Lee 4-20 and tight wad

[melloairman]

I use my 4-20 Lee pots a lot . And replaced the switches a couple of times . Bought a point file and filed the points a couple of times which solved the early shut off time for a while . But that also removed material and put less pressure on the points to stay closed . After barely getting through a pot of lead today . I pulled the top plate . Removed the nob and noticed that the tab that lines the nob on the shaft that is spot welded on to the shaft . Is also the stop plate that hits the base of the switch . Was able to bend the tab out enough to not contact the base of the switch which allows the switch to turn farther and increase pressure on the points . So they should stay in contact longer . Will have to see if it works another day . Ran out of time today . Has any one tried this before and if so did it work ? Marvin

[melloairman]

I used the pot today . Casting shed was the same temperature as last time . And I used the same alloy and thermometer as well . I was able to set the nob to the six o'clock position instead of on high . The pot was turning off before 6oo degrees and then turning back on in a few minutes . Today it took the lead temp up to 750 degrees and then I manually turned it down to maintain 750 degrees for casting .Marvin

[DaveInFloweryBranchGA]

Marvin,

I think as the Lee pots get older, those points become more and more of an issue. After thinking things over, I'm going to clean mine up for a while, but when they get to be too problematic, I'm going to invest in one of these cheapie PID's to run the pot and bypass the Lee problematic controller. Improve heating control and consistency while eliminating a problem part.

[Cmm_3940]

I agree with what Dave said, the best fix for the Lee temp control is to not use it.

[melloairman]

I have two Lee 4-20 bottom pour pots . This one I use for smelting and alloy mixing . It has had over five tons of lead go through it . I have replaced the heating element once as well as the switch and the spout . I think its done me well . At this point the first two pots that I alloy through it I have no problem . But on the third pot full when there is no cool down time between pots the switch started to shut off at about 600 degrees as well . So I did the no cost adjustment to the tab on it . Will have to see if it will help this pot out as it did my other one . Marvin

[retread]

I built a PID setup for mine and would NEVER fight one of those switches again. I set the temp I want and it stays there +/- 1 deg. no matter what the lead level is in the pot.
I think my total investment in the PID setup was about $65 in parts. Bite the bullet and don't look back. My $.02

[melloairman]

Had enough time today to alloy 3 pots of lead in my second pot . Made it all the way through all 3 pots with out it shutting its self off before 750 degrees . It is surprising what you can do with a screw driver and five minutes of time . Marvin