Can an inexpensive jigsaw cut through steel if you use a good quality blade, and what blade would be the best if I have a cheap little Craftsman? I don't have the confidence to use my circular saw for this job, and using my sawzall for this job seems to require an awful lot of muscle.
If you're comfortable using your jigsaw (you know how it acts and reacts, etc.), it should be fine with a good blade. Any premium metal-cutting blade will do this job. Go slow and use oil.
Keep in mind that you're essentially "roughing in" for a mail slot. The slot itself will cover any sloppiness of yours, so long as it isn't too bad. So essentially all you have to do is get the hole big enough to pass the slot itself and small enough to give the mounting hardware something to bite.
Check with your postoffice first. I installed a mail slot in my front door several years ago to match what most of the neighbors had. Carrier wouldn't deliver mail to it. Apparently part of a program to get mailboxes moved to the curb. Or possibly some screwed up local policy. So I patched the door and rehung the old box beside the door. Didn't want to argue with that kind of mentality.
SJF
One cautionary note. The bottom of your saw shoe can scratch the door. Simply apply masking tape to the door or the shoe as a guard. BTW, your choice of 'weapons' is the best one!
It can work. The steel doors are not all that heavy and have a solid core inside. Just take it slow and keep a spare blade or two on hand. Fine tooth metal cutting blade will work. Drill holes at the corners to make it easier, of course.
Thanks to Bo, Edwin, C&M, and SJF. SJF, I *really* appreciate this head's up. The US Post Office is run by prima donnas from the top down (sorry if I offend anyone, but I got a s&%tload of problematic encounters with their methods of service, including one mailman who HURLED a first class package two stories rather than carry it to a porch!). I will Definitely check on whether they'll use the slot before I install it.
In my town they don't leave the seats of their mail trucks for anything. And god forbid the trash pickup leaves the barrels in front of the mailbox, they just knock them out of the way with the mail truck.
Many residential steel doors have foam cores with thin steel covering. The problem with cutting one is not cutting. It can be easily cut with tin snips. Just use a hole saw the size of the opening and drill each side. The problem is finishing. there will now be sharp metal edges exposed with foam center. Mail carriers can cut themselves when pushing mail though. It is hard to install the new slot tightly do to no solid material between the steel skin. If you are in a cold climate wind blows though these slots like a sieve. As you can tell I think they are a last resort option. There must be a better way to get you mail.
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