chute arrangement for dual deploy using a h550 or j270 motor

[Lt72884]

Something to think about. I do not use a checklist, but masking tape is my friend. Everthing I need to do is annotated on masking tape, and taped to the rocket near the item to which it refers. For example, "turn on alt #1" is taped next to the switch hole or the leads sticking out (twist and tape). This goes on for all components and the tape is removed after I complete the task. When there are no more maksing tape notes, it is ready to fly.

Great idea. With all my single deploy for lvl 1 and 2, i didnt need a check list because it was plug and chug, but with dual deploy, i now need something to remember all the stuff to turn on and listen for

 

[Titan II]

For the sake of consistancy, I recommend you just buy a couple hundred of these.

https://www.csrocketry.com/recovery-supplies/shear-pins/shear-pin-2/56.html

 

[Lt72884]

For the sake of consistancy, I recommend you just buy a couple hundred of these.

https://www.csrocketry.com/recovery-supplies/shear-pins/shear-pin-2/56.html

Thank you

Whats yhe force requirements to break these? My 0hone is not happy with the website and im not near my pc or i would look myself. Sorry

 

[David_Stack]

Thank you

Whats yhe force requirements to break these? My 0hone is not happy with the website and im not near my pc or i would look myself. Sorry

From a post by member tim cubbedge, reposting a chart originally made available by member blackjack2564...

 

[Lt72884]

View attachment 635004
From a post by member tim cubbedge, reposting a chart originally made available by member blackjack2564...

Awesome, thank you very much for this. I have all the formulas to find out how much gun powder i need.

 

[teepot]

I was looking at the picture. It shows the chute attached to the nose cone. Put your chute 3 feet or so from the NC. I would recommend shear pins. To make sure they don't tear the BT put blades either attached to the inside of the BT or on the nose cone. I use thin copper sheets to make blades. I use a Dremel to make a depression in the BT about an inch from the top edge of the BT. I have also put them on the nose cone when the BT is to thin to make a depression. I use my Dremel to make the depression in the nose cone. The blades I make are about an inch long and half an inch wide. I use medium CA to attach the blades. Once the blades are in I put a mark on the nose cone that lines up with the mark on the BT. Drill thru the BT and thru the blade and into the NC. You can tap the hole or make the hole slightly larger than the shear pin without tapping it. If using the slightly larger hole use a piece of tape over the head of the shear pin to hold it snugly in place. I started using a slightly over sized holes and slip the shear pin in. A lot easier than trying to screw the small pins in.

 

[Lt72884]

Discussed ad nauseum here on the forum.

Ran a search and came up with pages and pages of discussion: https://www.rocketryforum.com/search/584352/?q=shear+pins&o=relevance

I am sorry I didn't even see this reply I know my team used shear pins for our fiberglass build, but I wasn't sure about a basic cardboard rocket. Thank you for this link. I will be searching these posts tonight

 

[Lt72884]

I was looking at the picture. It shows the chute attached to the nose cone. Put your chute 3 feet or so from the NC. I would recommend shear pins. To make sure they don't tear the BT put blades either attached to the inside of the BT or on the nose cone. I use thin copper sheets to make blades. I use a Dremel to make a depression in the BT about an inch from the top edge of the BT. I have also put them on the nose cone when the BT is to thin to make a depression. I use my Dremel to make the depression in the nose cone. The blades I make are about an inch long and half an inch wide. I use medium CA to attach the blades. Once the blades are in I put a mark on the nose cone that lines up with the mark on the BT. Drill thru the BT and thru the blade and into the NC. You can tap the hole or make the hole slightly larger than the shear pin without tapping it. If using the slightly larger hole use a piece of tape over the head of the shear pin to hold it snugly in place. I started using a slightly over sized holes and slip the shear pin in. A lot easier than trying to screw the small pins in.

I have seen this done, a good idea for light card board. I think i have some brass or copper sheets laying around that i can use. Ill cut them in circles and attach to the inside

 

[3stoogesrocketry]

I have seen this done, a good idea for light card board. I think i have some brass or copper sheets laying around that i can use. Ill cut them in circles and attach to the inside

You can just use tape to friction fit the nose cone into the payload bay. I've used this method forever including on my 4 inch Lvl 3 rocket. Once your payload bay is complete and loaded, pick your payload bay up by the nose cone in a vertical orientation. Repetitive drop and raise the payload bay a foot or so by the cone only. If your payload bay slips off the cone, it's too loose. Think of your parachute and shock cord acting as a slide hammer.

 

[Lt72884]

You can just use tape to friction fit the nose cone into the payload bay. I've used this method forever including on my 4 inch Lvl 3 rocket. Once your payload bay is complete and loaded, pick your payload bay up by the nose cone in a vertical orientation. Repetitive drop and raise the payload bay a foot or so by the cone only. If your payload bay slips off the cone, it's too loose. Think of your parachute and shock cord acting as a slide hammer.

This is what i did for both L1 and L2 flights for single deploy. Wasnt sure if it would still work for dual deploy or if shear pins were needed due to possible extra forces from extra gunpowder

 

[3stoogesrocketry]

This is what i did for both L1 and L2 flights for single deploy. Wasnt sure if it would still work for dual deploy or if shear pins were needed due to possible extra forces from extra gunpowder

There should never be a large shock under correct deployment. Use the BP to generate the correct forces. 6 psi is alot in the correct setup. Ground test both sides.

 

[Banzai88]

I have seen this done, a good idea for light card board. I think i have some brass or copper sheets laying around that i can use. Ill cut them in circles and attach to the inside

There's a thread on that.

https://www.rocketryforum.com/threads/shear-pin-shear-plates-in-your-cardboard-tubes.136706/