PML QUANTUM AIRFRAME

[RPMyers]

I am thinking about getting a rocket with a PML Quantum aitframe. I have never worked with this product and would welcome any thoughts as to building and durability. Thanks

 

[Steve Shannon]

For the most part they are very durable and as long as you prepare them correctly before using epoxy they’re easy to work with. They’re great for an easy to finish sport flyer that’ll fly at less than Mach. If you want to fly faster than Mach then you’re going to need to reinforce the coupler or replace it with a g10 coupler because I’ve experienced airframe flexing that leads to snapping the phenolic coupler.

 

[H_Rocket]

What Steve said. It is an easy to use and easy to finish material. It's one great weakness is that it's brittle in extreme cold.

 

[rcktnut]

I love the Quantum tube, easy to finish and has held up very well on the 3 rockets I have built with it. One thing with it though, a perfect fitting coupler/nose cone/ piston if used at 50+ degrees F. will get tighter and tighter as the temperature drops below that.

 

[cls]

I found to get a good bond with epoxy on quantum tube, it's gotta be really scuffed up. like 80 grit scuffed. even then it's not a great bond, but it's plenty serviceable.

nearly all my poop pipe rockets with pistons have crashed. some folks like it, though.

 

[Handeman]

The only quantum tubing rocket I have is a PML Callisto I built in 2003. I made a mistake flying it in 20° F weather and the tube broke in the middle when it landed on the frozen ground. A coupler epoxied in made for an easy repair. The piston is worse for wear, but after 20 year, it's still my most flown rocket. Just a guestimate, +200 flights.

 

[manixFan]

The great thing about PML QT kits is they are easy to build if you follow the excellent instructions and the many FAQs they have on the website. Good epoxy is key, as is surface prep. I have switched over to Triple7 BP substitute, which leaves a lot less residue inside the tube and on the piston. Either way, you'll want to wipe out the inside of the airframe and the coupler portion of the piston to keep them clean and easy sliding. (Triple7 does require better containment than regular BP, but the piston design helps with that aspect of it. But as always, ground testing is always advised.

Of course the other big benefit of QT is how easy it is to finish. I've mentioned in several posts that my early success with PML QT rockets really got me hooked on HPR.

Tony

 

[Rocketclar]

I have several PML kits and even a couple of hybrids (part QT with piston and the other cardboard LOC). My L2 was with a PML Black Brant X. I like them! Agree with many comments above. I always talc my pistons before launch. I also drill small holes in the AF to make loading the piston easier. And I promptly clean out my tube after a launch so the piston will smoothly slide. Here's my latest, Andromeda (stretched to have 2 pistons) like my Eclipse.

 

[Voyager1]

My experience is similar to the comments above. I’ve built many QT models from PM. It’s a very easy to use material and great for many models. However, I no longer use it these days as I prefer FG airframes and components.

My main issue with QT is its thermal properties. I fly hybrids with long airframes. On some occasions the narrower 54mm airframes had bowed when on the pad in hot sunlight when waiting for launch due to differential heating. This had caused the rail guides to bind in the rail.