what size wire do i need for welder in garage

[davesparks]

200 amp did you say?!
From a house?

That’s welder output current, not input current

 

[Spoon]

That’s welder output current, not input current

Yep, the OP clarified this in post #12

 

[uksrevivor]

The OP has neither stated what type of welder it is MIG/TIG/ARC or ARC/TIG Inverter. All of which will have a different supply requirement.

 

[telectrix]

or buy a gas welder.

 

[uksrevivor]

or buy a gas welder.

Those were the days, a fine art that is pretty much obsolete now oxy acetylene welding.

 

[telectrix]

last bit of that i did was 1966, apprenticeship time.making a steel toolbox.

 

[uksrevivor]

Mine was in 1992 a little bit after yours Telectric lol but strangely mine to was making a steel toolbox which was thankfully stolen by some thieving herbert. I just wished at the time that they left my tools contained inside on the workbench and took the box on its own.

 

[ruston]

I still have a sapphire torch and pipes. No bottles now though , I still have access to all the gear though . Even my favorite 'hot spanner'.

 

[uksrevivor]

That 'hot spanner' wouldn't be the one you borrowed years ago would it like the BOC bottle and regulator spanner

 

[ruston]

Aye , do you want it back. I fixed the broken glass on the regulator.

 

[Spoon]

...but strangely mine to was making a steel toolbox which was thankfully stolen by some thieving herbert

At least you got his first name...

 

[Bellendian]

Are you sure you need 200 welding amps? If so then yes you're going to need to upgrade the supply to the garage. It might work out cheaper and easier to get a welder/generator kit.
Unless you are convinced you need that sort of welding amps the simplest solution would likely be one of the smaller setups that will run off a std 13a socket. Typically you'll get up to 130 to 150 welding amps on a MIG with a plug on it.