Drum Developing FB: Possible, But Not Reccomended
Although FB paper can be developed, stopped, and fixed in Jobo drums I recommend that you avoid doing so. FB paper increases size significantly as the mass of paper absorbs water in processing.
The paper is rolled into a cylinder shape in the drum with the paper end-to-end. Thereís no place for the paper to go as it expands, so the paper begins to buckle taking on the shape of the pressed steel walls of a Quonset Hut or the corrugated layer of cardboard shipping boxes . The longer the paper is left in the drum with the solutions, the more the paper increases size. The length of a Jobo drum is generous enough that the ends of the paper donít exert buckling force lengthwise.
If you simply develop, stop, and fix the paper in the drum, the buckling due to water absorption isnít too bad, but will need considerable flattening later. But washing, toning, or anything that increases the wet time constrained inside the drum is likely to expand the paper so much that it buckles the paper with sharp folds, ruining it.
By limiting the wet time in the drum to just enough to develop, stop, and fix, followed by washing and further steps carried out in trays itís possible to make a decent print. As you might expect, you have be especially careful to slowly scroll a soggy FB print away from the drum walls to remove it without damage.
Using trays or troughs is much less likely to hurt the print that youíve invested your time, effort, and money in making.