Quote Originally Posted by Rambozo View Post
Just so you are aware, the plug you show for your welder is a 30 amp 125 volt plug NOT 240 volt. While it will work fine and you might want to use it because you have a big cord with those ends, be careful that you don't plug an RV into that (it's an RV plug). I would NOT wire an extra outlet with that plug to 240 volt or put that plug on your dryer. If anything make an adapter so it will only get used for your welder.
This caution against using a plug makes sense because of what someone *else* might do in your absence. Since you are building it and you know what it is meant to do then you'd be fine- but someone else stepping into the picture (nosy neighbor, brother from out of town, whatever) might unknowingly plug it in to the wrong receptacle and toast it.

Are the wires that make up the extension cord beefy enough for the task?