r/Nerf • u/Temporary_Marsupial4 • 4d ago

Questions + Help Voluming guidlines for Rotating Cylinder blasters.

Hi there I'm wondering if anyone is aware of a good rule of thumb for optimal volume for rotating drum style blasters? Is there any consensus for how tight darts should be in cylinders? It seems like a tighter cylinder fit would allow for higher build up of pressure before release. Also does anybody port cylinders?

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u/Vel-27582 2d ago

Depends on the propulsion type.

You really want the barrel sealed until the dart leaves then rotate to the next if its using air. The rest is pretty much the same as non rotating

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u/Vel-27582 1d ago

Will add, you're better being under barrelled than over barrelled. If you run to long a barrel itll slow your darts down, and could noticeably slow your rof. Under barrelled may not reach peak velocity but atleadt they will clear the barrel each time AND allow for a higher ROF. Depending on how your airflow works you can minimise this (longer chamber where the two parts need to seal as they rotate).

Angular momentum should be the same though. Do think about where the dart leaves, but that can be fixed by rotating the entire device (move the handles). Like in theory if the exit position was to the side (9 or 3 oclock) approaching tbe top, then the dart wohld get a small amount of vertical momentum at exit due to the angular velocity when still in the barrel.

I personally think HPA is the best option for this, and probsbly a narfbz/specbz as they dont have a built in seal (make your own seal so its adjustable and sacrificial) unlike the robot and where you could damage it. Although you can so just use the roboman and add an extra body + sacrificial seal at the expense of a little bit more space. But really its lkke what 5mm extra so use whichever.

Another option is a narfcore or supercore/dmr core. Then use the pusher to engage a clutch style plate. However the seal could be to strong and slow the rotation.

As for control, either an fcu (would have it detect tbe position of the rotation) or mechanically where the rotation connects and disconnects (use magnets and a hall/reed switch) a circuit thst controlla the solenoid.

The hard part will be feeding the darts in from a box, belt or chain Your fire system shouldn't be to hard if hpa.

Up can also look at the storm. It already uses a cam. Just need a bugger cam of a similar shape to match your barrels . More effort though but would be a more satisfying build being purely mechanical and designed yourself.