Processing Drum questions for ra-4

[1kgcoffee]

I'm curious about doing some ra-4 printing.

Obviously, trays won't work for this. I'd like to print big, 16x20 or 20x24. Before I commit:

#1, will prints that are processed in the drum of designated size process evenly, or will I have problems with the paper sticking to itself and not developing properly.

#2, are there reasonably priced drums for 20x24, or is 16x20 the limit? It seems cut sheet of 20x24 are hard to come by but I would love to print BIG. Can I print two 8x10s in a 16x20?

#3, Besides jobo, what are the best rollers?

-thanks in advance.

 

[pinholer]

Your prints will process evenly. The paper lies against the wall of the tube and is held in place by ridges in the wall. The Jobo processor makes two revolutions before it reverses which insures that all of the paper gets developed. You could get uneven development if the tube was not level or if you used insufficient developer.

You can develop two 8x10s in an 11x16 drum.

 

[btaylor]

I used to develop 4 8x10's in a 16x20 Unicolor drum back in the day, no problem. 20x24 drums existed (I have one) but I never used it. Fuji paper is available in cut sheets up to 20x24. Any of the old rollers (Beseler or Unicolor) will work fine, you don't need a Jobo. I have heard of many people using open trays. Personally, I can't stand the smell so I won't. It is easy and cheap to get into RA4 printing... and a lot of fun.

 

[bvy]

Drums and motor base are my m.o. for color printing. I use Unicolor drums and a Uniroller auto reversing motor base. Development is even. 16x20 is the largest I've printed (with a drum that size) and it worked fine. The biggest issue you may have is getting such a large piece of paper into the drum in total darkness. As mentioned, the paper fits into grooves on the inside wall of the drum, and it can be tricky to align it without nicking or bending the paper.

If you're printing one sheet at a time, there should be no issues with the paper sticking or overlapping. However, some drums will allow you to print multiple sheets. For example, the 16x20 drum can hold four 8x10 sheets. In this case, two sheets will share one side of the drum. Unicolor made separators that fit into the grooves to keep the paper in place. They're hard to find now. I made something with nylon tie straps to handle this situation, but truthfully, I don't do this very often. I'm fine printing one or two things at a time.