phenolic

[bachsta]

how does giant leap rocketry's phenolic comparo to pml's phenolic

 

[lalligood]

I don't think you're going to find any significant difference(s) between them except for maybe smaller seams/spirals in the GL phenolic.

 

[aksarben10]

I have used both versions, GL and PML, I have not found much if any difference. I usually go for the flexible stuff while phenolic is strong it is also very very fragile. The flexible stuff is not much better but it does flex alittle bit which can make a difference on a hard landing between broke and not broke.

Scott

 

[bachsta]

thanks for the info

 

[rstaff3]

I have never used PMLs phenolic, but have heard of people breaking it by knocking over a tube that was standing on its end. I've knocked GLs over and there was no damage.

 

[bachsta]

how does a fiberglass tube compare to phenolic?
also what's so great about carbon tubes

 

[lalligood]

Originally posted by bachsta
how does a fiberglass tube compare to phenolic?
also what's so great about carbon tubes

Fiberglass tubing (like what you get from Performance Rocketry) is fiberglass cloth covered in resin and formed to shape. Phenolic tubing is paper tubing injected with resin. Carbon tubing is just like fiberglass tubing except carbon fiber cloth is used, which is a lot stronger than fiberglass.

Hope that clears up the differences...

 

[bachsta]

so what are the wait differences and how much stronger is fiber glass than phenolic?

 

[edwardw]

If you go to www.rocketmaterials.com he has some axial compression tests on tubing. I'll sum it up here.

3" Hawk Mountain Filament wound fiberglass
Max Load 8900 LBF average

3" Phenolic Tube
Max Load 3290 LBF average

3" Paper Tube
Max Load 1078 LBF average

As you can see the strength increases as your tube gets more complex. As for wait differences...well it depends on how much your willing to shell out for shipping to get it to you Back on topic, they do get heavier from paper to filament wound. Each material has its own advantages and disadvantages. Paper is great if you are not going that fast - there is a thread with a LOC paper rocket on an M. Fiberglassing a rocket makes it tougher and more resilient to a little late deployment or getting banged around - but they aren't completely bullet-proof. Filament wound fiberglass is a very strong material. I've seen a couple come in ballistic and they were intact and flyable. Carbon fiber is great for strong and stiff light weight rockets. Also - carbon fiber inhibits transmitting a signal through the airframe. That can be good or bad. One guy at our club uses a falconry tracker and when he can pick up a signal when the drogue pops out. That is his way of knowing if he deployed his drogue.

Also - it depends a lot on your application what material you choose. If you want to go as fast as possible, carbon fiber is a pretty good material. If you want to toughen up a bird so it can become a frequent flier - a paper tube with a layer of fiberglass will last a long time.

Edward

 

[bachsta]

am i right to assume that carbon is the strongest and the lightest out of all of them?

 

[edwardw]

Carbon can be the strongest. Mainly it is very stiff. Composite materials are usually strongest when used in composite layup, ie Carbon plus fiberglass, fiberglass plus paper. The great thing is you can tailor the strength characteristics to your needs. Paper would probably be the lightest out of them all, but not the strongest. I know a guy who is getting carbon tubes to approach the weight of paper tubes, he is only a few grams per square foot off.

Edward

 

[aksarben10]

Carbon fiber is also the most expensive of all the choices. I wish I could afford it, so far I have not gotten into the composites much due to the costs.

There is a cost the benifit ratio with this stuff. The bigger the cost the stronger it is.

Scott

 

[bachsta]

how does red arrow hobbies phenolic do in comparison to giant leap's and pm's phenolic. which one is the most damage resistant and which does best at high speeds

 

[edwardw]

All the phenolic tubes are probably within 10% of each other as far as characteristics go. If you are going really fast I would suggest either a paper rocket with a layer of glass or phenolic rocket with a layer of glass.

Also - it might not be a bad idea to buy one of each and see what you like - that's what I did and found which tube has the properties I like. Then if you don't use the other tubes I'm sure some other rocketeer in your club could take them off of your hands.

Edward

 

[bachsta]

ill have to try that. ive already tried the pml so ill have to get a sample of red arrow and giant leap. i like pml bevause i just feels reely sterdy but its is pretty brittle

 

[lalligood]

For a really cool application of carbon fiber components (not just tubing), check out this page on PML's website:

https://www.publicmissiles.com/UltimateIo.htm

I also like to point to this story to show people out there why you shouldn't overbuild your rockets either...

 

[rstaff3]

Sweet, never seen that page before. Just found the stuff on their site. Now I'll say I want one but can't afford it!

 

[lalligood]

Originally posted by rstaff3
Sweet, never seen that page before. Just found the stuff on their site. Now I'll say I want one but can't afford it!

I know what you mean... If you look closely, you'll see that the fins & CRs are carbon fiber too. When is PML going to produce & sell those?!? Great proof of concept, huh?

 

[rstaff3]

Yeah, I noticed those were missing. They do sell the cloth so I guess you'd make them yourself. As for the price, I certainly expected the parts of be up there so it wasn't a shock. Cool nevertheless.

 

[bachsta]

yah i would definitely be interested in one if the decided to produce them

 

[aksarben10]

Originally posted by lalligood
For a really cool application of carbon fiber components (not just tubing), check out this page on PML's website:

https://www.publicmissiles.com/UltimateIo.htm

I also like to point to this story to show people out there why you shouldn't overbuild your rockets either...

I saw that rocket at LDRS in KS two it was really cool. Frank built it for the spot landing compitition that year. If I remember correctly it was only two wraps of carbonfiber and then the manderal was removed. When you held it you could squeeze it and the sides when in quite a bit but the first thing that got you was the weight, or lack of weight. That rocket was not made out of the stuff he sells on his site. That stuff is super heavy duty the UltimateIo was a one off to see what he could do.

Scott

 

[rstaff3]

He sells three versions of his tubes...you are saying the lightest is not what's on this site?

 

[aksarben10]

I did not know that he was selling the lightweight stuff. It appears that you are correct at the time that I saw the rocket Frank said it was an experiment.

Scott