11"x14"processing drum volumes

[Martin Rickards]

Years ago I made from PVC tubing an 11"x14" processing drum for RA4 chemistry. It worked reasonably well and I've been thinking of doing some more colour printing. However, I can't remember the volumes of chemistry that I used. Any ball park figures from those using drums for this size of paper?

 

[brbo]

Maybe start with 80ml and if there is no unevenness in developing try less end less? Depends mainly on how well the level position of the drum is maintained during rotation...

 

[halfaman]

Jobo ask for a minimum of 122 ml to print 11x14'' in a 2840 tank

 

[brbo]

With a Jobo 4541 drum (max. 12x16") I can definitely get a print with 80ml. Never bothered to look up how much Jobo thinks I should use...

 

[DREW WILEY]

I don't use Jobo brand drums, but that sounds about right, equivalent to 3 fl oz - provided the drum is running level and you've preheated the inside to the correct temp with a presoak. Small solution volumes adequate for the paper size might not be adequate to hold working temp inside the drum if it contains ambient air substantially different in temp. It was common for drum manufacturers to recommend a safety margin of surplus volume under the assumption the processor might not be ideally leveled.