help with wires

Hi everyone,

I'm building a rocket with electronics in the NC, and I was just wondering, wouldn't the ejection charge rip the wires when it blows the NC off? I know there's something I'm missing here, since a lot of people have done this but what is it?

Electronics go in NC, BP goes in payload separated by bulkhead.

TRFfan said:

Hi everyone,

I'm building a rocket with electronics in the NC, and I was just wondering, wouldn't the ejection charge rip the wires when it blows the NC off? I know there's something I'm missing here, since a lot of people have done this but what is it?

Click to expand...

As was said, the electronics and wires go in the e-bay area which is totally sealed off from all ejection charge force. Your wires should only protrude enough to connect to a wiring terminal or another method of reaching the charge. Don't have a lot of wire exposed. Also ensure you seal the hole they come out of in the bulkhead. Just a little hotmelt will do. Enough to keep the charge out of the internal ebay.

Yeah, you definitely don't want BP Ejecta contacting the electronic stuffs.
timbbucktoo pretty much summed it up.

I might not be understanding, but I have done many rockets with the altimeter in the nosecone. Whether I use a charge holder on the nosecone bulkhead, or it is a charge located farther down in the payload (centrifuge tube typically for me), the nosecone simply ejects and takes the wire and charge holder with it.

In a few cases I have had fixed holders at the bottom of the payload mounted on the bulkhead with control in the NC. In that case I tape the wires to the side of the payload interior and do four or five twists to hold the two separate pieces together. Wires then pull right apart at separation just as planned.

Hey trfan, is this for your 24mm MD rocket?
Why not elaborate if it is not!

Ok, just to clarify, ive provided a diagram of the rocket here that i made in paint. This isnt a actual scale model of the rocket, its just a diagram to help you get an idea of what the setup looks like. The code here is blue for wires, orange for the payload bay, and red for the blastcap.


View attachment 287634

So my concern here is that when the ejection charge blows, it will yank out the wires from one of its anchor points (or both) or it will rip the wires. I feel that theres something Im missing here, but I cant figure out what it is.

Any thoughts?

BTW, use the first image. The second one i attached accidentally and I couldn't get it out of the post.

timbucktoo said:

Hey trfan, is this for your 24mm MD rocket?
Why not elaborate if it is not!

Click to expand...

Yep, its for my MD. I gave a description in the post above.

Move your BP charge to other side of payload, attached to bulkhead so it "blows" the payload out. As stated before, there needs to be a bulkhead between electronics & charge.