Centuri's Early Concept Rocket

I think I put a heavy coat of primer... kilz clogs the sand paper. will be sanding for a few days...

I received my RockSim 8 license yesterday and input my Phoenix project into it. I did as much as I could considering I have never used it before. The rocket came out pretty nice and it seems to be stable according to the software. I made two versions: one with an 18mm engine mount and one with a 24 mm EM. I used all the default setting to do the calculations and it seems that it needs at least a 5 delay before ejecting the chute. It calculated that with a C6-5 it could reach close to 400 ft with a velocity at deployment of 52-55 f/s. On a D12-5 reaches 686 ft with a deployment velocity of 31.55 f/s. All this with a 12" chute.

I would like to know if there is a way to input the real shape of the nose cone into the program: it has a flat tip and a rounded rectangle profile, not round. The main balsa body also has a rounded rectangle profile as well as the transitions (on the Sim I had to put an upper transition and a lower transition). Also, the rocket has two main wings and four winglets (?), two on each wing (check the attached pic for an idea of what I am addressing here). I could not find a way to put the winglets on the main fins. If anyone can help me with this please do, I want to improve my skills with this Sim (plus show off to my friends and cousins back home)...

Here is the rkt file with a 24mm EM. Please address anything that I did wrong and let me know how to fix it (if time permits...)

DITTO

Been following this thread from the dugout and I must say I am quite impressed in your endeavor to do the carving by hand as well as so many other hand-worked facets.
Not too many people do that anymore!! Kudos

Excellent build and nice documenting....

Still we must know of the motor you will use for its first flight!!

-Chris

I did the Launch Lugs yesterday: I mounted two LLs, one 1.5" and another .75", on a 1/16" thick pieces of balsa. I trimmed, sanded, and filled with green putty (just to experiment with). Today I glued them to what will become the bottom of the rocket.
Tomorrow I may glue the small fins to the main fins.

Tonight I also worked on the RockSim 18mm file. I found on the apogee website how to trick the software into adding the small fins to the main fins ( https://www.apogeerockets.com/education/downloads/Newsletter113.pdf). The 3D does not show the small fins but it takes it into account when calculating the CG and the CP. All I have left is to trick the software to get the rounded rectangle shape for the main balsa body and the flat tip for the nose cone. Can anyone help me here?

I am pretty proud of myself: I am learning to use the software pretty quick. It is fun.

Looking at what RockSim simulates, on the 18mm configuration a D3-5 takes it to 800 ft but velocity at deployment is 79 ft/sec. The C6-3 takes it to 400 ft and Vel at depl is 18.77 f/s. I have C6-5s and C6-3s so I guess that during my first flights it will be C6-3s. If I can get D10-5s that is pretty good since it takes it to over 740 ft and V@Depl is only 28.26 f/s.

Which one would you use with the 18 mm configuration?

24mm configuration figures comming soon...

Well, the D3 or D10 are both out, as they are both OOP. The C6-3 sounds good, or if you're brave, a D13-7 (or -4, depending on how draggy it is) would work.

reporting that with a D13-4 RockSim says it goes up to 761ft and velocity at deployment (V@D) is 6.74 f/s (I like this one very much).... with a D13-7 it goes 756ft and V@D is 79.74 f/s... I do not know but at that speed something can rip...

Yep - sounds like the D13-4 would be a good motor then

Great motor too - very loud, big flame.

The D13-4'S should make for a real nice "viewable" launch. Good choice for a first flight!
In time should you feel the need for a punchier hole shot, I think Scotty @ Just Rockets will be getting more AT D21-7's. Its about the only place I know, to get them anymore. I think that would be a cool flight as well.

Good Luck~~~~~~~~~~~~~~~~~~>>>====> Fly High

Originally posted by rosko_racer
here is the body with a coat of Kilz primer/sealer. It is drying in the garage as we speak. I guess that now I have to leave it alone until the smell goes away.

Click to expand...

This is the point to stop and make that mold .... : )

Beautiful work, BTW. Keep it up! And thanks for all the pics!

I have no clue how to do these, that could be my next project.
But on that subject, what I plan to do is to finish this rocket first. Then I am going down two roads: 1) carve another body out of balsa, this time with the NC attached the lower transition, then look into making molds; and 2) follow Sandman's idea on how to do the rocket body.

I played with the sim this morning an made a few adjustments to the MM. Looks like the sim predicts it will be stable. The fligt sim movie shows that it tends to go into the wind a little and that the optimum delay is around 4 seconds. I am posting a few screen shots of the sim for you to look and let me know your thoughts.
This pic also shows the rocket design attributes.

All simulations are with 18mm motors... will work later on a 24mm version.

This pic shows the components tree and a few shots of the 3D model. I doctored this pic with GIMP, highly recommended.

On this pic you can see the results of the flight simulations with different engines loaded. Looks like that a C6-3 or a D13-4 will work as first flight engines.

Before I glue the fins to the Body I took some pics of the fins to show that I sanded the leading edge of the fins into a tappered shape (I think that is how you say it...). I plan to keep the trailing edge square for looks. I do not know if leaving the trailing edge square may significantly affect its flight but I believe that there are some kits out there that does not call for sanding the edges.

Here is a pic with the fin subassembly put together but they are not glued to the body yet. To date I have not yet decided if I am going for an 18MM or 24MM engine. Will keep playing with RockSim and see.

Curiosity got me doing this: I put the original cover of the Centuri MRDM alongside the PowerPoint outline and a pic of the clone rocket (The Phoenix). The Phoenix looks close to the one on the cover.

Hhhmmmm, I am thinking about making a set of landing gears based on the F-18 or something close for The Phoenix. I'm going to use the next Michael's 40% coupon to get a 1/48th scale bird and take the landing gear from it. Not to glue it to the rocket but to make it so that if I put the rocket flat for display I can attach them to the rocket ...

Logo prototype... work in progresssssss...................

read subject

I was borred and wondered how the decals would look on the bird... I printed them on plain paper and taped them to the rocket. I also did it to see if they needed some adjustments... at least one does.

What color are you going to paint it? As I recall the picture on the handbook was black and white, but it really looked like it was red or orange. Also, you should bring it down to the June NARHAMS meeting so we can oooh and ahhh over it.

Originally posted by rokitflite
What color are you going to paint it? As I recall the picture on the handbook was black and white, but it really looked like it was red or orange. Also, you should bring it down to the June NARHAMS meeting so we can oooh and ahhh over it.

Click to expand...

I am thinking about a red, probably a burgundy, for the upper portion and a charcoal gray, probably lighter, for the lower portion. A dark gray color that will let the black lines of the decals to be noticed.

I would love to take it to the next NARHAMS meeting, the only problem is I have Guard duty that day and cannot garantee that I will be there on time. I'll take it with me to drill and see if I can make it to the meeting. I'll take advantage and show it to one of the Majors who is into HP rockets there.

Really KEWL looking model rosko!
Burgundy and greys for sure Can't wait to see it.
Humm! Looks like another downscale micro will need to be add to the to-do list

The burgundy/grey scheme is gorgeous, but I gotta tell you...it looks amazingly cool just in the primer color.

I've always wanted to see that bird "brought to life", and you've done an outstanding job with it. Kudos!

Originally posted by rosko_racer
I would love to take it to the next NARHAMS meeting, the only problem is I have Guard duty that day and cannot garantee that I will be there on time. I'll take it with me to drill and see if I can make it to the meeting. I'll take advantage and show it to one of the Majors who is into HP rockets there.

Click to expand...

YAY! Here's a dumb question... Have I met you before at any of the meetings? Also, how are you making the decals for this masterpiece? If you don't have access to an Alps maybe we can talk at the meeting and and you can print them on mine.

Wow ....

Beautiful work!

Originally posted by rokitflite
YAY! Here's a dumb question... Have I met you before at any of the meetings? Also, how are you making the decals for this masterpiece? If you don't have access to an Alps maybe we can talk at the meeting and you can print them on mine.

Click to expand...

The only dumb question is the one that is not asked. Rokitflite, I have not had the privilege of meeting you or your friends in person. I may be able to go to the July meeting because that first weekend is the 4th of July and usually I do not have NG drill, then again I may travel to Buffalo, NY to see my sister. Thanks for your generous offer of letting me print the decals on your printer. I have been looking for an ALPs printer but have not been able to win a bid on Ebay yet. I will definitely keep you in mind when it comes to that.

Went to Wal-Mart and bought the Krylon's Red and Burgundy (kind of deep red). They did not have anything close to a charcoal gray so I will be visiting Hobby Works in Laurel after work and see what they have. Now, my understanding is that the regular Krylon is acrylic, how well will Krylon mix with Testor's enamel, acrylic, or lacquer? My experience with plastic models is that enamel over acrylic does not work.

Today is sanding and priming this baby for painting.

For decals I am planning on experimenting with the Testor's custom decal system for inkjet printers. I bought two a couple of month ago when WalMart had them on clearance. It comes with one sheet of white and another of clear decal paper and a bonding spray. I any of you had a chance to experiment with this let me know your opinion....

.... on second thought, with such a gorgeous rocket I think I am going to get better quality decals printed elsewhere. Let me work on that this weekend and make the necessary PM contacts.

Guys, thank you very much for your comments. Ever since I started this project I've had positive comments and great tips from everyone. This thread will be a long one and will keep posting pictures for you to enjoy. I sleep, eat, and think about this rocket everyday, it almost interferes with my wedding plans... well, this one way to start training the future misses into accepting my rocketry "addiction".