Question on 3D printed canon design and regulators

[nico]

I’m designing a propane powered canon which will be entirely covered by an aesthetic 3D printed shell. I've run into the problem with regulators which I can’t figure out. I think that the norm around here is to use regulators which were originally intended for compressed air tools. Don't these typically vent to relieve pressure? I was thinking on using this https://www.homedepot.com/p/Husky-1-4-i ... /205331831 but I can’t if it’s going to pool propane in my shell along with my electronics. Any ideas on how to proceed?

[jimmy101]

Regulators don't vent to relieve pressure once they are set. The only time they vent is when you drop the set pressure. If you aren't fiddling with the pressure it wont be venting.

I don't think using a regulator is the norm. I think it is more common to assume a particular pressure in the propane tank and then use a properly sized meter pipe to measure the correct volume at that pressure. The pressure in a propane tank is basically constant at a constant temperature (at least, it is constant until the tank reaches the point where it no longer contains any liquid propane.)

[Cthulhu]

Just use a regular propane meter if you really want to be accurate. They are pretty cheap and common at Lowes and home Depot.
Then set it up into a classic meter.