LOC DoorKnob HED DD build

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Congratulations, Chris!

It's too bad about the switch, but it sounds like you got past that quickly for a successful flight. I'm looking forward to seeing this beast fly in person some day --- do you have plans for your next flight?

The paint job turned out nice too!
 
ChrisAttebery said:
I was able to get my L1 re-cert completed today. I had a problem getting the altimeter armed. Unfortunately it looks like my magnetic switch died this week. So, I took it out of the loop and used the twist and tape method to arm the altimeter. After that little fiasco everything else worked as planned. The flight was nice and straight and the rocket had a great whistle after the motor burned out. The RRC2+ beeped out 993', a little short of the 1133' that Open Rocket predicted. If I add a transition to the base of the rocket as Tim from Apogee suggested to use in RockSim for stubby rockets the simulation shows 959'.

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Well done, Chris.

Your bird looks like a Killer Bee!
 
I'm not sure. It worked fine last weekend. I'm going to redesign my tray so while I'm at it I'm going to design in a screw switch and guide tube for the screwdriver.

thobin said:
Congrats on the L1! So what happen to the mag switch? How long have you had it? I'm trying to wrap my head around what could have happened to it, was shorted out some how? Thats a bummer dude at least and best of all you still got you LVL 1. :)



TA
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The next flight will be at October Skies. I'll be using a 3 grain 54mm CTI. Right now I'm leaning towards the K360, just because it's the only K that fits that case. I will definitely be using the cable cutter and a drogue on that flight. It's projected to hit ~3500'.

The paint came out fairly well. I had an issue with paint soaking through the masking paper in a few spots but it looks fine from 20'. The paint is still soft after a week too.

ThirstyBarbarian said:
Congratulations, Chris!

It's too bad about the switch, but it sounds like you got past that quickly for a successful flight. I'm looking forward to seeing this beast fly in person some day --- do you have plans for your next flight?

The paint job turned out nice too!
Click to expand...
 
Congrats and thanks for documenting this one. I'm considering a Doorknob for my L2 cert flight; a big dumb "model" rocket is right up my alley, I think. Assuming I can pick one up somewhere in the next few months.
 
It's a fun kit to build and fly. I just ordered a CTI K360 for the L2 flight in October. That should be MORE fun. :D
 
I wasn't that happy with the altimeter tray or the way it was attached to the nose cone so I designed and machined these brackets. They will be attached to the NC bulkhead by the u-bolt for the recovery harness. I have a new tray designed and I will mill it out of 1/8" plywood this weekend.

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Here are the brackets mounted on the bulk plate.


ImageUploadedByRocketry Forum1410394270.023509.jpg


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You take no prisoners with this one, do you :=)

Ari.
 
I received the router bits yesterday so I cut out the new tray and switch arm out today. I used 1/8" ply for both pieces.

ImageUploadedByRocketry Forum1410566379.965202.jpg


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That looks robust enough for a screw switch! Did you get any feedback on the magnetic switch failure?
 
No I still haven't heard back from him. I may just make my own screw switch if I don't hear back from him soon. The arm lines up perfectly with one of the vent holes.


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Well, it's been over a month and I still haven't heard from Featherweight about my magnetic switch. I decided to just make a screw switch instead. It should be much more robust. I finished up the wiring harness so the altimeter bay is complete.

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I've been thinking about adding a camera to my rockets for a while now so today I ordered a Mobius HD camera and a printed mount from Landru.
 
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I received the Mobius camera and mount this weekend. I machined some aluminum backing plates so I could just screw the mount to the body tube. The plates have an arc that matches the ID of a 7.5" tube.

I got the mount painted and mounted on the rocket.

ImageUploadedByRocketry Forum1412560318.234226.jpg


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ChrisAttebery said:
I've been busy today. I woke up and got the recovery system assembled, built a 2 gram ejection charge, and re-installed the altimeter. I used 2x 3/8" making tape strips to hold the nose on. I took the rocket out back and tested the ejection charge to make sure it was strong enough. After that I applied the decals on the nose and masked and painted the second color on the booster section.
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Love the vacuum cleaner! Great idea!
 
Pretty clever. The only thing I've ever seen is using a vacuum pump.
 
My level 2 flight went off without a hitch yesterday. The K360 was a perfect motor for this kit. The onboard video from the Mobius came out great.

My wife strongly suggested that next time I use a Skidmark. Sure honey, no problem. :smile:

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[YOUTUBE]ahpt81EWN40[/YOUTUBE]
 
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It was an awesome flight, Chris! My friend Hanna took these.

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Chris -

Congrats on your L2!!!
Your project is beautifully built and was beautifully executed.
And absolutely yes, Skidmark for the next flight.
 
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Congratulations, Chris!

It was great to be able to see the rocket in person and witness the fantastic flight! The video turned out good too. I showed it to my wife, and she was very impressed, so maybe that will work in my favor when it's time for me to float the idea of my own Doorknob. You can really hear the whistle on the onboard video. Another interesting thing is you can see the rocket bounce after it hits the ground.

I'm pretty sure it's going to be unanimous --- Skidmark next!
 
Thanks guys. It was a great day.

Let me know if there's anything I can do to help you out with your next project. You need to bring your wife out to Snow Ranch. It's a little more picturesque. My wife could use some good company. ;^)
 

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