11"x14"processing drum volumes

Martin Rickards

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Joined

Dec 24, 2016

Messages

390

Location

Asturias, Spain

Format

35mm

• Mar 2, 2021

• #1

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

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Joined

Dec 28, 2011

Messages

2,161

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EU

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Multi Format

• Mar 2, 2021

• #2

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

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Joined

Sep 22, 2012

Messages

1,421

Location

Bilbao

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Multi Format

• Mar 2, 2021

• #3

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

 

brbo

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Joined

Dec 28, 2011

Messages

2,161

Location

EU

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Multi Format

• Mar 2, 2021

• #4

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

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Joined

Jul 14, 2011

Messages

14,132

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8x10 Format

• Mar 2, 2021

• #5

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.