Fuji Diaphragm
$13.65
3-Pack of Plastic Diaphragms for 1Qt. (1000cc) Bottom-Feed Cups
The air hole in the diaphragm should be positioned at the rear of the cup (toward the handle) unless you intend on spraying upwards for any length of time
For spraying upwards, position the hole in the diaphragm toward the front of the spray gun
The idea is to keep the hole out of the paint as much as possible
These diaphragms, in combination with the pressure tube/check valve, solve the problem of paint backing up into the pressure tube
