Starship Avalon: build thread

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If you're trying to shorten it try "braiding" it. It involves just making a loop and pulling another loop through it and it can shorten the shock cord quite a bit. It's really simple; we used to do this with string as kids. Here's a video link https://bit.ly/2vSjsXE that demonstrates the technique. Fast forward to 2:12. Tim Van Milligan calls it "crocheting" but you can just use your fingers, it's really easy.
 
The crochet technique (kind of like a daisy-chain of slip knot loops that untie when you pull it) is also a good method for packing non-elastic kevlar cord, but not sure how well that would work for the flat elastic woven type of shock cord you are using.
 
If you're trying to shorten it try "braiding" it. It involves just making a loop and pulling another loop through it and it can shorten the shock cord quite a bit. It's really simple; we used to do this with string as kids. Here's a video link https://bit.ly/2vSjsXE that demonstrates the technique. Fast forward to 2:12. Tim Van Milligan calls it "crocheting" but you can just use your fingers, it's really easy.
I had heard of the technique but never watched the video. That is cool.

The crochet technique (kind of like a daisy-chain of slip knot loops that untie when you pull it) is also a good method for packing non-elastic kevlar cord, but not sure how well that would work for the flat elastic woven type of shock cord you are using.
I am tempted to experiment with it. I'll just take a piece of 1/8" elastic and see if it'll crochet like that and then come apart easily. If it seems to work, and if it doesn't take me all day to do it, I just might give it a try. It certainly would seem to (a) make it easier to get the cord into the BT, and (b) reduce the likelihood of the cord getting jammed up in there.

I'll have to experiment with both that *and* the over-under coiling. Good fun stuff to play with. :)
 
I had heard of the technique but never watched the video. That is cool.


I am tempted to experiment with it. I'll just take a piece of 1/8" elastic and see if it'll crochet like that and then come apart easily. If it seems to work, and if it doesn't take me all day to do it, I just might give it a try. It certainly would seem to (a) make it easier to get the cord into the BT, and (b) reduce the likelihood of the cord getting jammed up in there.

I'll have to experiment with both that *and* the over-under coiling. Good fun stuff to play with. :)


I seem to have the same 1/8" flame-resistant flat elastic you use. Did this in about 30 seconds using just fingers. Doing it LOOSELY like in the pic ensures no binding (and it shortens the cord faster). I've done two flights using this method and so far no problems.

IMG_0095.jpg
 
I seem to have the same 1/8" flame-resistant flat elastic you use. Did this in about 30 seconds using just fingers. Doing it LOOSELY like in the pic ensures no binding (and it shortens the cord faster). I've done two flights using this method and so far no problems.
View attachment 325728

OK, I am sold on giving that a try. It's amazing to look at that and think it's going to actually pull out. :)
 
Watched a few videos, figured out the basic techniques, and then practiced in my car at lunchtime today using a 12-ft piece of 1/8" elastic.
ImageUploadedByRocketry Forum1502995166.321596.jpg

After completely crocheting the cord a few times, I was able to do the whole thing in a bit over 3 minutes, which means that my ~4' shock cord on the Avalon should take me a minute or so.

Like!
 
Watched a few videos, figured out the basic techniques, and then practiced in my car at lunchtime today using a 12-ft piece of 1/8" elastic.
View attachment 325980

After completely crocheting the cord a few times, I was able to do the whole thing in a bit over 3 minutes, which means that my ~4' shock cord on the Avalon should take me a minute or so.

Like!

Now, tie a 10 oz weight to it and drop it out a 2nd story window (or otherwise) and see if it unravels correctly. If it knots up in the center or anywhere for that matter, you may have your loops too tight. OH...remember to hold the other end in your hand....:cyclops:
 
I did the "yank it apart" test, and it came apart very easily. It was not as tight as it may look in the picture. Although, the rough surface of the elastic definitely does create a bit of friction.

I'll keep practicing some more and work on getting consistently loose-but-not-too-loose knots. I think I'm almost there.
 
You can also baby powder the cord and it'll give it a little lubricity.
 
Got my best time down to 2 minutes for the 12' elastic, I think that's good enough, though I'm gonna keep practicing periodically just so I don't forget how to do it. I did try attaching a light weight to the end and it pulled the whole thing out easily. Looks like I get about 4:1 shortening of the cord from the crocheting, so I should end up with a (roughly) 1' bundle to stuff into the BT.
 
Fantastic result.

It's been a pleasuring watching the process.


Good idea! I always have BP in my rangebox, will do that.

*error* Momentary Acronym Overload */error*

Brief flash of you cheerfully dusting your chute with 4F..........
 
Congratulations on an excellent build. I really enjoyed reading through this blog.

Time to light the fuse.... :headbang:
 
Congrats on finishing a really cool design & unique build, and thanks for sharing as it's been a really fun read! Can't wait to see the flight report! :)
 
Sprint/Blackstar hybrid from your thread

Maybe. I like it but it's a very straightforward build. Needs more refinement. I have a few other ideas to monkey with. See you back in that thread. :)

or that Cylinder rocket!(2x29mm with a 1010 rail running through the middle!)

Nah, Joe built that one already and I'm a bit sore that the deployment scheme I had envisioned for that rocket totally would not work. Really sorta pulled the rug out from my enthusiasm for it. I like the idea of the rail running through the middle, though, you should definitely go build it. :)
 
Attention: this crazy monstrosity will fly on Saturday at the Rad Rocs launch, assuming I can get hold of a motor or three before then.

Looking forward to pics and/or videos!
 
I hope I do a better job with the cameras than last time. I'm gonna experiment with using 4K30 video on the launch and then seeing if I can get good image grabs from it. I'll experiment with that on some others' launches first to see if it works.

Definitely want some video to see the thing spin, but I don't want to miss out on some good launch images either. We'll see how it goes!
 
Attention: this crazy monstrosity will fly on Saturday at the Rad Rocs launch, assuming I can get hold of a motor or three before then.

The most anticipated launch since Apollo 11 ! :wink: What's this assuming noise ? 18mm BP, right ? Is there a shortage in The Garden State ?

Please make sure you arrange for multiple still and motion picture camera operators at the field. Outsource the operation of your own equipment so you can focus on flight and recovery operations.

GO! GO! GO!
 
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