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Does anyone have any idea if QJet ejection charges will be too hot for Cardstock?

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Retrospace101

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Hey there, on a thread I heard that Composite motors may destroy cardstock rockets, I know that the Aerotech D10 would kill one, however is it the same for Q-Jets? I’m not sure but they say “By Aerotech”
 

rharshberger

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Qjets are flown in lots of Estes type rockets, but your hand rolling cardstock tubes those may not be strong enough for any amount of pressure.
 

BEC

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Current Q-Jets have a pretty strong ejection charge in the 4s delay versions, with lesser ones in 6 and 8s delays. I would stay away from any of the earliest ones in a cardstock model (dates before September 2018).
 

Retrospace101

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Current Q-Jets have a pretty strong ejection charge in the 4s delay versions, with lesser ones in 6 and 8s delays. I would stay away from any of the earliest ones in a cardstock model (dates before September 2018).
so after Sept 2018? Got it.
 

afadeev

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so after Sept 2018? Got it.
You can do your own testing - build a sample tube from your cardstock, seal it with a nose cone, and ignite BP charges of various weight/volume. Document the maximum amount the tube withstands for your supply of cardstock and your building process.

Then empty the Q-jets BP charge into a container, re-weight BP amount to your spec, pour it back into Q-jet's ejection well, and fly with no worries!

a
 

BEC

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You can do your own testing - build a sample tube from your cardstock, seal it with a nose cone, and ignite BP charges of various weight/volume. Document the maximum amount the tube withstands for your supply of cardstock and your building process.

Then empty the Q-jets BP charge into a container, re-weight BP amount to your spec, pour it back into Q-jet's ejection well, and fly with no worries!

a
That is true....and I've done this with some pre 9/2018 Q-Jets myself.
 

GlenP

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Maybe depends on how you make the tube, I sometimes roll a two-ply cardstock tube with a little bit of overlap on the seam, those are pretty strong tubes, equal to a manufactured cardboard tube, and I have used D12 black powder motors with no problem in those 24mm tubes.

Some cardstock tubes are single ply and have a very narrow glue strip, either as a lap joint or a butt joint, those are designed for light weight and lower thrust 13mm and 18mm power, and probably not strong enough for D power. Even if you coat the inside of the tube with a light coat of white glue, it might not be strong enough.

Is there a particular card stock rocket you have already built, or are you planning to build one?
 

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