Yank Enterprises

[kgholloway]

I was talking to the owner of LOC-Precision over the weekend and he mentioned that he was considering buying some tooling from Yank Enterprises. It appears that Yank has gone "belly up" and is in the process of selling off their remaining assets. That's a real downer because I'd just gotten one of their kits, a 2" Sandhawk, and was extremely impressed with both the overall quality of the kit and the flexible phenolic tubing used in it.

Is anyone else out there using flexible phenolic tubing in kits? If so what are the kits like?

Ken Holloway, NAR #78336, L-1

 

[KermieD]

Man, that's a bummer! I agree wholeheartedly with your assessment of Yank's quality. The kits are so strong, you swear you almost don't need a recovery system.

I don't know of anyone else who uses flexible phenolic for kit construction, but I do believe Dave Urbanek sells tubes at https://www.rockymountainrocketry.com if you're looking for it. His prices aren't rock bottom, but they're reasonable, and his tolerances on ply centering rings rivals that of Aerotech's rings. I got CRs and a motor tube from him to make a 54 to 38mm motor adapter and he sent it to me basically assembled but not glued. I could barely get the CRs off of there. Get out the sandpaper!

 

[KenParker]

Phil, Craig - I'm expecting help from you guys. When Mark B finds out Yank is going under we'll have a major problem with the boy - Yank is one of his favorite vendors. I'm expecting Mark to have a cow.

Er... uh... sorry about that cow remark, Phil.....

 

[Milo]

Ken,

Are we talking intervention or consolation?

 

[MarkABrown]

Oh, woe is me...woe is me!

Seriously, I'm major bummed! I loved Yank's quality of construction. I bought a 2" Wraith for my daughter for Christmas last year and it is one of the coolest looking rockets in our fleet.

PML sells some of their kits using phenolic. Also, Giant Leap Rocketry sells flexible phenolic tubing.

 

[swimmer]

With the unavailability of motors maybe rocketeers are not buying rockets. Why invest when motors are so hard to get? Hopefully this isn't the tip of the iceberg. BP manufacturers will probably do ok but mid-power and up is suffering.

Swimmer

 

[swimmer]

Read the post from Joe Burger, AeroTech, on Rocketry Online General Discussion Forum (then get back here). Sounds like some good news for a change.

Swimmer

 

[KermieD]

www.wildhobbies.com/news/default.asp?cmd=view&articleid=810

The saddest part of this story is that LOC is planning on ditching the flexible phenolic tubing, which is one of the things that makes the Yank kits great. Are there any kit makers left out there that use the flexible phenolic anymore? This is great stuff as it doesn't require any reinforcement at all except for the most extreme of applications.

 

[Stones]

There's plenty of talk in the newsgroups about Yank and all the different opinions on paper vs. fp(flex phoen.). The chatter also mentions that PML tubes are "crunchy", almost too brittle. Any thoughts on this? The more I look for answers, the more questions that come up.

 

[Austin]

I use and like PML Phenolic...especially the glassed stuff...it is like concrete!!! Tough!

Glassed PML or Glassed Paper...both are really strong...can't go wrong with either.

Carl

 

[KermieD]

I have a 38/29 motor adapter made of PML phenolic and it's hard as a rock. I haven't put it to the kind of stress it would take to crack it, though, so I couldn't tell you about how brittle it is. The Yank birds are made of "flexible phenolic" though, which is a compromise layering layers of phenolic with Kraft. It does have some flex to it, but is MUCH stiffer and tougher than Kraft paper.

If you don't want to glass but you need something tough, use the flexible phenolic. You can still get tubes of it from www.rockymountainrocketry.com. Dave will be more than happy to toss out advice as well.

 

[PGerringer]

Speaking from experience here: The larger PML tubes (specifically 7.51) are very very brittle. Take a look:

https://www.cybergatetech.com/phpgraphy/?display=Rocketry/MegaNuk/img_2261.jpg

And that is only one example. The body tube cracked and I could peel the pieces off like the shell of a boiled egg. That is why I always glass the larger tubes with 2 wraps of 6 oz. If done right and both cloth and tube are saturated with epoxy then the tube is rock hard. Strangely enough, the larger couplers seem to not be made of the same material...

 

[Stymye]

I preferr the kraft ..more forgiving,
I cracked a phenolic mmt just from dropping it
I'm glad loc is continuing the product line
loc tubes seem to be pretty strong

stymye

 

[KermieD]

The flexible phenolic that Yank uses is very different from the PML version as it is *far* less brittle while retaining a significant amount of strength. It's fantastic stuff. Once I get my L2 and start scratchbuilding a few big projects I have in my head, I'll be doing so exclusively with flexible phenolic. Besides...oddly enough, a 48" tube of flex phenolic at Rocky Mountain is less expensive than an equivalent tube of the same size LOC tubing from Magnum. And ya don't have to glass it if you don't want to.

The only downside is really that it's a little heavier than a glassed Kraft tube, but I'm not an altitude junkie anyway (yet...wait till I get into dual deployment and I may change).

 

[Stones]

Hmmm....so is the PML "quantum" tube not a phenolic then? From what I'm reading, it's a plastic tube with a very smooth finish. This sounds good to me. Any thoughts?

 

[KenParker]

I think you'll find that people either love quantum tube, or hate it. I just haven't found anyone "middle of the road" on quantum tube. But then again, there are certainly tons of people out there I haven't talked to.

My *personal* opinion of quantum tube is that I really like it. Both of my PML kits, the AMRAAM 3 and the AMRAAM 4 have quantum tube. You can get a superb finish fairly easily with quantum tube. No seams !!!

It is VERY IMPORTANT to remember to rough up the tube with 60 or 80 grit sandpaper at any point, inside or out, that you are going to epoxy something to. The sandpaper breaks the slippery finish and gives a good rough surface for the epoxy to bond to.

You also have to remember, since quantum tube is a plastic (polymer, if you prefer), the tubing does tend to experience a significant expansion or contraction with temperature changes. You have to *carefully* check your parts fits (nosecone to body tube, coupler to body tube, internal ejection pistons, etc) before *Every* launch, and add or subtract masking tape as necessary to the joints. You're supposed to do this anyway, even for fiberglass or paper tube rockets, so I don't see this as any extra work. It's just proper launch prep.

I guess the best thing for you to do is get a kit that has quantum tubing, build it and see whether YOU like it or not.

My $.02 worth.
- Ken