Doorknob update: thanks to all who advised me!
The door is off the hinges and the doorknob is out.
Of course the pins, having lived in the hinges for 100 years, did not want to come out and took an hour of coaxing each.
Then the door itself was quite warped and didn't want to come off even after the pins were out.
But it's all out and everything is restorable and I don't have to buy a new door (because the size is no longer standard and it would have had to be done custom.)
A good result!
I couldn't have done it without you all!
= new reply since forum marked as read
You've earned it after all that work!
or do you have to take the door off the hinges everytime you want a cup of coffee?
I'm confused....
btw, standard door sizes; 2' 6" x 6' 8" or 30 inch x 80 inch, 2' 4" x 6' 8" or 28 inch x 80 inch, 2' 8" x 6' 8" or 32 inch x 80 inch, 3' 0" x 6' 8 " or 36 inch x 80 inch.
In older houses usually only pantry doors, storage area doors, basement doors vary, usually less than standard pre hung units. Reason being the builders didn't have time to mess around paying a carpenter to plane or cut 3/4 inches or less off the side of doors or bottoms of doors. They were money hungry bastages. Trust me on that.
I was just wondering how you got the old lockset out of the door if the bolt wouldn't slide.
Adding an inch to the bottom of a door isn't unheard of, standard doors measure 80" in height. that's all I was saying.
I'm retired after 50 years in carpentry construction and was just responding to your original post about getting the existing brass knob off.
After all that time I wish I would have specialized in building stairs and stairways. 
