Originally Posted by Daybreakbus
God bless!! I can't wait
There are a few ways of doing it...some using the existing hinge on one side and sometimes replacing the hinge with a piano hinge. You need to add rails to the top and bottom, to solidify the door panels into one piece. If you can weld, that's easy. But you can also rivet those rails, if you don't have a welder. The cheap and quick way to make those rails is to use a piece of 1/8-inch flat bar on the front and back. I prefer to cut one side out of square tube stock, though, as it leaves nice rounded edges...it's a good system if you have the tools.
Then you need to add a vertical filler strip in the middle, since you'll be removing the rubber trim from one side...maybe both...and you need to make the door wide enough to fill the opening. Most doors have glass, roughly split into a top third and the bottom is about 2/3 high. I remove the bottom panes and cover the bottom with steel, for both privacy and to allow for a place to install a lockset.
On the inside edges of the frame, at least on the lock side, you need to add a strip of something solid against which the door will swing and stop. You also put weatherstripping on this. 1/2-inch angle iron would work and you could rivet it to the frame, if you're not welding.
On the door I'm working on now, the doorification work is done. I'm cutting some custom design into the outside skin, though, so it's a bit more elaborate than a plain door.