6" Tubefin level 3 build

[sugardaddy]

Good to see you back and posting again Danny. I'll be watching this thread. Good luck on your level 3.

Thanks Bill, I have been real busy with My regular day job and RocketsRus is taking a lot of my evening time. Add 5 rug rats running around here and that dosent leave me much forum time lately...lol
I do poke my head in here quite often, i just dont get to post very much.

Danny

 

[sugardaddy]

Cool build -- ring fins and tube fins are cool!

If you're worried about airframe stress, I'd say a long burn motor, like the M745, isn't your best option -- I'd go for a mid-range burn, instead.

A really hard hitting motor gives it a whack, but it's short lived. A long burn motor doesn't hit it as hard, but often the peak velocity is higher, which causes its own problems.

If you want a Gorilla motor in that same case, I think the M1355RT would be a better choice.

Have you run any sims, to see what your peak velocity will be with various motors in that case?

-Kevin

Thanks Kevin. I really like the smoke trail and reverse mushroom cloud that you get from the WC motors. It make for great launch photos. Thats the only reason i really want to stay with the White Cloud motors.
I really wanted to do the Bucket rocket for L3, but not having an altimeter thats accelerometer based kinda made me worried and i didnt want to go buy even more stuff. I still plan to build and fly one soon.

 

[sugardaddy]

Good luck Danny . You should fly it on the 19th in tampa . At least down in ft myers theres no water for you to land in lol .

Eric

I'm sendind the rocket to the body shop for a paint job on monday. I dont think it will be done before the Tampa launch. Plus its only right that i do my cert at my home field...lol
We do have a pretty long canal that runs the length of our field. Not many folks have hit it, but it will claim a rocket every now and then.

 

[cjl]

I think it was going close to Mach and still had another second or more burn to go

I bet you were a little worried before you launched yours.

Actually, I wasn't too worried on my first flight - the N2801 is a pretty tame motor, and it weighed a LOT on the pad. My question was more related to future flights - I have both an N4100 red and an O3400 imax that I'm considering putting into my Kraken, and the O would potentially break mach (the N wouldn't be far off either).

As for the rocket in this thread, I'd personally go with the long burn. With most rockets, I'd agree with Kevin that the short burn motor would potentially put the rocket under less stress, but tubefins have a huge amount of drag, and I'd bet that with a longburn, you'd hit top speed fairly early on (well before burnout). Plus, longburns look cool

 

[MartyAMC]

I'll be flying it on Feb 2.
I've always wondered how strong the fins were on a Kraken. I guess you found the limit. I feel pretty confident that these fins will hold. There is a lot of surface contact for the epoxy to grab on to.


Danny

Gttta love those tube fin cert fligthts. I built a 10" diameter Kraken I called Kraken-Up several years ago for my level 3 cert. Weighted 96 lbs with a M3000 on the pad. I agree with John you'll need to attach the tube fins to the centering rings where possible. I designed my motor mount with longitudinal supports for fin attachment on my Kraken. Even with my fins angled at the bottom I inserted a section of body tube to double the thickness because I was concered about damageon landing too.

Can't wait to see the pain job. Good luck with the flight.

 

[cjl]

I agree with John you'll need to attach the tube fins to the centering rings where possible.

I'll be the dissenting opinion here - my Kraken (7.5 inch, 87 pounds on the pad with an N2801) had the tubefins just surface mounted, and it didn't have the slightest problem with either the flight (admittedly, that was a relatively small N, but still...) or the landing (the tubefins plowed a couple of nice furrows into the Kansas farmland after landing, since the chute dragged it a bit). Admittedly, mine is all FWFG, but even so, I don't think this one needs any additional attachment strength unless sugardaddy plans to really push it with some aggressive motors. Probably the limiting factor here will be the delamination of the blue tube at the attachment point, but I doubt that will be a problem on a slow to moderate speed 75mm M motor. As I said before, those tubefins will cause a LOT of drag, so it shouldn't get moving all that fast.

(That having been said, I wouldn't stick an aggressive M such as the M2020 or M2245 imax in it without further reinforcement)

 

[Eric1]

Yo SugarDaddy
Good Luck with the cert flight!
I think tubers are cool!!

 

[sugardaddy]

Thanks for all the comments guys. I dont plan on flying this on anything larger than a 75/6000 motor. I finished up the sanding sealer tonight and i'll drop it off at the body shop. I cant wait to see what they'll do.

Danny

 

[cwbullet]

I can't wait to see how this flight goes. There are a lot of doubters. I think if you keep your thrust and velocity down that you will be fine.

 

[AHansom]

I hope I didn’t come off as a doubter because I mentioned my rockets crash. I don’t think a tube finned rocket has any less chance of certing level 3 than a regular finned rocket. They all come apart if pushed to hard. This project looks well built and it sounds like a reasonable sized motor choice. I’m looking forward congratulating sugardaddy in a few weeks.


Do you mean the paint job is going to be a surprise?

 

[AHansom]

I finished up the sanding sealer tonight and i'll drop it off at the body shop. I cant wait to see what they'll do.

Danny

Is the paint job going to be a surprise? That would be cool to just have a custom car painter go at it and have a grand unvailing on cert day.

 

[sugardaddy]

Is the paint job going to be a surprise? That would be cool to just have a custom car painter go at it and have a grand unvailing on cert day.

The paint job is a going to be a surprise. I know the colors they are going with, but thats it. Unfortunately, i need to have the rocket back a few days before launch day so i can prep it. ITs still going to be pretty suspenseful for me. All i know is they are going to use the Shop's colors and might incorporate the alien logo somewhere. Here is a pic of the shop to get an idea of color.

 

[chadrog]

I like the direction this is heading!

 

[sugardaddy]

I saw the alien on the building and the name of the business and i knew i had to go in there and show them my rocket. The owner said "your in the right place" just seconds after entering the building. They had never seen anything like that and he told me he "I have to paint it!". All the shop guys are coming to the launch now too. I'm hoping to make new rocketeers out of them....lol

Danny

 

[cwbullet]

Cool story, but if it were a close encounter would you need their services.

 

[sugardaddy]

I dont think of anyone as doubters. I thinks is good to talk about potential problems and solutions. Its one of the reasons i started this thread. I want to hear what others think of the design and also get feedback from people who have made something similar. Thanks for all the comments guys. I cant wait till launch day!!!

 

[sugardaddy]

Cool story, but if it were a close encounter would you need their services.

lol.. i guess it should be named To Close Encounters.

 

[JStitz]

Danny this really turned out nice! great work. and I LOVE that 6" conical cone, it makes it unique for a tube fin rocket.



John

 

[sugardaddy]

Thanks John,
I had another 6" nose cone to choose from. Its an elliptical. when i tried one on and then the other, it was very obvious which one belonged to the design.

Danny

 

[sugardaddy]

I got her back from the body shop on Friday. Here are a couple of pics a friend took for me. I am about 95% done with this build. I still need to add a couple of screws in each fin, bolt on the retainer, add the altimeters to the AV bay and rig it with recovery gear. I cant wait to see the reverse mushroom cloud under this baby!

 

[KenRico]

my daughter will love the paint scheme, purple and green like her Super Neon XL !

Kenny

 

[mcderek]

Excellent. If it flies as nice as it looks you will be very happy! Great job!

 

[Getmore]

Nice job on the rocket Danny I saw it at saterdays launch. Should go real go with a L3 motor in it good luck with your L3.

 

[iter]

Very very nice rocket! I wonder if you've flown it yet.

Ari.

 

[rocketgeek101]

That's a very nice looking rocket you've got there! Don't forget to post pics of the flight.

 

[chris m]

Digging up a old thread , did this fly ?.

 

[3stoogesrocketry]

Twice . Once for a cert three , then danny made a 5 grain red M20000 that energeticly disasembled the rocket from the nose cone back .

Eric

 

[chris m]

Thanks , M20000. Would do it

 

[AHansom]

Twice . Once for a cert three , then danny made a 5 grain red M20000 that energeticly disasembled the rocket from the nose cone back .

Eric

M20000?? if not a missprint that would be about a 1/2 second burn. To bad about the rocket.

 

[conman13]

that looks awesome...unlike most rockets the spirals look really cool under that paint!!