Another spot welder question

Well, I'm getting this little portable spot welder figured out..... almost. About a quarter of the time the tip sticks (Welded?) to the sheet metal I'm
joining. It's 26ga uncoated steel and I'm joining two thicknesses. Can I do something to prevent the sticking? I also sometimes get 'burnthrough' (There is no timer control). I assume that is just too long an 'on' time; or am I wrong again?
Thanks once again.
Roger in Vegas Worlds Greatest Impulse Buyer
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Could be one or more things, Roger. Too long an on time could do it but so could too much clamping pressure. This would tend to embed the tip into the material. On 26 ga. you should be using about a 3/16 dia. tip and only enough pressure to get the parts to touch. Too much pressure actually decreases the resistance so you may end up with excessive weld time to compensate. Too much pressure may create a point of max resistance at the juncture of the tip and material as well. This could explain the sticking. In the words of a teenager of my acquintance: Lighten up.
Jerry
Roger Hull wrote:

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