Some questions regarding rockets and material

[NASAFanboy]

Let's say you have to build a custom metal rocket nozzle, or a rocket tank. Do you know if you could place a order with a small model and specifications, and have the metal shop construct it?

Also, any ideas about how PVC piping behaves in supersonic flight, and estimates on how far a cluster of extended G80 motors will take. Also, could you "stack" rocket motors by cutting off their top and affixing another motor with a cut off bottom for a greater burn time?

if you are the FAA or FBI please look away and forget this.

[lajoswinkler]

Yes, you can order it. Metal shops can use a lathe to make you a nozzle out of most construction metals. Maybe not every shop, but in general they do it. I'm not sure about the prices, though. It's probably not cheap unless you find a really good deal, simply because that's one order instead of series of orders.

Custom made nozzle is for advanced rockets where de Laval shape actually means something. If you're building anything less sophisticated than those things people launch in Nevada, you can go with approximations or even regular holes.

Use high pressure PVC pipes for engine blocks, and mount them in rocket body made of lighter, thinner, more rigid polymers. You can make engine blocks out of rcandy for fuel, gypsum for nozzle and hot glue for sealing the top. Keep them in small, tightly closed containers because they're hygroscopic. It's almost an art to get the best results.

No, you can't do that with engines. The point of contact will become the point of violent breakup. Don't do that unless you want CATO.

[NASAFanboy]

Also, would R-candy be useful for a suborbital rocket launch, or will we need a better fuel?

I have qualms about its low ISP. I need a rocket fuel that can provide me with a good ISP and can be built with off the shelf matierals, or perhaps a cluster of motors that can get me to suborbit. Once again, FAA, pay no attention.

Edited October 16, 2014 by NASAFanboy