Blue tube--few are using it

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Wildman Rocketry
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Kraken fins with BlueTube = many hours with a craft knife and razor saw. I did mine by scoring along the lines with the craft knife, deeper and deeper, then use the razor saw to widen the score and get deeper, when the saw seems to stop cutting, craft knife again, etc, until the saw gets through.
It aint as easy as LOC tubing, but its not quite as difficult as fiberglass. DONT use a dremel cut off disc. I tried that and due to cutting on a curve, on a curve, it skitters all over the place.
 
KenRico said:
Have one also, not fitting my Performance Rocketry nose cone, so need to use the Blue Tube in another project.

Any speculation on how did they cut the Kraken fins ? Having a tough time finding a good upscale project because of the size and shape of the LOC nosecone- shorter with the blunt, rounded tip.

Will have to get back on Stickershock23.com and look for some ideas.

Kenny
Click to expand...

I know how I did it on a 3", 4" and 6" Kraken's. I like using fine tooth blades, seems to help keep it from chipping and using a blade short enough it doesnt hit the back side of the tube

fincut.jpg
 
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Just got my parts pack in.... had a motor mount...but something is....different with the one they sent :)

8123083669_b54f282b00.jpg
 
I just looked and it seems the parts pack is off the website now. I was planning on adapting down to 29mm, building light, and just making the coupler a baffle and flying it on G reloads.

Now, I have other ideas, and a big grin. Been looking for an excuse to pick up some 54mm hardware.
 
Salvage-1 said:
wanna swap the 54mm mount for the 38mm one?
Click to expand...

Not sure which swap you're proposing :=) You may be suggesting that I build it with 45mm MMT, or you're offering your 38mm MMT for my 54 :=)

Ari.
 
offer is.... I has a 38mm MMT with centering rings, dont really need it at the moment, but, I could use a 54mm version, if you wish to swap yours for mine.
 
Worsaer said:
I think there are many Blue Tube builders out there, as has been mentioned, you might not know a rocket is Blue Tube unless the owner shares the info. I really like using it for custom work. For example, with my Lockheed Martin DAGR (below), Blue Tube made the curved fins possible, and have held up well. My 4" build (also below) likewise Blue Tube - I wanted something rugged without the hassle of glassing it.

View attachment 102052View attachment 102053View attachment 102054
Click to expand...

Wow! That Lockheed Martin Rocket is really cool! Would you mind posting a few more details on it?
 
Salvage-1 said:
offer is.... I has a 38mm MMT with centering rings, dont really need it at the moment, but, I could use a 54mm version, if you wish to swap yours for mine.
Click to expand...

Sure, that works. Where are you at?

Ari
 
Rob, your mailbox is full.

In any case, Barry at LOC is sending me the 3.9"/38mm rings--and I already have the right size MMT in my pile of parts. If you're ever this way though (I'm in the SF Bay Area), I'm happy to hand you the extra bits I have from this deal.

Ari.
 
Here are a couple of deployment tests. It's disconcerting how much BP it takes to separate these sections. I wonder if humidity affects BT's dimensional stability.

Ari.

[video=youtube;Gix9Ze3V_zE]https://www.youtube.com/watch?v=Gix9Ze3V_zE[/video]
 
I have had good results using the 2-3 grams suggested by the online calculators, and this was in the summer with moderately high humidity. Is the fit with your coupler overly tight? Regardless of the cause, you could ease separation by sanding down the coupler a bit.

Also, it looks like you have a fairly short shock cord. I had a problem with the main chute deploying at apogee until I lengthened the shock cord (longer one for the drogue section, about 15 feet) and added shear pins to the nose cone.

I've had no problems with my BT kit (ARR Basic Blues 4), and it's been very durable and flown well. Enjoy!
 
The fit seems very tight now. Yesterday it was very loose--I had to put tape on the couplers to prevent sections form sliding off under their own weight. This difference is what brings up the question about humidity.

The shock cord is shorter than is typical. Of course since I have no parachute, I don't have to worry about it tangling. The recovery is entirely by drag that the individual sections create. Longer shock cord makes it even harder to pull sections apart--the nosecone has to travel even farther to separate all the sections, and it loses momentum as it travels.

I do have a plug for the MMT. I describe it in the main build thread: https://www.rocketryforum.com/showt...ube-fin-breakapart-rocket&p=427231#post427231

Ari.
 
iter said:
The fit seems very tight now. Yesterday it was very loose--I had to put tape on the couplers to prevent sections form sliding off under their own weight. This difference is what brings up the question about humidity.
Click to expand...

Yes, that does sound like moisture-related changes: did you seal the tube with sanding sealer? I know that in the past blue tube had warping problems related to humidity, which is reportedly improved with "Bluetube 2.0". Is it possible you have the older tube?
 
Mine definitively says BLUE TUBE 2.0 on the inside.

I have applied no sealer to the tube so far. I wonder if there's any particular one that you recommend. Also, I wonder if the recommendation is to seal the inside of the tubes as well as the outside. It's now all but impossibe for me, on account of all the soot on the inside from testing.

Separately, I imagine I need to wait for dry weather before I seal the tube--otherwise I seal in the swollen shape--or is this unimportant.

Ari.
 
The folks at ARR recommend Cabot's sanding sealer, which I have used. Minwax is also recommended. I think that the term "sanding sealer" is used to refer to different types of products, so I would stick to one of these. I found the Cabot's to be kind of like painting with thinned honey. It soaks nicely into the tube.

If it's been unusually humid where you are, I would keep the tubes inside in AC for a few days before sealing. I've never heard of anyone sealing the inside of a tube, so don't worry about that.
 
Jim, I recall you have a jig for sanding body tubes in a lathe. I think I need something like that to "round out" my couplers.

Ari.
 
After I dry and seal the tubes per Sully's suggestion.

Ari.
 
iter said:
Jim, I recall you have a jig for sanding body tubes in a lathe. I think I need something like that to "round out" my couplers.

Ari.
Click to expand...

I must have missed this post. Actually, the automatic body tube sander was a joke. But, I don't see any reason I couldn't put a body tube on the lathe, as long as it was 33" long or less (the capacity of my lathe). And I do put couplers on my lathe all the time to sand them smooth after flooding them with CA. I've made several jigs/jam chucks/thingamabobs for mounting them.

https://www.rocketryforum.com/showt...ch-build-Hanna-amp-Nicole&p=361407#post361407

https://www.rocketryforum.com/showthread.php?37190-Upscale-3in-Vagabond-Build&p=346546#post346546

https://www.rocketryforum.com/showt...uild-upscale-Estes-Shadow&p=409937#post409937
 
I am planning on using the 5.5" stuff for my level 2 build next year.
 

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