interesting find

[r1dermon]

i got a parallel wound tube from my friend from home depot. my original plan was to glass the whole thing to get rid of the bump where the material ends. but i've since decided just to live with it. my question is, has anyone ever done this with a tube like this? i mean, i dont know what size it is, i havent measured, but it looks like maybe 3-4 inches ID. im thinking that im going to have difficulty finding a nosecone to fit it. thats basically my biggest problem. the tube itself weighs in at 3 1/2 lbs, hopefully i can keep it under 10lbs. i want to be able to launch it on I motors. my friend told me that if i can make it into a rocket that will fly he'll give me 100 bucks. so thats good incentive. thats like 3 flights. lol. im probably going to do some through the wall mounted fins, still deciding on the design. maybe loc ONYX style. i want it to be sturdy. also, what size parachute would you guys recommend for this. it's probably going to be a 38mm MMT, maybe i'll throw in a 54, but im not sure yet. tell me what you think. i dont want to attempt it if you guys think the tube will crumble. it seems quite sturdy. i've pressed both hands on each side to try and crush it, it barely even bends. just give me some insight

 

[rstaff3]

Sounds like it is on the heavy side, probably due to thick walls. This is a constant source of discussion. Some say its inefficient and you should throw it away. Some say use it and make sure you put a big enough mount in I personally use a lot of odd tubes.

Nocecone...you probably need to build one yourself. I just used a couple of 3.25" tubes for a testbed rocket for PVC motors. I didn't want to invest nice tubes/parts so these thick walled things worked fine. I found a plastic cap from one of those microRC cars fit the tube perfectly. The thick plastic end cap from one tube, a piece of scrap 24mm tubing (optional), and some canned foam and I got a descent cone. Of course you can turn your own from wood or foam. To me this is fun stuff.

You are way ahead of yourself on the chute. Design the rocket for the motors you want to use, weigh the parts, add the motor, then use a chute size estimator. Oh yeah..iterate by adding the chute weight to the rocket too.

 

[GL-P]

The problem I heard with such tubes is that they tend to have bad wravels (sp?).
IMHO, I'd glass the thing. It'll look better anyway.

I'd stick a 54mm in there and fly it on a Pro54 K185. (and maybe some outboards?) The K185 is slow enough to prevent some serious shredding but does have enough boost to get it up there.

I simmed a 4inch rocket at 150oz full with an AT K185. 5500ft and mach 0.6

 

[rstaff3]

If you think you'll ever use a 54mm motor then by all means put it in. But a J350 will get a heavy 3" rocket going pretty good.

 

[r1dermon]

the tube itself looks to be 6' tall, it is the remains of a roll of carpet. came from home depot. i was thinking of maybe filling that crease with epoxy to get it to lay flat, and then laying down some filler. i dont need the tube perfectly round, but i'd like it to be close. also, i dont have a lathe to make a nose cone from, i was thinking of just filling a coke bottle with foam, cutting off the bottom and then wrapping it in a couple layers of glass or carbon fiber. then scraping out the foam and filling it with any needed weight. right now, just the tube is pretty heavy. 3 1/2 lbs approximately. for my first, and yes, i DO mean FIRST scratch built rocket, i want it to be simple. very simple. oh....what thickness of plywood should i use for the centering rings, and do you guys recommend 2 or 3 centering rings? keep in mind, i hopefully will be flying this on full I motors and maybe a J when i get my L2.

 

[GL-P]

Sandman fo NC making?

I recommend 3 x 1/4 inch plywood centering rings if the max you'll fly with is a J.

IMHO you'll need a pretty high boost " I " for that rocket weight.

 

[rstaff3]

Carpet tubes are indeed heavy. I have never found any that are worth salvaging.

You don't need a lathe to turn a cone, but improvising is always fun. I can't believe you'd use carbon on a rocket made out of 'scrap' but to each their own.

As for CRs I'd use 3, 2 for sandwiching the TTW fins and one further up. I might consider a long motor tube to act like a stuffer and put the third ring at the top end. Maybe 3/16" rings. You could measure the inside and see if you luck out and can use stock rings., with maybe a skosh of sanding.

Maybe cut the tube and make a payload...

Maybe....too many options....

 

[r1dermon]

rstaff, i would, because its my first scratch built. and i'd like to cover all bases at once. i've never laid any carbon, i've glassed once, and it wasnt great. i've never made my own rocket, and with this one, it will allow me to aquire a ton of HPR techniques all on one rocket. plus, then i'll have a spare nose cone for that diameter. so when i make a clone of it using top of the line materials, i'll already have the NC. woohoo. plus, then a 54mm MMT would be sweet.

 

[rstaff3]

I'd become proficient at glassing before I spent the money on carbon. Coverng a coke bottle isn't where I'd try it.

Thicker rings won't hurt. I've used the Giant leap 3/16" on a J350 powered 4" rockets, with TTW fins and internal fillets.

BTW, the boost phase on a baby J isn't goint to be as much of an issue as coming down. Make sure you design the fins right and pick the proper chute.

 

[GL-P]

Yeah, I'd learn to glass then try CFing. When you look at the cost of CF compared to glass, you'll see why.

 

[hokkyokusei]

I use a lot of "found" tubes, but I draw the line at carpet tubes. I have used them for making "rocket carriers" though.

 

[Stymye]

I've drug many a carpet tube home untill I figured out that not everthing round with a hole thru it made the best rocket body.
it's still hard to pass a paper tube by.

I have found very few that wasn't either crooked, partialy delaminated or very heavy... I't would seem a shame to waste an expensive motor just to get it into the air when you could build something high performance from much better material.

learning to build ,light ,strong and efficient is a big part of the learning process for me.....

now I have found some odd tubes that did make great rocket material...so I'm always looking.

 

[GL-P]

I have found that saran wrap rolls are exactly 1.5inch I.D.!

 

[r1dermon]

yeah, but i like the look of CF, and im kindof a nut when it comes to good materials. if its not the best, its not for me. know what im saying? i like speed, i like flashy, i like strong. this is what my whole life is about. lol. i bought a LOC aura as my first MPR bird not because its easy to build. and not because its cheap. i bought it because it was advertised to hit close to sonic speeds without certification, and because it would go 4500 feet above the ground. lol. it is my addiction. not only that, but i almost bought a booster vision camera for it. now that would've been cool. every purchase i make is of the highest quality things. from fishing line(you'll never convince me to use anything less than 15lb test, even fighting large mouth Bass...northern large mouth bass, 5lb max) all the way to my hobbies. im into RC, i bought the absolute fastest car available at the time. its just something i do, i can't get away from it. and so i will use carbon fiber on the nose cone! lol. i dont care about economical. on the plus side, i love a really heavy rocket with a huge long burn motor that will stay low long enough for your brain to really rattle inside your skull. its the ultimate rush. in my opinion. thats why i love heavy rockets. but, i also love super high altitude rockets that bust mach 2, and that will be a future purchase. lol. you have to really know me to know my addiction with speed.

 

[rstaff3]

Originally posted by r1dermon
yeah, but i like the look of CF, and im kindof a nut when it comes to good materials. if its not the best, its not for me.

Then I wouldn't recommend the carpet tube. I'm not above using such a tube, but I wouldn't sink top dollar into other parts of the rocket.

The only thing cooler than carbon is a carbon/kevlar weave.

 

[Ryan S.]

Originally posted by r1dermon
yeah, but i like the look of CF, and im kindof a nut when it comes to good materials. if its not the best, its not for me. know what im saying?

Then why the heck are you using Carpet tube? Go buy some fiberglass tube if you are all for the best materials.

I dont know why looks matter, you are going to sand and fill the rocket and wont see the CF. To get that smooth finish you need to vacuum bag EVERYTHING. and then do lots of clear coating.

 

[hokkyokusei]

Got to agree with the last two posters. By all means use carpet tube and other odd bits to build your rockets. Alternatively, feel free to go the carbon fibre route. But really, to combine the two doesn't make much sense to me.

 

[r1dermon]

ryan S, you dont HAVE to vaccum bag everything. or even anything. its just a good method. but there are other methods that work just as good.

also, im short on dollars, im going for my lvl 1 next year and i want like 3 HPR birds. i also want say 5 more MPR kits, at least 1 from aerotech. so i mean, bt next season, i will have dropped probably close to 500 bucks on rockets alone, and that doesnt include AP. i want variation, i dont want to spend 200 bucks on one rocket, and then not be able to get another rocket because of budget limitations. know what i mean? its more of a learning experience that im looking for. plus, if i screw up on the TTW mounts(which i've never done before) then its a free tube, and i can always trash it. i want to combine all the elements of HPR rocket building techniques into one rocket, that way, i'll know how to do everything, and i would've wasted like 40 bucks worth of fabric, 15 bucks worth of epoxy, a couple bucks worth of plywood, and a couple bucks worth of tubing. and maybe 8 bucks worth of nylon for a chute. i'd probably strip it in the end, after all is said and done, save the fins the NC and the chute, and then i can get a custom made tube to fit the NC and i will already know by then how to lay carbon fiber. so it will go together a lot more smoothly.

 

[rstaff3]

Well dude, keep us posted on how it goes. Not how I'd proceed, but you certainly will learn something from the build.

 

[r1dermon]

this is definately a no go. i epoxied a fin to the tube and then stress tested it under its own weight. huge crinkle. totally messed up tube. but nice fin. took me an hour of hand sanding. arg. lol.

if i can get my bro's cam i will throw some pics up. its pretty funny.

 

[rstaff3]

Yea not surprising for a carpet tube. But you tried something, learned something, and still have the fin, things could be worse.

 

[wwattles]

I learned one yesterday by trial-and-error also. Counter-corkscrewed fins. Too hard for someone at my skill level. Couldn't get the angles precisely the same. But I learned something from it!

WW

(Also tried carpet tube in the past - wife was glad to see it leave the apartment. Still got a 12-foot long, 3" OD Mailing tube in the corner that may be more promising.)

 

[DynaSoar]

Originally posted by r1dermon
i got a parallel wound tube from my friend from home depot. my original plan was to glass the whole thing to get rid of the bump where the material ends. but i've since decided just to live with it. my question is, has anyone ever done this with a tube like this? i mean, i dont know what size it is, i havent measured, but it looks like maybe 3-4 inches ID. im thinking that im going to have difficulty finding a nosecone to fit it. thats basically my biggest problem. the tube itself weighs in at 3 1/2 lbs, hopefully i can keep it under 10lbs. i want to be able to launch it on I motors. my friend told me that if i can make it into a rocket that will fly he'll give me 100 bucks. so thats good incentive. thats like 3 flights. lol. im probably going to do some through the wall mounted fins, still deciding on the design. maybe loc ONYX style. i want it to be sturdy. also, what size parachute would you guys recommend for this. it's probably going to be a 38mm MMT, maybe i'll throw in a 54, but im not sure yet. tell me what you think. i dont want to attempt it if you guys think the tube will crumble. it seems quite sturdy. i've pressed both hands on each side to try and crush it, it barely even bends. just give me some insight

I had a phenolic tube that needed to be REAL strong (see the thread about rebuilding my Mirage). First I wrapped it with 5 layers of self-adhesive vinyl, then I pulled a length of heat shrink tubing over it and heated it. The seam in the vinyl is not visible. The tube is as strong as the quantum I would have used if it came in 1.5". You can get heat shrink tube in 4" and larger sizes. It takes paint just fine. If you use it, best put it on before cutting slots. The shrinking might bend the tube if it's already slotted. The vinyl I used probably added to the flxibility I needed, but probably didn't add much to the strength. The heat shrink seems to have done that plenty.