Welding Tips and Tricks

Hey everyone, I'm having a weird issue with my machine. It's a used Eastwood TIG200 that has so far served me well. When I step on the pedal the amperage is exactly where I want it. I get a few dabs of filler in then it "goes to 11" and cooks a hole in my workpiece. I tried it on some scrap, and it starts fine, goes high for 2 or 3 seconds, then goes back to normal and keeps repeating the cycle. Any thoughts? Has anyone had a machine do this? I'm looking for a starting point to see what is wrong, I'm thinking the amperage adjustment control is failing. I'm also wondering if it's worth fixing a six year old welder that is now maybe worth $300, working.

I suspect something is wrong with the pot in the foot pedal, but you might almost need an oscilloscope to see what's going on. I'm not sure a meter will respond fast enough or would show you what's happening. Maybe set to ohms and range set to manual, you could follow the display well enough to see if it has hiccups when you press it. If you can open that and find a part number on the pot and it's available dirt cheap, I'd just replace it and see if that fixes the thing. If it's enough money to bother you, do more diagnosis before spending.

BugHunter wrote:I suspect something is wrong with the pot in the foot pedal, but you might almost need an oscilloscope to see what's going on. I'm not sure a meter will respond fast enough or would show you what's happening. Maybe set to ohms and range set to manual, you could follow the display well enough to see if it has hiccups when you press it. If you can open that and find a part number on the pot and it's available dirt cheap, I'd just replace it and see if that fixes the thing. If it's enough money to bother you, do more diagnosis before spending.

Good call. I just remembered I have an on/off finger button controller. I'll switch to that and and see if it stays steady. Don't know why I didn't think of that in the first place, probably because I never use it.