Hey Leah's Mom
When you have a pneumatic (air) press, you have to feed it compressed air from a compressor or tank. So when I say line pressure, that is the air pressure in the line feeding the air press. My air press has a multiplier of 5 times, so if I apply 2 psi to the air press it multiplies by 5 and give me 10lbs press on the follower. If I apply 100 psi to the air press it is 500 lbs. If you don't have a air press you don't have to worry about line pressure. My follower is a 7" so that is why I used an 7" in my example, there is no real standard when it comes to this, you have to calculate the psi and lbs based on the size of follower you use. Hope this helps, this is always confussioning because most recipes do not state what size of follower they are using when they quote the press weights. I think most assume a 4" follower, so if you use a 4" follower you can use there weights, but if your follower is a 6" you need to increase the press weight to match the same psi on the 4".
Mike
