Herz,
You make a lot of good points, and provide an alternative to my contribution - one of the great things about forums. Your points are worth discussing, so here goes.
The first questions anyone should have asked here is "where do you want the black lines and why?"
Sometimes people have their own reasons for trying things like this, and there are times when asking 'why?' could provide a better solution (if the aim is technical) and times when it may interfere (when the aim is expressive/experimental). The heart has reasons that reason does not know. Times when it is best to focus in on a good technical solution and times when it is best to open up to possibilities. When answering we have to make a judgment on which way to go. With questions like this I prefer to start the discussion by opening up possibilities without requiring the OP to justify themselves. But it is a judgment call. It often works the other way - everyone else gives what they think is the answer and I'm the only one who asks 'please tell us more'. I guess that another way of looking at it is whether or not you think that the scattergun answers might spark the imagination, or if they will hinder the path to the answer. If my not asking 'why?' in this case was wrong, it was because of my poor judgment not because of my lack of thought. It may not be obvious, but I tend to answer a few questions thoughtfully rather than a lot of questions summarily.
Oh, and if you don't mind me asking this, is it the right thing to do to tell other responders what they
should have done? Why not simply lead by example? I mean, I'm not going to say 'You should have answered this ten days ago while the fire was hot.' No, I'm not even going to mention that.
Whatever the reason, trying to do it by double development is going to cause problems.
I got the impression that frXnz was the sort of person who wanted to try things out, and find out the problems and possibilities for frXnzself.
Gelatine, the support medium for most photographic emulsions (including RC), is hygroscopic so it will readily absorb any liquid put on it.
This isn't much of a problem when the emulsion is dry as there are a number of effects which retard absorption (such as surface tension). But if the emulsion is wet - and no-one suggested drying the paper between processes - then any developer put onto the surface will 'bleed'.
I wondered whether or not to mention that, but I honestly thought that it would be self-evident, and that frXnz would quickly discover the different effects obtainable with sopping wet paper and with squeeged paper - going back to the willingness to experiment, which struck me as the essential flavour of this question that needed to be nurtured. In fact, if you have tried it, you will find that fairly fine work is possible with even fibre paper after it has been squeegeed onto an easel. There are some people who like little bits of imprecision and randomness in their process, especially among those using traditional methods, aren't there? Watercolour artists know the effect of painting onto wet paper, and I bet that most other people do too.
If the print has been given a second exposure (as suggested above) then the whole print has been fogged and development will occur wherever the developer goes. The results will be a bit like drawing on blotting paper with a marker pen.
You haven't tried it, or anything similar, have you? It is a lot more controllable than that, especially with RC. As part of the chemical dodging process (see my link to the APUG thread above) you paint developer onto wet fibre-based paper. Experimenting with that part of the process comes naturally - you can't help but try things.
Secondly, putting wet prints in enlarging easels is ill advised. Water will tend to cause corrosion of the metal (unless you have all stainless steel construction) and any residual chemicals will react with the metal to form salts (stop is very good for this). The net result will be a build up over repeated use leading to contamination and staining of subsequent prints.
I used all-metal easels when I began using chemical dodging, so that they could be easily washed and dried afterwards. You are worrying unnecessarily, possibly because you have never done it.
It is always best to keep dry areas dry in the darkroom so an alternative method should be found.
Well, that's a good idea, but it should not stop you from wandering from the straight and narrow now and then, if you clean your mess up afterwards. This is expression, not lab work.
If you are just wanting black borders around your print then nothing could be easier.
...
I didn't think that is what frXnz had in mind, I saw something more expressive. Maybe that was my mistake.
If you want lines on the print in other places for some other reason then try constructing a mask from red acetate using ruler, scalpel and a lot of care.
Expose the print, position mask (make sure it lies flat - a piece of glass on top will do this) and give second exposure. Then process.
With practice multiple masks can be constructed for complex effects.
There are other ways of doing this but this is the easiest.
I confess that I though that the easiest way that maintained the brushness frXnz seemed to want would be to paint them on in retouching dye, but I didn't dare mention it because it is so damn obvious, because frXnz knows what frXnz wants, but most of all because this doesn't seem to be about doing it the easiest way.
We do whatever we think is right at the time, I guess.
Best,
Helen