Lee Pot temp incredibly stable!

[Hardcast416taylor]

I actually hate to admit the following. I met up with AJ Peacock for coffee, I bought. He had samples of the molds he is currently casting, a 120 gr. 9mm, a wadcutter .38 and the 220 gr. .338. I asked how long he had been casting as I rolled the boolits around looking for telltale flaws. He replied he had just started! The boolits looked as good as any I turn out, and I`ve been casting 40 years+. This guy has done his homework on casting technique. He also is buying coffee next time we meet up.Robert

[AJ Peacock]

I actually hate to admit the following. I met up with AJ Peacock for coffee, I bought. He had samples of the molds he is currently casting, a 120 gr. 9mm, a wadcutter .38 and the 220 gr. .338. I asked how long he had been casting as I rolled the boolits around looking for telltale flaws. He replied he had just started! The boolits looked as good as any I turn out, and I`ve been casting 40 years+. This guy has done his homework on casting technique. He also is buying coffee next time we meet up.Robert

Thanks Bob, You also bought breakfast, thanks again.

AJ

[Echo]

Thats isurprizing. Especially when adding sprues, culls, and emptying the pot.

When I add sprues back in, the temp drops by about 75+ degrees.

SHiloh

Which is why I pop my sprues back in as I cut them. They are still hot, and the mass is fairly low, so there is little effect on the melt.

[geargnasher]

AJ, I've been watching that PID thread, too!

FWIW, my Lee pro 4-20 (110 volt) usually struggles to keep up temp when brimming and overheats below 1/3, but that is to be expected. I cast between those levels, throwing back sprues every 10-20 pours or so, fluxing and stirring every other time I throw them back, sometimes adding an ingot with the sprues and taking a 5-minute potty/drink/snack/hand stretch break so it can heat up well again. If I do this the temp is stable to within 10* during casting. I'm very happy with my Lee for the "chips" I spent on it, and I didn't expect it to work very well either when I bought it, glad to hear someone else's is working as well too, but I can't justify building the pid toy now, either

Gear

[lathesmith]

As I cast, I'd occasionally drop the sprue's back into the pot. I made sure to drop the sprue's when the temp was up around 825F and this would drop the temp a degree or two (depending on how may sprue's I dropped in) When I was done, the pot was only 1/2 full but the temp was still holding steady.

AJ, as you have discovered, with a single- or even a double-cavity mold, the Lee 20lb pot doesn't really need any help in maintaining a reasonably stable casting temp. This can even sometimes be enhanced by covering the pot with a simple piece of aluminum foil...

However, as you point out, after an hour, the pot is still half-full; single- and double- cavity molds don't empty those 20lb pots very fast. With a 4- or especially 6- holer, the picture changes dramatically-- I can easily drain a full 20lb pot in less than 1/2 hour with any of my 45 caliber 6-bangers, and even my 358's aren't far behind. I have to constantly adjust my pot's temp control down as I am casting, and sometimes will cool my mold for a few seconds in front of a fan between pours to help regulate temperature.

Thanks for posting your experieces, I appreciate it. All this talk about PID's and thermometers has got me thinking about applying a little more of the scientific method to my casting, I need to get a good thermometer and see what's really going on, and then go from there. I'm sure I could benefit from a good PID setup, and it would reduce some of the temperature-fiddling that I have to do now. It's kinda like the tachometer that I put on my lathe--it's not really necessary to do good work, but it definitely improves consistency and repeatability of the finished product, which makes life easier all around.
lathesmith

[mpmarty]

I've got both the LEE pro 20-4 and a Lyman bottom pour. I keep a thermometer in the pot and while the Lyman varies up and down as the 'stat goes on and off I have to keep nudging the LEE dial to maintain even temps. I use the LEE more as the Lyman is an old ten pounder and I run six hole molds almost exclusively.

[techlava]

Which is why I pop my sprues back in as I cut them. They are still hot, and the mass is fairly low, so there is little effect on the melt.

It sure make less of a mess as well.

Using the ventilation fan to cool the mold to speed up cycling is "cool" also.