I was getting my garage ready to run a welder awhile back. I thought hard about using my dryer plug and figured I would route it into the garage, make it a dedicated welder plug and buy a gas dryer. Much of what I read on the subject, however, indicated that the amperage capacity of the dryer circuit wouldn't be sufficient for the welder. Anyhow, I ended up putting a 60 amp sub panel in the garage and would recommend that as the best solution if you can afford to do it. That way, you get your 240v dedicated circuit and you have plenty of room in your box for 120v circuits should you decide to add lights, heaters, whatever. If you can manage the job yourself, you'll be able to do it for a reasonalble price (those panels are expensive though) but if you have to get it done by an electrician (as I did) get ready to dig deep. If you go that route, I recommend you use a licensed electrician. Good luck.
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