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What size Mig welder would i need to buy to weld 5 mm sheeting & fill pitting in hull of boat ? [mild steel] Answered

I will be preping the hull with wire brush & Needle descaler , cut and grind V for patches.



Best Answer 8 years ago

125 amp max should be plenty.

Practice a bunch before you try on your boat.  Mig welders are really easy to use once you get the hang of it. 

Thankyou all for your input.
Im not sure what Coogar & Ferromax is though ??

They are professional gas mixes for welding steels. They are much more effective than CO2. They are mixtures of CO2, Argon and traces of Oxygen.

Ask at your welding suppliers, and don't be fobbed off by "everyone else uses CO2".

Excellent,,, but,
This is an open area, often windy.So being Gasless aswell . Is there a wire [containing flux] that will be just as effective and what size wire ?

I know im a bit lit but the innercored flux wire isnt as good. Sure its a nice thing to not need the tanks but the flux cored spatters and smokes a bit more. A cleaner profesional looking weld can be acheived with practice but the gas would help alot. Just saying. I have a gasless and its pretty good. Even fluxcored will be effected a little bit by wind!

Not familiar with gas-less Migs, but AFAIK, they don't like wind much either, the "gas" is formed by the core.


Clamp tarps to the hull with magnets, to create a wind-free working space.


Unless you need it in the future look at hiring. You get a lot more for your money that way and possibly a professional quality set of kit.

Just a pro-tip,  DON'T use CO2, start straight away on COOGAR or Ferromax.

MUCH better penetration and cleaner welds.