I have a 220 50 amp circuit in my shop for welding which I will use for my 220 bandsaw. Is there any reason not to make a 220 extension cord that would make it easier to change out plugs?
Maybe a gang box with a couple of plugs? I wouldn't be running two tools at a time, but the convenience would be great.
I'm sure someone here has done that so would you give me some tips?
I am a licensed electrician, and woodworker.
Yes, you can use an 8 awg extension cord, which will be large enough to protect your EXTENSION CORD for the given circuit it is plugged into.
BUT that is only half of the problem. What is the maximum circuit size your 220v bandsaw is rated for? 20 amps? 30 amps? Putting a power tool on a 50 amp circuit (circuit breaker size, not wire size) when the tool connected is only rated to be on a 20 or 30 amp maximum circuit, will leave your BANDSAW unprotected in the event of an over-current. Check your owners manual for the bandsaw, to verify the maximum circuit size allowed for this tool. If you want to use the welder circuit to feed the bandsaw, you may need to install a smaller circuit breaker or fuses at the electrical panel, to meet requirements for the bandsaw.
Please remember this quote: Electricity has a way of weeding out the Stupid!
If you are not qualified, it is best to leave electrical work for those who are.
I am not saying this to insult you, just to caution you on the potential dangers involved.