I too make the choice of plaster cloth vs. paper towels by the size of the job. The plaster gauze is easy, but can get expensive on larger projects - check out Pinnacle Peaks State Park in the next issue of OGR magazine.
You can make the paper towel technique easier for yourself in various ways. First, always use a heavy-duty industrial grade towel (like the brown or blue varieties). The white kitchen towels are too weak.
Next, use a slow-setting plaster or drywall compound. Nothing is more aggravating than having plaster-of-Paris or hydrocal set up in your bowl, and having to clean it out and mix a new batch.
The Structolite brand of plaster (from Home Depot) is cheap (about 25c a pound) and has an extremely slow setting time. I can mix one big batch in a huge bowl and dip paper towels all evening without it setting up. It actually takes several hours to fully set and cure. Slow setting drywall compounds are also available in powder form.
If you have a lot of nearly vertical surfaces to cover, the plaster gauze is easier to use. If you want to use the towels on vertical surfaces, use the roll type so that you can go from top to bottom of the cliff with a single, long, plaster dipped piece of towel. Smaller pieces will tend to slide.
Also, there's no reason why you can't use both methods. You can use the cheaper towels in the easy areas, and save the plaster gauze for the trickier situations.
Finally, whether you use the plaster gauze or the towels, remember that this is just the initial shell. Don't expect this to be strong enough for the final mountain. Applying extra layers of gauze is just wasting money. Instead, cover your initial shell with a good thick (1/4") layer of Structolite or Sculptamold. This is what provides the real strength for your scenery.
Jim
