Derek's Level 2 Build

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Aquaman33
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Re: Derek's Level 2 Build

Postby Aquaman33 » Thu Jun 25, 2020 11:53 am

My current plan is to have electronic deployment via a Co-Pilot 2 in the nose cone. This will be backed up by motor deployment a few seconds later.

So I designed an altimeter bay that fits inside the nose cone.

Image

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I printed it on its side with very thick walls, so that its as strong as possible over the long dimension. I tried to snap an early prototype and was unable to break it with my hands. So that's my unscientific way of testing that its strong enough.

I have been playing around with tree supports for the first time. They produce some interesting results.

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Co-Pilot and switch on one side.

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Altimeter Three on the back, with access holes to buttons, battery mount screw and the LED.

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When fully assemble it will be mounted on a carbon/plywood disc with the U-bolt securing the 2 pieces together.

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To access the switch I will need to drill a small hole in the side of the nose cone. The hole will help to vent the altimeter, and the nose cone will also be vented to the body tube, which in turn will be vented to the outside air.
Any issues with this approach?
Does a hole the side of a nose cone produce any strange high or low pressure issues?

Aquaman33
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Re: Derek's Level 2 Build

Postby Aquaman33 » Fri Jun 26, 2020 9:48 am

I read about DavieRockets design for a simple deployment charge holder and liked the simplicity of it:
https://www.rocketryforum.com/threads/dual-deployment-charge-cups.49878/

It's basically a centrifuge tube housed in another tube that acts as the holder. Davie uses PVC, but I decided to 3D print something. This is my design:

Image Image

There is a hole in the bottom of the tube for the e-match wire and a hole to side for securing it to the bulkhead. The black powder is held tight against the e-match using a foam ear plug. The e-match wire will be secured to the centrifuge tube with some hot glue or epoxy.

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The centrifuge tube is a nice tight fit, but I will also put some masking tape over the end for extra security.

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I think this design will survive the blast and be reusable, but if it doesn't I can just print another.

Legendontour
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Re: Derek's Level 2 Build

Postby Legendontour » Fri Jun 26, 2020 12:31 pm

Unless your charges are less than 0.5g, you won’t be able to fit that earplug in there. I had to get the 2mL vials for 2g charges


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Aquaman33
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Re: Derek's Level 2 Build

Postby Aquaman33 » Fri Jun 26, 2020 1:42 pm

Legendontour wrote:Unless your charges are less than 0.5g, you won’t be able to fit that earplug in there. I had to get the 2mL vials for 2g charges


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Thanks Legendontour.

I was planning on trimming the ear plug for charges over 0.5g, but I also have 2ml vials on order. I can easily upsize my design to suit the larger vials.

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OverTheTop
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Re: Derek's Level 2 Build

Postby OverTheTop » Mon Jun 29, 2020 5:33 pm

I just use a bit of recovery wadding (crepe paper party streamers from a reputable supplier, for fire retardancy) and the cap that comes with the centrifuge tube. Do your tubes come with caps?

You could also use a layer of Kapton tape over the top. I am sure masking tape would suffice too.

Another alternative I have used before would be to make the 3D part accept the snap-in cap of the centrifuge vials, if you are trying to save mass.
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Aquaman33
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Re: Derek's Level 2 Build

Postby Aquaman33 » Tue Jun 30, 2020 6:41 pm

OverTheTop wrote:I just use a bit of recovery wadding (crepe paper party streamers from a reputable supplier, for fire retardancy) and the cap that comes with the centrifuge tube. Do your tubes come with caps?

You could also use a layer of Kapton tape over the top. I am sure masking tape would suffice too.

Another alternative I have used before would be to make the 3D part accept the snap-in cap of the centrifuge vials, if you are trying to save mass.


Yes they do come with caps. They are these ones:

Image

I decided to get rid of the cap so that it doesn't become a projectile, but I acknowledge that the risk of it causing any damage is quite low.

Aquaman33
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Re: Derek's Level 2 Build

Postby Aquaman33 » Tue Jun 30, 2020 6:50 pm

I wasn't entirely happy with the cable guides on by electronics bay, so instead of the fiddly little loops I redesigned it with channels or tunnels which are neater, easier to use and add a bit more strength.

Image

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I also tweaked the position of some of the holes and added stronger ribs.

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SpaceManMat
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Re: Derek's Level 2 Build

Postby SpaceManMat » Sat Jul 04, 2020 9:12 am

Coming along nicely Derek. Some good use of 3D printed parts.
QRS: 124
AMRS: 32 L2 RSO
Highest Altitude: 13,647 feet
Fastest Flight: Mach 1.55
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CATO
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Re: Derek's Level 2 Build

Postby CATO » Sat Jul 04, 2020 5:40 pm

SpaceManMat wrote:Coming along nicely Derek. Some good use of 3D printed parts.


+1
"In thrust we trust"

AMRS 21 L3 RSO
TRA 07459 L3

Impulse:
2020: 00,000 Ns (0% Z)
Ns 19: 14,725; 18: 14,767; 17: 5,973; 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: M1.14


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