5.5" Nike Smoke

[Neil]

Well, I got a call from my mom the second morning of LDRS, saying that my rocket had come. I of course forgot all about that within 20 minutes as I decided that I should heed the saying "A ship in the harbor is safe, but that is not what ships are made for", and started prepping my 38MM minimum diameter Mach Buster 1 with an H148.... But, as we were driving home, listenting to the "harry potter and the prizoner of azkaban" tapes, I rememberd the rocket that was sitting in my basement... I suddenly got impatient to get home...

When I finally DID get home (12 hours after we set off....), Shannon (my dog. As most of you know, I am a dog person ) was very exited to see me... And then she needed a walk... So after a half hour of getting the dog to calm down, I got down to the basement, got out my knife and cut open the box... Inside was the pre-glassed tube, fiberglass nose cone, pre-shaped fins, and and 54MM motor mount tube of the 5.5" Nike Smoke. Of course, as soon as I opened it, the gears started turning...

The "how can I improve this kit" thought that chronically occurs whenever I get a new rocket came almost instantly.

There is no payload bay in this kit, if you build it stock... Thats the first thing I am going to change.

There is no motor retention to speak of in this kit. Thats the second thing I am going to change...

And all the other small misc stuff I am going to change because I feel like it. A pair of quarter-inch all-thread rods, going from the middle CR to the aft CR, with a nuts n bolts motor retention sytem on the aft end of the rods. This will just give it some extra strenth, cause I like extra strenth. I can afford a slightly heavier rocket much more easily than I can handle a motor casing falling out. Before you start telling me that its pointless and that I dont need two all-thread rods going through a 5" rocket, realize that I already know I would proabably be fine with no rods at all, and I am putting all-thread rods in there because I want all-thread rods in there.

Besides, I want my rocket to be able to survive the biggest, baddest motor I can cram into the backside of this thing. I wont go as far as tip to tip glassing, but I will be giving it some healthy-sized fillets outside, and expanding foam on the inside.

That reminds me.... Can I use the same plastic spoons for the fillets on this sucker as I did on my 4" rockets? Or do I need something bigger?

OK... Now to the electronics bay... I cant very well have anything in the nose, so I think I will put it about 12" above the fin slots. (thats still between the middle CR and the forward CR, BTW.). I have a rectangle marked out on the tube for it already, and I think I can cut it out with my Dremmel tool, once I am sure its a good idea. I also cut out a half-centering ring (I didnt want to bother with a whole one, cause I dont have the proper drill bits in to cut the inside out... ) to use to make sure the electronics cant slide out backwards. I am (or plan to) going to glue the whole thing together on the motor mount, then put the motor mount inside the tube, then put the fins on.


So, is this a good idea, or am I just being silly again?

No, I havent got any pics yet. Just look at KK's thread, its the same thing... hes got pictures of the parts.

 

[daveyfire]

Don't bother with the payload bay -- put an e-bay in between the fins and you'll be set. Also, be creative with the forward nose cone space -- you can put in a tracker, or use it as extra room for chutes (same end dual deploy anyone?). That's one of the reasons I love the Nike -- it's got a HUGE amount of space in the top end for anything!

With the mods, be sure and check CP/CG. The Nike is pretty close to 1 caliber of stability because it was designed that way, so make sure you don't violate those numbers.

You can use that same plastic spoon for fillets. Or you can cut a piece of wood/sheet metal/whatever into the desired radius and use that. Personally, I like the look of plastic spoon fillets on 5.5" rockets, because they are less noticeable, just as fillets should be. If you want extra assurance, put 2" wide strips of glass across the fillets (1" on the tube, 1" on the fins). That'll be overkill for most any 54mm motor in that rocket, but your fins aren't coming off!

Good luck, keep us posted, and put a K660 in it!

 

[Neil]

How exactly does same-end dual deploy work? The drouge on top, then a BP charge, then the main, then another charge between that?

I dont quite understand what you mean by not bothering with the payload bay... Do you mean not to put the little hatch that opens up for the altimeter/battery ETC, or do you mean to keep that, or what?

I want to fly this on a J370GG once I get a case for it, and maybe a K530 or a K670 in it... (can you tell I like green flame? )

Should I put that adjustable nose weight thing we were talking about in that other thread in this rocket? Or just some non-adjustable nose weight? Its pretty rough on the inside of the cone... Lots of bumps and ridges. Plenty for the epoxy to "grab".

This thing is worth every bit of the $240 I spent on it!!!

 

[BlueNinja]

Removable and adjustable, that way as davey said you cant violate the cg cp relationship.

 

[daveyfire]

Originally posted by Neil, with additional new comments
How exactly does same-end dual deploy work? The drouge on top, then a BP charge, then the main, then another charge between that?

Do a search! You'll find lots of good info

I dont quite understand what you mean by not bothering with the payload bay... Do you mean not to put the little hatch that opens up for the altimeter/battery ETC, or do you mean to keep that, or what?

Most definitely put in the little hatch for electronics -- how else are ya gonna put e-tronics in? I just advise against cutting the tube and installing a "traditional" payload section, simply because you'll make space awfully tight in the booster.

Should I put that adjustable nose weight thing we were talking about in that other thread in this rocket? Or just some non-adjustable nose weight? Its pretty rough on the inside of the cone... Lots of bumps and ridges. Plenty for the epoxy to "grab".

I'd recommend it. Cut the allthread shorter than the entire length of the nosecone, though, put a bulkhead in near the tip to hold back the nose weight, and put a tube down the center so you can put fun stuff inside (RocketHunter anyone?). Basically turn the nose cone into your payload section.

This thing is worth every bit of the $240 I spent on it!!!

We told you so.

 

[Neil]

You had me a little confused, thats all.

So its safe to cut fiberglassed tubing with a Dremmel tool, as long as I do it outside, wearing a mask and safety goggles?

The nose cone is a very tight fit... Ill proabably have to take the Dremmel tool to that, too.

But how could I have a main chute in the nose cone, with the electronics where they are? I would need to blow the nose cone off to get the drouge out, but then the nose cone would be flying around, and proabably rip the wires right out of it, making it tumble down on nothing but a short piece of tubular nylon.......

You got me REALLY confused now... this is my first rocket with electronics in the fincan, so bear with me....

 

[Ryan S.]

I saw the words "same end dual deployment" dont use an AARD, look what happened with Jerry's NIke this weekend, use the Tether.

 

[karatekicker271]

Im not planning on doing dual deployment anymore than i thought about it when I glued the aft centering ring onto the motor mount (dumbest rocket mistake of my life) I am going to do it single deployment on a 60" chute with no other mods (except the motor retention). I have been in Tennessee for the past 5 days so I am trying to catch up but for all of the fillets I do on my rocket, I use pop-sickle sticks and the excess I sand away. Neil, you might have to make your fin slots longer and wider, mine were really tight. I didnt need to use a dremel for that (accually when I tried it only made it worse) I just used my handy dandy hobby knife. My nose cone came really really tight too (it almost got stuck when I tried to put in in there for a photo opt.) Just take your time. Oh and also, the fiberglass isn't hard AT ALL to sand. It is a really tight weave and I sanded the whole rocket in about 45 minutes. I hope this helps!!

KK

 

[Neil]

Ryan....

Care to break that down into terms a 2 year old could understand? I dont know what you mean by a tether (is this a specific product, or a build techniqe or what?)....




Yea, I couldent even fit the fins in those slots... I guess I gotta sand em down a bit. I dont really want to use the hobby knife on it.... Last time I tried to do that with a hobby knife, I ended up sticking the knife several millemeters away from the Femoral Artery in my left leg... Not pretty.

Ill use sandpaper, thanx... Id rather spend an hour sanding it then put another hole in my leg....



I got thinking my evil thoughts again... I really should stop doing this.... Is it possible to fit some 38MM motor mounts in between a 54MM motor tube and the ID of a 5.5" tube? WIth a little sanding? It looks pretty close to me... Will it work? I would like to make this thing as capable as I can... A few extra motor mounts wouldent hurt, would it? Maybe 2 38MMs or something....

Would it fit?

 

[rocwizard]

38mm would only fit if you cut the centering rings into pieces adn glued the assembly together. Even then the aft end of the tube would probably have to be flared out a bit. adding in like 4 29mm mounts would be fit great. 4 I200Ws and a K700W that would be a sight! or 4 H268Rs and a K1275R That will haul pretty good.

 

[Ryan S.]

a tether is a small devise that attatches to the shockcord, when your main charge goes your drogue comes out but the tether holds the rest of the shockcord down so the main doesn come out. essentially it is a bar with a hook around it, the hook cant get off because there is a top. When your main is about to come out an ematch blows the top off and allows the hook to free itself and the main to come out.

they are ~$75

 

[daveyfire]

www.defyg.com sells the Tether.

What happened to Jerry's Nike last weekend? Enlighten those of us who don't live on the east coast, please!

As far as the nose cone fitting tightly, all of Andy's cones fit tight. I don't sand them -- instead, jam it into the end of the body tube as far as it will go. Let it sit a few days. Then push on it more. It should slide all the way in. Let it sit a few days. You're done, no sanding -- the noses are two-part molded, so they come out a little oval-shaped. Putting it in the tube fixes the problem.

HTH!

 

[Ryan S.]

Jerry flew the smoke on 3 6000 loads and the AARD released at Apogee. This was on Friday. They looked and finally found it on MOnday

 

[Neil]

Never thought of that... Lets see... Is it really oval? Cant quite tell. I can get the thing in the tube all the way, so should I just stick it in there and let it sit? 4 29MMs sounds good.... Doesent the LOC Magnum come with 2 29MM outboards with a central 54MM mount inside a 5" tube? G40 airstarts would be cool... Lets see.... 40X4 is... 160... Two Gs is an H, two Hs is an I... I160, more or less?

Ill have to find someplace to buy a few 29MM tubes...

That tether thing is a little expensive... I might get one later, but for now, I am not flying this thing too high, so I can just use main at apogee...

 

[Neil]

It says the Tether can be added without modifications to the rocket...


Another possibility for airstarts.... F25s... H100W, more or less, if you can just add up all the airstart motors and get a rough estimate of the power... Considering it would already be going fast from another motor...

Is it hard to airstart SU motors? What electronics does one use? A timer?

 

[AlexM]

Buy a Perfectflite timer from Commonwealth. If you feel comfortable using a breakwire, you can get one for $23. If you would like a G-Switch, it will cost around $40. Personally, I got the G-Switch version, but am using a breakwire for redundancy.

 

[Neil]

Im new to this dual deployment buisness... I have never done it before.... So....

I know what a Perfect Flight timer is (im not *THAT* stupid...)

But whats a G switch? Wild guess....: Does it notice when the rocket is slowing down and fire the airstarts?

And I have absolutely no clue what a break wire is.


I guess this is another money-consuming aspect of the hobby...

Dangit, this lawn needs to grow faster... I need more money... I guess I can kiss the semi-automatic .22 airgun idea goodbye....

 

[Ryan S.]

G switch: senses liftoff and begins countdown

BreaKwire: when broken countdown begins

 

[scm86]

get a bunch of good files, they will help tremendously with slots that are too small, or taking off those little drips of epoxy or errant fiberglass fibers etc. a half round file, double sided flat file and a rat tail will do most every thing you need. when they get clogged, just brush it off with a wire brush, and theres no grit to rub off like there is on sandpaper...

Originally posted by Neil
Ill use sandpaper, thanx... Id rather spend an hour sanding it then put another hole in my leg....

oh, and use a break wire, its harder to screw up IMHO...

Scott McNeely

 

[Neil]

Hm... My mom's got a ton of those things that she uses for soapstone carving... I might have to "borrow" some for a while...

 

[DPatell]

Allthread? Why Allthread?

In all seriousness, this rocket does not need it. You could load it up with a 2550 and 4 800's, but I have a good feeling you would never do that.

For what you will fly it on, 38mm centrals, maybe the occasional 54, and hobby motors in the outboards, it's beyond overkill...most of the time you can justify overkill, but the allthread is plain old illogical. A lot of weight in the rear, dead weight at that. Just use massive epoxy fillets and you will be okay.

I know you want to "practice your allthread implementation" but please listen to advice, it's not needed unless you're going to fly something insane.

Substitute in Fin tip to Fin tip glassing. That has a strengthening effect, less weight, and prevents fin breakage.

 

[karatekicker271]

Neil, just listen to the people who know more about it than you do. It is just going to add more and more weight, making it harder to get up on the motors you want it on. Like DPatell and ryan said, its gonna add weight, and just listen to people who know more about it than you do. I am not saying I know more about rocekts than you do, but they do. Do your althread test on a rocket that is not as expensive, and you didnt work so hard to buy.

 

[Neil]

Fine fine fine... But then ill need a new motor retention system... The all-thread was going to have some hex nuts and a washer for motor retention... I guess ill just see if I cant find some extra bolts somewhere....

But the all-thread was only going to go halfway up the MMT, and only two rods, so actually I think tip to tip glassing might actually weigh more....

 

[Ryan S.]

no it wont. The allthread will still weigh more and wont give you as much strength

 

[Neil]

Two 10" long pieces of all-thread weighs more than tip to tip glassing with 6 OZ glass? THat doesent compute, but seing as I am not using all-thread, it dont matter. (you got me confused again... How much WOULD tip to tip glassing add? )

What weight 'glass should I use? is 6 OZ too hard to finish? Ive got a lot of that lying around, and not much else...

 

[DPatell]

Exactly, 10" of allthread, it's not much allthread, and in turn won't do much.

The tip to tip serves a better purpose, overall strengthening to prevent shreds and landing damage. It also ties everything together better than allthread ever will.

 

[Neil]

So I just cut out the glass to go just over the edges of the fins, then coat the fins and bit of the tube with epoxy, lay the glass on, wait for it to dry, then do it again?

And what weight glass should I use?

 

[DPatell]

yepp, use whatever weight you want, 6oz will work, then when you're done paint over it with another layer of plain resin to fill the weave

 

[daveyfire]

Originally posted by DPatell
yepp, use whatever weight you want, 6oz will work, then when you're done paint over it with another layer of plain resin to fill the weave

Aggh *bangs head against desk* not again!

Everyone repeat after me:

Resin is not a filler.

Resin is not a filler.

Resin is not a filler.

Good. Now that we have that out of the way, we need to know why. Resin by itself is incredibly *brittle*. Prove it to yourself by popping the resin out of the mixing cup after it cures and snapping it in half. It's incredibly strong when properly reinforced using a laminate (fiberglass, for example -- try breaking a piece of wetted out cloth in half!), but on its own it will crack and chip off and your rocket will look like a serious case of acne cleverly masked with cake frosting and band-aids. You also can't sand resin, because it is designed as a structural material. It's incredibly hard to sand, and I personally don't like putting any more work into sanding than I have to.

What you need to fill the weave is either a high build primer (Kilz, Smooth Prime, DupliColor -- Krylon isn't enough) or fairing filler to add to the fiberglass. West System's fairing filler is 407, the purple stuff. Mix this up with your epoxy so it's really thick and squeegee it into the weave. The filler not only makes it easy to spread and easy to sand, it also makes the epoxy much less brittle. I personally use the high build primer route -- 3 coats of UV Smooth Prime over a layer of open weave 6 oz (read: big weave) makes a glass smooth finish. Kilz also works, though not quite as efficiently. Smooth Prime sounds expensive, but one $40 quart can lasted me five years and several large rockets. I've burned up more in motors in those rockets (and I had more in parts in them) than that. It fills incredibly well and when it sands off, you can see the particles rolling off the surface (it's incredibly free sanding, and when wet-sanded, you rocket is dipped in glass!).

Repeat after me one more time:

Resin is not a filler.

This concludes your public service announcement. Now back to your regularly scheduled programming.

 

[DPatell]

Resin is a filler in my world, and it works great. It's a lot easier than anything else I've done, and it's good at filling only the weave and nothing else. Also requires less sanding. Sure it weighs a little bit more, but I never had luck with the fillers when spreading the epoxy over a large surface. It separates and gets all weird.

Works for me, and my rockets fly good in my book...ask my Magnum that got dragged a few hundred feet through dried dirt and corn stalk stubs, no chips in the resin, even on the leading edge of the tube that acted like a tiller...

And no damage when it landed hard without a main chute...from over 3,000'...

Here is a pic by our own LMazza