Tubing questions for a new guy

[B787_300]

So I am looking into scratch building a model that will preferably go supersonic. I was looking into some tubes and have the following questions.

1. Why does PML Quantum Tubing saw not for above Mach .85?
2. What happens to UN reinforced Quantum at Supersonic Speed?
3. What tube is relatively inexpensive that is Supersonic capable with no modification?
4. If reinforcement is required, how many layers of Fiberglass should do it?

Some more info
looking at Mach 1.2...
3in dia

 

[CarVac]

So I am looking into scratch building a model that will preferably go supersonic. I was looking into some tubes and have the following questions.

1. Why does PML Quantum Tubing saw not for above Mach .85?
2. What happens to UN reinforced Quantum at Supersonic Speed?
3. What tube is relatively inexpensive that is Supersonic capable with no modification?
4. If reinforcement is required, how many layers of Fiberglass should do it?

Some more info
looking at Mach 1.2...
3in dia

Quantum tube is flexible and not resistant to heat. If you go supersonic, depending on the design of your rocket it'll have oscillations which will rip the fins off or fold the airframe.

Blue Tube is probably your best bet for low supersonic at reasonable cost. Phenolic can do it, but it often needs reinforcement for landing (although not for flight).

1 layer of 6-ounce fiberglass would probably be sufficient for 3" phenolic. But again, Blue Tube is a good, durable solution at reasonable cost.

 

[Issus]

Bluetube is really easy to work with, just dont let it sit on an angle in hot or humid conditions or you end up with a bit of a banana. Store it flat or perfectly upright. This is from experience

 

[Coop]

How does the reformulation compare to the older stuff?


Later!

--Coop

 

[dave carver]

Full length coupler tube is avalible from many sellers, even a cardboard tube would handle the strain then without the mess of fiberglassing. I have a 4" rocket I'm putting together from 5 seperate pieces of short cardboard tubing cored with a 48" full length coupler I got from Giant Leap. That and 2 small bottles of Gorilla Glue. I'll be useing a discarded credit card to spread the glue on the phenolic coupler and wetting the inside of the cardboard tube, I should get full contact between the glue and both surfaces when the glue expands. Just glueing with common glue isn't enough, gaps and voids occure and the Gorilla Glues' expanding properties are much desired for this.

 

[cbrarick]

LOC tubing, and it won't bend. I've done better then that with my vulconate which was made with wood glue.
If you don't mind the spendy stuff, the obvious choices: carbon fiber (lightest) or G10

 

[fyrwrxz]

How does the reformulation compare to the older stuff?


Later!

--Coop

The 'new' formulation ('2.0') has better moisture resistance and still retains some resiliency without being too brittle. IIRC this was developed from a manufacturer's response to a contract from the Army Ordinance Depot for packaging/protecting some of the larger shells used in artillery.

 

[grouch]

I have a bit of 38mm blue tube that has a slight bend to it. I have been reluctant to use it because I am afraid of leaving it out in the sun. I will most likely use it on something less critical like a tube finned rocket. As Rick said, you can easily go above Mach with paper. My unimproved Nuke Pro went 1.4 although I hear that's about the limit kinda. I say kinda because it's generally the coupler that lets go not the tube proper. I will continue to fly paper past Mach for the simple reason I like building with it.


Sent from my iPhone using Rocketry Forum

 

[K'Tesh]

If you want to go small and light, Apogee sells the Aspire, which it claims can bust the sound barrier.

 

[B787_300]

So blue tube will work with no reinforcement? What is finishing blue tube like?


Sent from my iPod touch using Rocketry Forum

 

[Issus]

Yes, BT will go supersonic - its very thick walled! Treat bluetube like cardboard tubes as far as finishing goes. Fill the spirals, or not, then prime and paint

 

[DizWolf]

fill, prime, sand, paint

Same, with duplicolor metalcast primer/paint

without filler, it'll take 5-6 thick coats of primer to fill the spirals.

So far I haven't had warping issues. I store them inside my house vertical.

 

[B787_300]

anyone have experience with using PVC as body tubes?