It was bound to happen, I suppose

[358156 hp]

I've known that the thermocouple in my lead pot was getting bad for some time. I know how to get around the issue, so I've been putting replacement off. It wouldn't initially register temps below about 100 degrees after the first few months. My solution was to plug in my long TC that did work, & then swap back over to my pot mounted TC. My pot mounted TC mounts through a hole in the bottom of the pot so that it directly contacts the alloy in the pot. Anyway, I got away with this for about a year. Then last week I had to reject a full batch of 45 ACP bullets because of excess flaws. The PID was set at 720, but everything indicated I needed more heat. So I dug out my trusty old Lyman pot thermometer and checked the molten alloy against it. I was about 50 degrees low on temp. My 4 cavity Lyman won't cast well that low.

So today I drained the pot, and replaced the TC. I keep spares, so I at least had that going for me. I could have used the long TC for awhile, but everything else I tried today didn't work out and I needed a victory. So I did it, and damaged the first TC I installed by overtightening it. The second one worked just fine though. Now I need to buy a couple more spares.

 

[Brad]

How is your thermocouple attached to the pot? Mine is held in place by a little clamp on the rod for the pour spout. Mine is less than ideal.

You have my admiration for using a 4 cav Lyman mould. Those suckers are heavy!

 

[Ian]

I've been sweating the bi-metal 'stat going out on my Lee pot for a while. I could buy spares, but I need an excuse to buy a bigger and better pot so I'll just keep waiting for this one to die.

 

[358156 hp]

I drilled a hole in the bottom of the pot and installed a small button style thermocouple with copper washers on both sides. I put the proper style TC socket on the PID itself so I could plug in whatever TC suited my needs. Tom and I both did our PIDs that way so we could use them with diffeerent TC designs for different jobs. I wanted a submerged TC on my Lyman pot because I almost exclusively ladle cast. Tom used a similar design. All we need to do is plug in the long TCs if we want to use the PIDs for heat-treating, powder coating or other worthy projects. After a year with them, we're both gathering parts to build at least one more for each of us. We both plan on painting and Cerakoting, so the spare PIDs will likely be used for curing ovens. Ironically, we have access to a rather large commercial heat-treating oven at the shop, but I'll likely do most of my painting at home, and a PID controlling what amounts to an electric Brinkman smoker should handle anything I would do at home.

 

[358156 hp]

Ho, ho, ho. I filled the pot tonight, and fired 'er up. The second thermocouple reads every temp as 39.2 degrees. It must be mismarked or something. Either that, or I have discovered low-temp lino. I checked it against the long TC and my Lyman thermometer, which both read 720 degrees. If I hadn't been watching it closely, it would have melted half-way to China by now. Ho, ho, ho indeed. I haven't laughed this much in years. I'll order more TCs from Auber tonight, and just use my spare pot until they arrive. No big deal, it just makes my list of failures from Sunday complete.

 

[Brad]

Lino that melts at 39.2 F°?

Keep it away from Ian and his place, his ammo would drip right out of his gun

 

[Ian]

No kidding. Cerrobend will melt on a dashboard here in the summer.

 

[358156 hp]

"It melts in your mouth, not in your hand".
Lino flavored ice cream... There could be a market.

 

[Brad]

Leaves a tinny taste in my mouth. Yuck

 

[358156 hp]

Well.... I guess they don't make TCs like they used to. My new TC blew out around the OD of the sensor itself. I'm baffled as to how my original TC lasted over a year, but I had three failures in a row with the replacements. Time for a good solid "Plan C". I just ordered a different style TC from Auber that mounts to the exterior of the pot with a screw. I'll use a short bolt & nut to seal the original hole in the bottom of the pot, and drill and tap a hole in the head of the bolt for the TC probe mounting screw.

Okay, no pics then.
http://www.auberins.com/index.php?main_page=product_info&cPath=20_3&products_id=307