gluing PML kits

I got my first PML kit recently. The piston is already in the dumpster outside. But this quantum tube is semi intriguing.

How do people glue it? More like fiberglass or more like wood?

What about gluing QT to wood, or even to fiberglass?

It's more like a plastic/composite than wood.
Rough it up. Gouge it. Use epoxy.

(It shrinks/brittles in the cold)

I have built a few and dumped the piston on a couple too. I have always used epoxy for all components. And like Nytrunner says, rough it up.

awesome, thanks guys

Well I'll be the rebellious one here and point that I kept the piston on my PML and I can't wait to try it out. So there.

I've built a dozen or so PML kits. I keep the piston but switch from quantum to phenolic.

Funkworks said:

Well I'll be the rebellious one here and point that I kept the piston on my PML and I can't wait to try it out. So there.

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+1 for gluing PML with Epoxy. Prep surfaces as you would any CF/FG materials.
+1 for flying PML with piston in place. It's just a different mechanism for deploying a chute.

Variety is the spice of life!

Funkworks said:

Well I'll be the rebellious one here and point that I kept the piston on my PML and I can't wait to try it out. So there.

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Same here! If you can't build a kit to specifications than you're not much of a builder!!

AfterBurners said:

Same here! If you can't build a kit to specifications than you're not much of a builder!!

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uh, i think most of us here can build a rocket according to its directions..

Don't use acetone on Quantum Tube. Not pretty. My most recent kit came with a separate warning in there not to use acetone, my other kit likely did and I just overlooked it.
I love building with and finishing Quantum Tube. I've yet to experience any of the negatives that always come up but my only flight with it ended as soon as it began when I had a Loki go Roman candle on me.

I haven't used QT in awhile. I would say definitely scuff the QT surface before using epoxy. The fiber glass tube people also scuff before using epoxy. I have a fear, perhaps unjustified, that epoxy can slide off QT under some circumstances. On some rockets I put metal screws through the QT into small wood blocks that were holding thrust-bearing structures/rings.

BTW I like pistons, too, but that might be a hot-button topic! Ignore this statement.

PML has some of the best directions in the business. Follow them and you’ll be fine. Until you have quite a bit of experience I would not recommend thinking you can do better by deviating from the factory instructions v

The best glue for PML kits is a bit of an odd one that I stumbled across... JB Weld Plastic Bonder (not plastic welder). It is specifically for fiberglass and plastics. It's tan 15 minute epoxy that claims it cures in 30 minutes (it does not) but let it sit overnight and it's ridiculously strong when building PML or any fiberglass kit. My first PML kit was the Mini BBX and the JB Weld Plastic Bonder holds up extremely well. Quantum is pretty easy to sand with 60 grit to make the glue bite. Ditch the piston in any kit. Quantum tube expands/retracts in hot/cold so it's useless and will cause problems.

Hell the Plastic Bonder will glue plastic to cardboard and still unbelievably strong.

Steve Shannon said:

PML has some of the best directions in the business. Follow them and you’ll be fine. Until you have quite a bit of experience I would not recommend thinking you can do better by deviating from the factory instructions v

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I agree, right up until they suggest added a deployment jamming system.

Probably works great for a couple flights, but some of us fly the same rocket dozens or even hundreds of times, and keeping the piston working cleanly across that duration seems like a fools errand.

aerostadt said:

BTW I like pistons, too, but that might be a hot-button topic! Ignore this statement.

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Heretic!

Actually not only do I like QT & Pistons. I also am fond of the CPR3K system. Works great for <3" rockets with a single altimeter, though I have modified one for dual altimeters.

H_Rocket said:

Heretic!

Actually not only do I like QT & Pistons. I also am fond of the CPR3K system. Works great for <3" rockets with a single altimeter, though I have modified one for dual altimeters.

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could you give a quickie/laymans description of the system?

The piston fits inside the body tube and chute goes on top. When the charge goes off it pushes the piston and laundry out of the rocket. Just check out PMLs website. They give a good explanation and even have a cut away picture of a rocket for reference.

sorry i meant CPR, i know what a piston is

HVArcas said:

sorry i meant CPR, i know what a piston is

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The CPR3K is their version of a dual deploy system. It stands for Close Proximity Recovery. Check their website for more details.

MikeyDSlagle said:

Don't use acetone on Quantum Tube. Not pretty. My most recent kit came with a separate warning in there not to use acetone, my other kit likely did and I just overlooked it.
I love building with and finishing Quantum Tube. I've yet to experience any of the negatives that always come up but my only flight with it ended as soon as it began when I had a Loki go Roman candle on me.

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Ah good times. Still have that video!