Construction and assembly advice

What are some pros/cons on lightweight fiberglass vs cardboard airframes? Some of the Maddcow LWFG airframe kits look cool.
Do G10 fins require a different approach when glued? A good epoxy such as RocketPoxy needed for G10 fins and CR's?
Some of the PML kits interest me as well. Thanks

SgtCarter said:

What are some pros/cons on lightweight fiberglass vs cardboard airframes? Some of the Maddcow LWFG airframe kits look cool.
Do G10 fins require a different approach when glued? A good epoxy such as RocketPoxy needed for G10 fins and CR's?
Some of the PML kits interest me as well. Thanks

Click to expand...

Any epoxy will work. Just remember to sand before bonding

When I first dabbled with fancy-britches fiberglass tubes I just used 5 or 30 minute epoxy. Worked well enough but with the quantities I was using it is actually pretty expensive. I've since "graduated" to adhesives like Aeropoxy structural epoxy and USComposites laminating epoxy with various fillers or none at all depending on the application. As for the pros/cons of FG vs paper, the biggest pro for me is the durability of the rocket when NOT being flown! It doesn't get crushed in the truck, kids don't mess it up, fins don't break off.... The next pro is the joy I find in working with fiberglass and carbon fiber. I just like using it, like touching it, like looking at it. The next pro is the ease of doing a really nice paint job vs trying to get your paper tube all filled and smooth. Cons? Most likely your rocket will be grossly overbuilt. So what. You can use a small chute and even if the rocket lands on concrete it will probably be OK.
Pros for the paper/cardboard. Your glue is lots cheaper! Stuff is easy to cut. A wicked kitbash is easy to do and won't drain your wallet!
As for fiberglass preparation before bonding, check out the sticky in the high power rocket section about bonding composites...secrets...government...something or other
-Ken
Oh yeah, the sweet rocket in my avatar? NOT FIBERGLASS!

Thanks for the info.

+1 on the high power secret government sticky thread.

Working on prepping my Punisher for fin filets right now. Clean, sand, clean, new cloth, clean some more.

I kind of like both worlds. I like using LOC tubing and laminating a layer or two of glass over the tubes. This give great durability with the low cost and easy building that comes with paper tubing. My L2 cert rocket is 6 years old now and has over 25 flights from 1,100 ft demo flights at the TARC finals to a Mach 1.2 screamer to 9,559 ft on a Pro54 L935. It was built from LOC tubes with two layers of 6 oz. glass laminated on them and tip to tip on the 1/4" ply fins. It's my workhorse and test bed for my RC controlled chute which hasn't worked too well yet. It's taken a lot of abuse and held up amazingly well. It's on its third paint job.

Stepping on Soapbox
I build with cardboard, Titebond and wood whenever possible. That includes the majority of my high powered rockets, as well. IMO, rockets should be made of frangible materials, so that they minimize potential harm during a catastrophic event. I once saw a 14' minimum diameter carbon fiber/Kevlar rocket auger into the ground 7' that was pulled out by a wench attached to a Hummer. The rocket might as well have been using a steel pipe.
Overbuilding is a real problem as far as I'm concerned. Unless you're plans include supersonic or extreme altitude, cardboard and plywood works. Good engineering is easier and less expensive than overbuilding.