I DIY'd a terrarium for my gerbils and found the perfect material to use for the lid- a fireplace gate from the thrift shop ($5!!). The only issue is that I just need one of the doors and I can't get them separated from the frame.
10Important fact, in almost every way you take this off be sure to grab eye protection (even a hand saw can fling metal bits right into your eye) and dust mask as power tools will turn the material you're cutting away into a fine particulate dust that you will inhale -- it's better to get caught in the mask filtration then your nose hairs (or worse your lungs)– SidneyFeb 13 at 15:36
Angle grinder is the common way. Cut/grind the welds off.
A cutting torch does a nice job.
A saw(hand or powered) with a metal cutting blade is another way, but one of the slowest.
Can also try a sledge hammer and break the welds.
Have you tried just lifting one side off?
try a sledge hammer and break the welds... that would probably distort the door frame– jsotolaFeb 13 at 2:06
Depends on how you support the frame and how frangible the welds are, but...– keshlamFeb 13 at 2:19
3A flap disk on the angle grinder will do a great job of knocking any lumps off after the grinding/cutting step. Feb 13 at 3:10
9depending on how heavy this is, a decent sized (not a junior) hacksaw wouldn't be a huge pain for someone without an angle grinder. I'd make sure to have a decent metal file too, to take off the sharp bits, and cut it as close to flat as I can, but that's half an hours work– lupeFeb 13 at 12:59
If you lift the door, it will come off the frame.
Then use a angle grinder with cutting blade to carefully cut off the welded part.
Go slowly so as not to make a hole while removing the welded part.
5It looks from the photo that the hinges are opposed, in which case it won't lift off. Should still be able to angle-grind it in situ, though. Feb 13 at 11:45
I would take a punch and mallet and see if you can't tap out the pins.
Mallet, not a hammer. We don't use hammers on punches because the steel in a hammer is too hard and can chip upon impact causing injuries. When mallets are made of steel the steel is not as hard.
Last I heard, "hitting tools together causes chips" isn't an issue with any modern tools. The usual form of this advice I've heard is "don't hit two hammers together," and that's been proven to only be an issue with steel made from century-plus-old techniques. Feb 13 at 18:24
2@PotatoEngineer Perhaps but you could also just have crappy tools lol or tools from a lot that didn't come out quite right– DKNguyenFeb 13 at 18:25
@PotatoEngineer true - but we have no idea how old OP's tools are. And mushroomed punches look ugly.– CriggieFeb 14 at 0:49
Use of angle grinder, but with a thin cutting disc will be the best, but watch there are no windows, or any other glass in line of the sparks created. Once one hinge is off, lift off the opposing one, for better access.
A Dremel may get in closer and more tidily, with the correct attachment. Otherwise it's down to junior hacksaw (weld is usually quite tough to saw through) if you have an hour or two to spare, and then you'll still need to grind or file the rough remains.
Personally, I'd get the oxy-acetylene out, and very carefully unweld the hinge, but not many will have that luxury!