Breakaway 2.6" upscale build: The Castaway

[iter]

Two things happened recently. One, my 3 year old daughter and I built an Odd'l Breakaway rocket and had lots of fun chasing it around the park. Two, a club member was getting out of the hobby and giving away bits and pieces. I picked up what may have originally been a LOC Graduator but is now significantly shorter.

The natural confluence of these events is an upscale Breakaway, which I call the Castaway on account of its history as it is written (Ecc 3:5): "a time to cast away rockets, and a time to recover rockets." The airframe's condition means that if breakaway recovery fails to "dramatically reduce the vertical descent rate," my emotional investment in the experiment is lower than with a completely new build.

Our first step tonight is to square up the top of the fin can. Leah took quite the interest in the hacksaw and sandpaper!

Ari.

 

[iter]

BTW, the C-size Breakaway came from JonRocket.com. Roger Smith's YouBee is an inspiration for the upscale. Roger owns JonRocket.

The receipt for the Breakaway came with Bracha's neat handwritten שלום on it :=)

Ari.

 

[jadebox]

Actually, Bracha owns JonRocket.com. I just help where I can.

I'm looking forward to following your progress. This thread might even get Bracha interested in visiting TRF!

-- Roger

 

[iter]

Thank you for your encouragement Roger. While I have you here, maybe you know. On first launch of the Breakaway, we lost the nosecone and the first fuselage section. I confidently pulled out my box of spares, sat Leah on my knee and cut a section of 24mm tube. Then I discovered that the rocket is wider than 24mm--the couples are 24mm tubes and the fuselage is wider. So my spare nosecone wouldn't fit, my new BT section wouldn't fit, etc. I ended up putting a 24mm nosecone into the top-most coupler--you can see in the launch photo that the top (red) section is missing. I wonder where I can get a replacement 26mm (?) nosecone and body tube.

Ari.

 

[jadebox]

Thank you for your encouragement Roger. While I have you here, maybe you know. On first launch of the Breakaway, we lost the nosecone and the first fuselage section. I confidently pulled out my box of spares, sat Leah on my knee and cut a section of 24mm tube. Then I discovered that the rocket is wider than 24mm--the couples are 24mm tubes and the fuselage is wider. So my spare nosecone wouldn't fit, my new BT section wouldn't fit, etc. I ended up putting a 24mm nosecone into the top-most coupler--you can see in the launch photo that the top (red) section is missing. I wonder where I can get a replacement 26mm (?) nosecone and body tube.

Chris, of Odd'l Rockets, generally uses body tubes that aren't the same size as standard Estes tubes. This is because the tubes are a little thicker and stronger than the Estes-type tubes. I'm not sure which tube and nose cone the Breakaway uses.

I'm sure Chris would have offered to help, but I have a Breakaway kit that is missing the fins (since I used them to help design my upscale), so I'll send you a replacement tube and nose cone.

-- Roger

 

[iter]

This is very generous of you Roger! Have Bracha watch this space for Leah's gratitude when she finds out!

I need to buy 2.6" tube and couplers for this project, and I'd love to get some from you, but I only see the thin Estes tubes on jonrocket.com. Do you guys carry the thicker LOC-type tubes?

Ari.

 

[JPVegh]

Oh my goodness!! Your little girl is adorable!!! It's great to see a rocketeer sharing his hobby with his daughter. My daughter turned 32 this year and I really wish I had introduced her to rocketry when she was young. Good for you!!!

 

[jadebox]

This is very generous of you Roger! Have Bracha watch this space for Leah's gratitude when she finds out!

Will do.

I need to buy 2.6" tube and couplers for this project, and I'd love to get some from you, but I only see the thin Estes tubes on jonrocket.com. Do you guys carry the thicker LOC-type tubes?

No, we currently sell only the Estes-style of tubes. The LOC tubes are available from several vendors. I had to buy some to rebuild the "YouBee," but I don't recall where I purchased them.

-- Roger

 

[iter]

We have the tubes on order. Today we're working on the nosecone.

Ari.

 

[iter]

Thank you for the Breakaway kit and the body tube Roger! JonRocket stickers are especially big hit with Leah, and she applies both of them to the nosecone.

[video=youtube;AEreQt8Mgp8]https://www.youtube.com/watch?v=AEreQt8Mgp8&feature=youtu.be[/video]

There's a place a couple of miles form my house where you can use all kinds of woodworking tools for $80/month: https://sawdustshop.com. Today Leah and I go there to cut the body tube there into 5.5" sections. This is Leah's second visit there. First time around we use their laser cutter to make cardboard centering rings for a paper-cup oddroc. I go there alone, I spend hours there. Today, we're out in under 7 minutes. I'm teaching Leah about building things. She's teaching me about focus :=)

Ari.

 

[iter]

We paint BT sections using paper cups as stands. The finish comes out short of my expectations, but Leah says (I wonder if she's simply trying to please me), "Well, like them that way." So I leave the finish alone.



We test-fit a couple to each section.



And now we can mock up the entire rocket.



We make attachment points for the shock cord by cutting up some old C motors.



We sand flat spots into the empty cores to aid adhesion.



Surprisingly for me, Leah likes sanding more than any of the other jobs on this build.

Ari.

 

[iter]

We use JB Weld to attach the cores inside couplers. I wonder about adding a second set of shock cord attachment points diametrically opposite these one and running a second shock cord for redundancy--and for a straighter pull at ejection.

Ari.

 

[iter]

The separation works reliably when I test it in my living room by holding the rocket horizontally by the nosecone and thrusting the whole thing forward and then yanking the nosecone back.

But when I show the Castaway at the club meeting today, the single-handed "deployment" fails. I ask a club member to help, and between his yanking on the fincan and my yanking on the nosecone, 3 of the 5 shock cord attachment points fail. I recall similar failures with the C-size Breakaway. As with the smaller rocket, I need to reinforce these attachment points.

Embarrassing as it is at a club meeting, I'm happy that this failure occurs on the ground rather than in flight.

Ari.

 

[iter]

Successful maiden today on F27 SU motor. Beautiful deployment and safe recovery.

[video=youtube;tSopdubYFOs]https://www.youtube.com/watch?v=tSopdubYFOs[/video]

Don't know how well you can see the "wacky wiggler" action in the video--it does exactly what the original does, and recovers flat with no parachute and no damage. No baffles, no wadding, no prep. I like it!

Ari.

 

[iter]

I should add that after the attachment-point failures, and before today's flight, I add a second Kevlar line, a second set of attachment points and larger fillets. The shock cord is fully redundant through the length of the rocket.

Ari.

 

[loopy]

Very nice! That's really cool!

 

[iter]

Castaway, on its third flight at October Skies on a CTI G80 skid. Photos courtesy of Martin Hall. Sadly, no photos of the down part.

Ari.

 

[isobig]

Nice build and flights. What's the oscilliscope for? You into advanced electronics?

 

[iter]

Depends on your definition of "advanced" I guess. I make things like this for a living: https://www.kickstarter.com/projects/ari-krupnik/etcher-etch-a-sketch-for-ipad

Ari.

 

[isobig]

Cool!

 

[iter]

Onboard video from today's flight, includes view of breakaway deployment.

[video=youtube_share;9v0hCGN5hk8]https://youtu.be/9v0hCGN5hk8[/video]

 

[iter]

We're building a 4" version: https://www.rocketryforum.com/showthread.php?44149-Tubularity-4-quot-tube-fin-breakapart-rocket

Ari.

 

[iter]

Another flight today, this time at Moffett. Concrete is hard on paper and paint.

This is the first time I'm noticing it--apparently, in the apogee shot, you can see the part of the ejection charge going out through the nozzle.

Note F-18 and Moffett control tower in last shot.

Ari.

 

[iter]

Packing to go to Snow Ranch yesterday.

Ari.

 

[iter]

Thank you Jim (qquake2k) for excellent video and stills from SARG yesterday!

The motor is G106, a 29mm sparky.

Ari.

[video=youtube;5Zv1DSTPFjw]https://www.youtube.com/watch?v=5Zv1DSTPFjw[/video]

 

[cwbullet]

Great photo of the break apart recovery system. You have proven it works on mid/ high power. How long are your couplers?

 

[iter]

I have about 1.5"of coupler sticking out of each section except the fin can, which has about 2" sticking out.

Ari.

 

[iter]

Night launch on H123SK at TCC Dairy Aire. Same motor as in the previous post, but 4 grains instead of 3. Thank you Jack G. for lending me the case!

No photos of recovery, but what we did is tie 4 glow sticks between the sections. Worked out pretty well. The winds were quite strong and the rocket landed about 3/4 mile downwind but we had an easy time finding it.

Ari.

 

[iter]

This rocket is a year old now. Here's a flight from earlier today, including a recovery sequence (click for larger versions).

Ari.