Those WTCP irons are great, sometimes I could feel them switching, sort of = a mild "thunk". I still have one that works, although I don't use it any mo= re. Reminds me, I should get rid of stuff I don't use :) The pictures I saw of the WS80 showed a temperature knob, so it's likely a = newer model using different technology. Friendly regards, Bob ________________________________________ From: piclist-bounces@mit.edu on behalf of speff Sent: Wednesday, January 18, 2017 12:26 PM To: piclist@mit.edu Subject: Re: [EE} Making soldering iron bits Quoting Mr Smiley > On 18/01/17 01:02, Robin Bussell wrote: >> Weller WS80 > > I believe the Weller soldering iron bits contain a magnet that is used > to control the iron temperature > > > please correct me if I'm wrong > > > :o) > I believe you are wrong. On WTCP irons, the slug at the non-working end of = the interchangeable tips (the 'sensor') is made of an alloy with a Curie point as marked on the tip, so they are no longer *ferromagnetic* above the marked temperature. The permanent magnet is in the switch part. --sp --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .