Xyla Foxlin L2 certification kit.

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Super useful collection of thoughts, @JohnCoker , thanks!

Aside from the technical construction/strength issues, your point about using a strong tube to preserve the work done on paint jobs is an important one. I put a lot of effort into getting the paint on my DX3, and the buckled payload body tube (from using essentially a high explosive charge for the engine - an I566) was really a bummer. Either I had to re-glaze the spirals, reprime, and repaint the rather large 4" tube, or I had to spend significant time reinforcing the tube, sanding, priming, and repainting the place where the tube was slightly blemished. I did the latter. I still need to some other touchup but the checkerboard was a PITA and I would be sad to have to redo that.

Excellent article in Apogee's newsletter from a while back in which they compare paper, blue tube, and FWFG tubes. Authors claim that BT can handle about 5x the thrust of paper, and glass about 30 times the thrust of paper. It would be really interesting to have the data on FG sleeved paper tubes.
Here.

Earlier, I had asked here if BT was in the phenolic category. Apparently not: ARR claims advantages for BT over phenolic.

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My issues with cardboard tubing are:
  • easily dinged during storage and transport
  • sliding parts (couplers and the tubes the slide into) get worn quickly
  • BP residue can't be cleaned up easily
IMO, fiberglassing isn't necessary for in-flight stresses for MPR/L1-2 motors. However, if someone is going to put a large amount of work into a paint job, it's better to do it on a solid foundation.

I've moved almost entirely to phenolic (paper- or cloth-based). Fiberglass/carbon fiber tubing is great as well, but needs special tools to cut (diamond blades and ideally wet saws to control the dust). There are several varieties of phenolic to choose from.

MaterialProsCons
cardboard
  • inexpensive
  • cut with simple tools
  • not durable
  • breaks down with moisture
  • light spirals
phenolic
  • durable
  • need woodworking tools
  • heavy spirals
fiberglass/CF
  • most durable
  • no spirals
  • expensive
  • need special tools
  • dust is bad news

To get back to the OP: I think it's wonderful what Xyla is doing to popularize the sport and kudos to her for being a great spokesperson!
Paper tubing is a great way to get into the hobby and I've also recommended LOC rockets for L1 and L2 certification.
John, I stopped flying cardboard rockets years ago for all of the reasons you describe, preferring to use fiberglass components. I have a tendency to be very rough on my projects and sometimes even fiberglass does not survive!

However, since forming a strong bond with the crew from LOC/Precision, I have started looking at cardboard again. I will not fiberglass the components; if I want fiberglass, I will call Wildman. I wanted projects that I can fly east of the Mississippi to ‘reasonable’ altitudes and still have them survive.

What I have done is sleeve the ENTIRE airframe. This presents a problem that the stock nosecones will no longer fit. I addressed this by removing the shoulder and epoxying a “stiffy” in place of the plastic shoulder. I also seal the inside of the entire airframe and the OD of the 'stiffy' with epoxy. This allows me to fit the components and makes BP residue clean up a breeze. I also add a wrap of thin brass between the top coupler and the airframe in the payload to ensure that the nylon screws shear and not create an unwanted slot. It is a lot of work; I have done this just to prove to myself that it can be done. YMMV…..
 
John, I stopped flying cardboard rockets years ago for all of the reasons you describe, preferring to use fiberglass components. I have a tendency to be very rough on my projects and sometimes even fiberglass does not survive!

However, since forming a strong bond with the crew from LOC/Precision, I have started looking at cardboard again. I will not fiberglass the components; if I want fiberglass, I will call Wildman. I wanted projects that I can fly east of the Mississippi to ‘reasonable’ altitudes and still have them survive.

What I have done is sleeve the ENTIRE airframe. This presents a problem that the stock nosecones will no longer fit. I addressed this by removing the shoulder and epoxying a “stiffy” in place of the plastic shoulder. I also seal the inside of the entire airframe and the OD of the 'stiffy' with epoxy. This allows me to fit the components and makes BP residue clean up a breeze. I also add a wrap of thin brass between the top coupler and the airframe in the payload to ensure that the nylon screws shear and not create an unwanted slot. It is a lot of work; I have done this just to prove to myself that it can be done. YMMV…..
Do you have a build thread showing some of these modifications?

Sounds super interesting
 
I'm middle aged and I want to make all 3 of those things. Maybe even bring them to the same event. Haul the rocket and a kayak on the teardrops. Use the boat to retrieve the rocket. The 16 year old punk kid I was developed DIY ethos, might as well use them.

Bong would be the perfect venue. But bringing the canoe would almost certainly guarantee all dry landings. So, worth it…
 
The thing is that you need to actively work to invite people into the hobby and make them welcome when they arrive. Confidently saying that kids have no interest in anything but their phones is a great way to drive the interested kids away.
This was in the Radio Club of Tacoma newsletter but it applies here too. Credit to AA7MA.
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Earlier, I had asked here if BT was in the phenolic category. Apparently not: ARR claims advantages for BT over phenolic.
It is another type of paper phenolic tubing. I believe they're trying to distance themselves from PML phenolic, which many feel is too brittle.
I like Blue Tube, and use it a lot.
 
Actual
It is another type of paper phenolic tubing. I believe they're trying to distance themselves from PML phenolic, which many feel is too brittle.
I like Blue Tube, and use it a lot.
I'm pretty sure there's no phenolic resin in Blue Tube. It's vulcanized cellulose: https://en.wikipedia.org/wiki/Vulcanized_fibre

I have a length of 29mm BT and it has no smell of phenol at all (I kind of like that smell because it reminds me of vintage electronic equipment from before the days of fiberglass PCBs)

Vulcanized cellulose is also known as "fish paper" (and no, I have no idea why, because it sure doesn't smell like fish) and in denser grades can be extremely strong. I believe the coupler bulkheads in AT kits and the non-aluminum seal disks and various insulator parts in AT reloads are made of this stuff (only black) - if I got this wrong I apologize to all involved! Many years ago when my Dad (RIP) first saw one of these bulkheads, he handled it thoughtfully and said, "You know, this reminds me of the stuff they used to make practice grenade casings out of" (he meant the ones that actually explode but without frag, not inert ones)

However, I don't have anything concrete on what they did to make BT 2.0, besides what's on the ARR website. They may have added something to it, or just changed the spec., since they claim it's better in various ways.

Scott
 
I just bought a roll of 0.01" fish paper. I think that laminating 2 or 3 plys together will give me material for a super-strong centering ring for LPR and MPR rockets. I'll report back. BTW, the material color seems to naturally be blue-gray. You can buy white fish paper but it cost more.
 
Nice video as usual. However.......
For level 2, not sure about using super glue for the coupler, not sure it has enough sheer strength compared to epoxy. Also might want a high temperature epoxy on the motor retainer.
Having said that, it does seem to work in practice. After all, she did get it all back in one piece. Just seems a bit unconventional.
 
Nice video as usual. However.......
For level 2, not sure about using super glue for the coupler, not sure it has enough sheer strength compared to epoxy. Also might want a high temperature epoxy on the motor retainer.
Having said that, it does seem to work in practice. After all, she did get it all back in one piece. Just seems a bit unconventional.
Super glue definitely not, but wood glue would be fine. Wood glue and epoxy are both stronger than the wood/cardboard they are bonding.
 
Super glue definitely not, but wood glue would be fine. Wood glue and epoxy are both stronger than the wood/cardboard they are bonding.
even with it being fiberglassed? superglue is more than enough with her glassing the whole thing. Did you happen to watch all the way to the end with all the flights?
 
even with it being fiberglassed? superglue is more than enough with her glassing the whole thing. Did you happen to watch all the way to the end with all the flights?
That's a good point.... CA might be enough to hold things in place until the Fiberglass and Total Boat epoxy do their job of holding the airframe together.
 
I really like the coupler being forced against the front centering ring. That's a big structural failure point if you are not going to fiberglass the rocket. I'd be more worried about getting CA on the shock cord than epoxy though.

I'm not sure a motor (Especially DMS) could get the epoxy soft enough to actually remove the retainer during flight but high temperature epoxy is recommended. Cardboard is a pretty good insulator.

The only other thing I would have done different is I would attach the parachute much closer to the nose cone but the entire recovery system setup is really preference.

I'm curious how long it will take for these to start showing up at launches. I think it is going to be popular.
 
I really like the coupler being forced against the front centering ring. That's a big structural failure point if you are not going to fiberglass the rocket. I'd be more worried about getting CA on the shock cord than epoxy though.

I'm not sure a motor (Especially DMS) could get the epoxy soft enough to actually remove the retainer during flight but high temperature epoxy is recommended. Cardboard is a pretty good insulator.

The only other thing I would have done different is I would attach the parachute much closer to the nose cone but the entire recovery system setup is really preference.

I'm curious how long it will take for these to start showing up at launches. I think it is going to be popular.
If Xyla can get more younger folks involved with rocketry that would be a great boon to the hobby!
 
Nice video as usual. However.......
For level 2, not sure about using super glue for the coupler, not sure it has enough sheer strength compared to epoxy. Also might want a high temperature epoxy on the motor retainer.
Having said that, it does seem to work in practice. After all, she did get it all back in one piece. Just seems a bit unconventional.

With a layer of fiberglass over the tube, using CA on the coupler isn't at all a problem.

She does some things a little differently than I would, but they're just different - I think this is a solid build video and is a great guide for a beginner.

-Kevin
 
Doesn't look like the video is linked to on LOC's website. Hopefully they'll do that, as I think being able to view the instructions would be a good selling point.

I know I found the Bumblebee video valuable pre-purchase.

Hans.
 
even with it being fiberglassed? superglue is more than enough with her glassing the whole thing. Did you happen to watch all the way to the end with all the flights?
I mean, it worked. Not entirely convinced it was the best adhesive for that application though especially when she was already using epoxy elsewhere.
 
Not to be overly critical... but there was no surface prep for the structural epoxy outside of some light scuffing of the motor tube or did I miss something?
 
She did scuff the motor tube but I usually peel the entire first layer off.

I am really tempted to buy one for a backup for my IRIS since they went to 1/8 fins.
 
So the scuffing or pealing is to remove the smooth glassine surface. Some folks have, IIRC, advocated a wipe with water to do the same. Does that work here? Glassine is supercalendered (rolled between rollers more times and at higher pressures than regular paper calendered), and I suspect that a water wipe allows it to swell a bit. This should give the epoxy the ability to soak in a bit better. But is this enough?
 
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