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Nose cone Avbay sled

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smugglervt

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My son laser cut this plywood avbay sled for the nose cone of my current Binder Design Thug build. Normally I would use a U-bolt to attach the recovery harness. He went and added a tab to the sled instead (he's not into rocketry). I'm not sure I would trust this type method for attaching my harness to the nose cone. It's 1/4" birch plywood. Should I give it a try and hope the tab holds with the motor ejection charge or should I cut the tab off and use the normal U-bolt configuration. Any thoughts?

AV 1.jpgAV 2.jpg
 

OverTheTop

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If you could do a metal ring insert (and glue it in) to spread the point force from the quicklink or harness around the hole a bit better it would probably work. Worth trying I think.
 

Tonimus

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I wouldn't use the tab. Just screams failure mode to me.

EDIT: I may walk that statement back a bit, as I don't know how heavy the cone or electronics are.
 
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ksaves2

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I wouldn't use the tab. Just screams failure mode to me.

EDIT: I may walk that statement back a bit, as I don't know how heavy the cone or electronics are.
I think you're right. One would have to be fastidious with the amount of charge. It's best to be overcharged by a little than undercharged. The mass of the tracker/battery is very important. I'd say ditch it, use a U-bolt and worry less.
The ring I'd like to see a bit thicker so there is more purchase for the epoxy to hold the whole thing together. I've used a ring and plate arrangement with four 4 inch nosecones and I've used a .6 inch thick ring to so there's quite a bit of area
for the Cotronics 4525 to hold the ring to the nosecone shoulder. Haven't flown them yet but hoping they'll hold up. Kurt
 

K'Tesh

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Why risk it?

Metal U bolts are proven technology, If the wood were to fail, you could hurt someone, or damage something, along with risking the loss and/or destruction of the electronics.
 

dhbarr

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If you could do a metal ring insert (and glue it in) to spread the point force from the quicklink or harness around the hole a bit better it would probably work. Worth trying I think.
A rolled rim grommet or threaded bushing could work for this. Add a layer of thin glass first, maybe another over the top to sandwich the flanges.

Not sure any weight or labor is saved, though.
 

smugglervt

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Thanks for the feedback everyone. I'm gonna go with my gut and cut the tab and go with the u-bolt.
 

cwbullet

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I have used a wooden tab with low power. I would not use it for high power.
 
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