Making a 50lb bale with a Heston 1836 baler

Hello; Just purchased a new Heston 1836 Baler. Does anyone have a "Rule of Thumb" in setting up the baler to make a 50lb bale @ 18% moisture or is this going to be a trial by error process. I grow alfalfa/orchard grass mix and have been making mini round bales with a Star 850 round baler. My customers like the light wt bales. Thanks..

Making a 50lb bale with a Heston 1836 baler