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Another note: after brazing, you'll need to cut the needle to size, which is hard to do without bending it slightly. It doesn't matter if the inlet side of the needle is slightly bent, but if the needle is bent on the outlet side, it will lose concentricity with the annulus and produce uneven combustion. The uneven combustion may not be a problem, but I'd be very careful when cutting the needle down to size!
Please make sure to leak test the brazed joint if you don't want to blow up; it's an interpropellant seal!
Chamber
add cross sections
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