Loose leaf timetables were a benefit to railroad employees but they were not a benefit to timetable collectors. I, too, have a lot of both Penn Central and Conrail timetables and some I have just left wrapped as printed, some I have put in non railroad binders which seem to work reasonably well and a few years ago I got a bunch of obselete Amtrak binders of the same size as Conrail and I have put them to good use too. In the case of a timetable with general orders, I tend to keep two in one binder, one as complete with general orders as possible and the other as it was originally issued with all of the original pages and no general orders. If you want to wrap loose pages I would suggest wrapping them first with a piece of plain white paper then with a rubber band around the whole thing. Rubber bands do not last indefinately so you will need to replace them from time to time. Many Conrail timetables had a blank page in them, take a blank page with the holes punched in it with you if you go to buy binders so you will be sure that the rings match the holes. Also beware that there were a few timetables that were issued with holes mismatched to the original rings, some of them had new holes punched in them to match the rings and some left it to the employee to punch new holes to match the rings. Collecting timetables requires a certain amount of work but it is well worth the effort and they are interesting to read at all times at least for me and they have the operating history of the railroad as well.
Noel Weaver