[bang-on]

<font color='#0000FF'>john,
given a few empty j's and a good compressor i connect the full j of he to two more j's (emptys but o2 clean with the nonreturn valves removed) and allow them to equalise fairly slowly.
i then check the pressure across the 3 cylinders,this figure then dictates how much o2 to add for the required mix.
after adding the o2 slowly i then connect the whip to a personnell filter and on to the compressor outlet this then brings up the pressure to my desired amount. &nbsp;
now i have about 141 lts of a mix this can then be decanted back into diving cylinders when pressure drops in the three cylinders i can then coonect the whip to the inlet of the compressor and top of the cylinders being filled.
with the use of a needle valve on the end of the whip i can control the flow to the compressor and totally empty the j's.
notes;
uses all avaible helium.
is good if your doing a lot of deeper stuff.
diving cylinders being filled do not need to be o2 clean as only a small % of o2 is normally present in trimix.
you could have a slight drop in he in mix after topping of through a compressor so a he analyser is a good idea.
i label j cylinder before returning empty to supplier asking for &nbsp;it to be cleaned.
this works for me and i do not suggest it is safe or recommended &nbsp;practice.
cheers
barrie