[TheForge] propane forge - plumbing size vs flow?

[Jim Brattin]

hi all
i'm working on designing the propane plumbing for a three burner gas forge
burners will be two 3/4" and one probably 1" or another 3/4"
each burner ( i think) would be 1/8"pipe to .035 mig orifice
for the plumbing running from propane tank up to a cross fitting, wondering
if 1/4" is sufficient
or if 3/8" might be necessary for sufficient volume of flow?
in other words, 1/4" or 3/8" supply in, three 1/8" outlets
i know pressure and size and temperature of the propane supply are also
factors,
just not sure what's the ideal set-up...
thanks