? 8.5x11" won't due for this... I need something like a roll that's pretty wide. I've heard someone mention construction paper. I will have to check into that. Any other suggestions? Maybe some sort of kids' art paper on a roll?

Anyway, it's off to my business trip now.

Marc

 

[Rocketbuilder]

How big does it need to be? If it's not too small, I say definitely go for a poster board.
What's the diameter of the ring a the bottom?

 

[Marc_G]

Around 4 inches. I forget which disc os the bottom one now as I discarded several after getting things lined up.

Just today I remembered I will need to put in a launch lug. Oops.

 

[Marc_G]

This build has sat on the bench for almost two months.

I finally got around tom oving it forward again. I decided to use cardstock for the outer cone but couldn't find a piece big enough. Instead I went with heavy weight construction paper. Not construction paper like kids use, but the paper you can buy usually near the paint section at the hardware store in big rolls. It's not as heavy as cardstock but it's pretty good stuff.

I laid the body tube/centering rings down on the paper and did a few test rolls, eventually deciding on how to roll it so that the paper comes to within an inch or two from the tip of the nose cone. I rolled it around and made some quick cuts with a sharp pair of scissors.

Here's a view of the pieces before putting them together:



You can also see a fin on there... I decided to create some slots to guide them in once the paper outer cone is on. This will promote getting them on in the right angle relative to the body tube.



I also made a rigid launch lug and put it in close to the body tube:

 

[Rocketbuilder]

Has it really been two months already? Wow, that was quick!
Anyway, I'm g;ad you got back to this one. I'm looking forward to the flight report.
Are you still planning on using 18mm motors?

 

[Marc_G]

On the bottom of the rocket, I made some marks to show where the fins would line up and attach:



In the above, you can also see I made some slits in the bottom part of the cone that will eventually fold over.

Next I made some cuts where the fins would go through. I sort of screwed up a bit, in that they weren't straight as I would like them, but they were serviceable enough.



Next, I put the fins in, with liberal coatings of Titebond Molding and Trim Glue to finish some double glue joints.



Eventually I folded over the slit paper on the bottom and finished up the basic attachment:

 

[Marc_G]

I'm still hopeful this will work on 18mm motors, but we'll have to see how the weight goes. I'm going to build it with a 24mm mount just to be sure.

In the last picture in the previous post, you can see some drip marks on the top of the paper part. This is thin CA I soaked into it, as there will be some sanding of fillers at the top where the paper and plastic mate up.

I then went over the paper/wood joints with TMTG fillets and let them dry overnight. Then I went in over the dry fillets with a second layer of TMTG. They are drying now.

The fins were shaped based on measurements I took from the logo (I printed out an enlarged version and measured it). The balsa fins were made from 1/8" stock that I sealed with CA after beveling them. I kept the CA off areas near where the glue joints would go.

 

[cwbullet]

Pretty neat build. I am interested to see how the first flight ends.

 

[closet astronaut]

I guess I caught this thread too late judging by the photos. I was going to say, Piece of cake build, JP's right on track with the cardstock and centering rings. As far as transitions go, here's the formula..



I recieved this from Mike Bauer, this is how I do it. Any way, looks like you got a handle on it, but maybe others who tune in here will find it usefull.

BTW..cool idea, looking great.

 

[Marc_G]

Thanks for the transition formula, CA! I'll use it in a future build where the transition might be too big to print using the online tools I've found.

Meanwhile, it occurred to me that the nose weight I was planning to stuff in the nose cone is still on my bench, and the rocket is all glued together. Oops. I can always coat some BBs or something in epoxy or gorilla glue and dump them in and let them adhere to the base of the nose cone.

I didn't mention it at the time, but I tied some 200 pound braided Kevlar to the nose cone eyelet before sealing the thing up. This will be used to anchor the rear ejection system, whose specific details I'm still working out. Basically, it will be a 24 mm D mount adapted out to something like a loose BT55 coupler. Had I planned sufficiently ahead, I could have built the thing out of BT56 tubing, and a BT55 coupler would have been perfectly loose inside to pop out with the ejection charge. As it is, BT55 couplers are too tight for the application. I will poke around my parts bin and see what I find, but I could always use BT50-55 centering rings, peel them down a bit then do a roll or two of cardstock.

Near the aft end of the motor mount, I'll put a BT55 to BT60 centering ring, which will serve as sort of a thrust ring to push the rocket up. Reading this, I'm not sure if it makes sense, but in my mind it all fits together. The key thing is that inside the main body tube, there will be nothing to inhibit pulling out the chute as the motor ejects, and yanks on the kevlar cord, eventually pulling out the chute (which needs to be protected somehow, perhaps by a bulkhead or something.

Marc

 

[Rocketbuilder]

I guess I caught this thread too late judging by the photos. I was going to say, Piece of cake build, JP's right on track with the cardstock and centering rings. As far as transitions go, here's the formula..

View attachment 95709

I recieved this from Mike Bauer, this is how I do it. Any way, looks like you got a handle on it, but maybe others who tune in here will find it usefull.

BTW..cool idea, looking great.

Read step 4 carefully. Someone was hungry when they wrote that! :roll:

 

[hcmbanjo]

Boy, for somebody who had:
"No idea how I'm gonna do it..."

It looks pretty good to me!

 

[Marc_G]

Read step 4 carefully. Someone was hungry when they wrote that! :roll:

Heh heh. I saw that typo, but didn't want to be the first to comment on it. :wink: I gave up being the spelling/grammar police long ago. But it gave me a smile when I read it, and I'm glad I'm not the only perfectionist out there... :grin:

 

[Mushtang]

I laughed at that too.

Also, I think step 5 describes the most difficult and inaccurate way to do that. Using a bit of trig to find the angle COB seems way easier to me.

 

[Marc_G]

I weighed the rocket prior to primer / paint and it was 138 grams, without the motor tube or parachute, which I haven't made yet. So, unless this thing is super stable, it's looking like C6 engines won't cut it.

Meanwhile, I used CWF in spots and made quite a mess of things. I should have coated all the paper in CA to toughen it. Lesson learned.





And here she is in primer (Rusto auto filler primer), with the can of white epoxy paint (hard enamel) I'll be using:

 

[Marc_G]

OK, about a week ago I painted her with that "epoxy paint" and let it sit in the garage for several days and downstairs in the basement (well ventilated) several days. The rocket still stinks a bit to me, but I have year-old enamel painted rockets that to me still stink.

I took it out and shot it. With a camera that is.




Tonight it gets some decals (just a few) and maybe some trim monokote, and tomorrow I'll give it a coat of Future.

Marc