3" clear tubing for upscale Magnum

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BDB

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I'm interested in upscaling my favorite old kit, the Estes Magnum. I'm tentatively planning to use 3" blue tube, and I'm trying to figure out the motor mounts for the two stages. (If you are a fan of the Magnum, you know that the booster motor has to be different than the sustainer.)

But the real problem I have at this point is the clear payload bay. I found these clear polycarbonate, acrylic and cellulose tubes at McMaster-Carr. Has anyone used something like this, or is there a better solution?
 

Cabernut

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3" Magnum upscale? Hell yes!

This has been in the back of my mind as well for some time. I once tried a test fit of the center section of a 2L bottle, slightly on the large size at 3.1" ID and flimsy too. I would be interested as well in good options. Looks like the link you have is a good place to start for something stronger.

By the way, I couldn't seem to find a 5:1 ogive 3" nose cone either which is what led me to shelf the idea. I'd be interested in seeing options for that as well.
 

Cl(VII)

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soopirV

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I'm interested in upscaling my favorite old kit, the Estes Magnum. I'm tentatively planning to use 3" blue tube, and I'm trying to figure out the motor mounts for the two stages. (If you are a fan of the Magnum, you know that the booster motor has to be different than the sustainer.)

But the real problem I have at this point is the clear payload bay. I found these clear polycarbonate, acrylic and cellulose tubes at McMaster-Carr. Has anyone used something like this, or is there a better solution?
I think you hit the nail on the head with the polycarbonate tubes...the acrylic has poor impact strength and the cellulose has poor tensile strength. The polycarb can handle both load and impact very well! Price is much better than I was expecting, too! Do a build thread! I cloned the Estes original, and used a piece of fluorescent tube cover to mimic the payload...looks only fair, not quite right.
 

caveduck

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Check out PETG tube - AFAIK this is what Estes actually uses for their kits with clear payloads. It's commonly used for packaging/shipping tubes and is surprisingly inexpensive even in larger sizes. Have a look at https://store.visipak.com/Thin-Wall-Round-Clear-Plastic-Tubes.html. The 3" size has .018 wall and costs a bit over $4 for a 4ft length. Polycarb is noticeably more expensive and usually comes in pretty thick wall sizes. For shorter lengths you could maybe use the packaging tubes that CTI motors come in, which I believe is also PETG.
 
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