Plation Soldering Station - can I trust it?

[ULfholt]

I have built some of these stations, and I'm not sure I can trust this thing. Two times the expensive soldering tip has burned up (suddenly got red and then stopped working) and I cannot tell why. Last time it happened, I saw the tip starting to get red and I managed to swithc it of. When I tried to turn it on after a few minutes, it worked OK for a while, but then suddenly, while I was getting something from my book shelf, the same thing happened, and I was to late to save the tip.

Have anyone had the sane experience, and can someone tell me why this is happening? I have not made any modification to the project and I'm using the recomended parts, though I have purchased most of the parts from eBay.

Best regards

Ulf Holt