That depends on what you do. Generally speaking, you can use DC welding machine. Advantages are lighter weight and lower requirements for power supply. It can generally be used at home for more than 20 years. For welding thin plates, you can buy an argon arc welder and rent an argon bottle from the market. Now the argon arc welding machine on the market can be used as an ordinary DC welding machine, but the output current of argon arc welding machine is very small. The maximum working current of general household is 170A-200A, and the maximum working current can be 4mm covered electrode. There are many brands of DC welding machines. Now the rectification technology is very mature and the quality is ok. Generally speaking, Ling Rui's is better, but there are many fakes. The key is to find more assured after-sales protection.