I have a couple of old internal doors fitted by the previous owners where thick carpets had been added later, and this has pushed both of them off one of the hinges (they each have two hinges). I’ve taken them down now in a bid to trim the bottom and fix them properly, but planing and sawing are proving troublesome as they are very old and seem to want to either crumble or splinter. Sanding works better, but seems like it would be an incredibly time consuming way to remove a few mm from the bottom. Another problem is that the frames are wonky - whether due to incompetence or ground movement is not clear - but I’d rather avoid changing anything about that unless I go all in and have someone fix this for me.
I don’t really have any power tools other than drills, but I’d like to solve this myself if I can, so would appreciate any advice. The doors are sort-of close to standard sizes (189x71cm and 196x76cm) despite their age, and I’d consider replacing them if it would help, but is there a service anywhere that can trim new doors to the right dimensions and treat them, or am I looking at getting help here really?