Magma master pot

[waco]

How hard is it to hook up a PID to an RCBS pot? Is the PID something you have to build or can you buy them?

 

[Rick]

You can buy them, could I suppose even buy the Magma and install it on the RCBS. With the Magma there is no probe inside the pot and believe me that is really nice. The probe attaches to the outside bottom of the pot. The Magma is pricey though.

 

[waco]

You can buy them

Ideas on the best place to buy?

 

[KeithB]

I built one (actually a dual PID to control/monitor pot AND mold temperature) and it wasn't real hard. I suppose somebody sells them. With mine I have to stick a probe down into the pot, the pot is plugged into the PID unit and it just turns the power to the pot off and on. Have to turn the pot on all the way to effectively bypass the thermostat. I love mine, the quality of my bullets went up tremendously after I started using it.

Brad's unit is a neater setup.

 

[358156 hp]

It really, really looks like a Waage pot. I must look into this... I've been wanting a Waage pot for ages.

 

[358156 hp]

Here's a side view of my PID conversion to my Lyman MAG20, an RCBS conversion would be similar. My thermocouple is attached to the bottom of the pot, which made for a really clean conversion. You can see the thermocouple lead coming out the back.

 

[KeithB]

Here is a shot of my dual PID. I drilled and tapped an ingot to hold a pipe thread type probe. I also D/Ted several molds to monitor them, I just switch the probe. Gotta be carfeful not to let hot plate melt overheat, I turn the thermocouple down to preheat ingots while I'm monitoring mold temp. Monitoring mold temp really improves bullet quality for me.

 

[Rick]

Ideas on the best place to buy?

I dunno, I would have to look around. When I bought my Magma pot they didn't yet offer the PID, when they did start selling PID's you had the option of sending them your pot or installing it yourself. I bought Magma's PID and installed it myself. To do so the entire pot needs to come apart and a nut is welded to the exterior bottom of the pot, the wire for the controller attaches to this nut with a cap screw, remove the mechanical thermostat, re-assemble.

 

[Rick]

And here is an outstanding write up by Keith of building his dual PID controller. Complete with parts list and photo's.

Dual PID Temperature Controller

 

[Brad]

I bought my PID off a guy on CB years ago. Plug the RCBS into the PID and set temp. Like Keith said the PID turns the pot on and off to hold temp.
Most amazing thing is seeing what happens to pot temp when a cold ingot is added.

 

[waco]

Good stuff. Thanks guys.

 

[Pistolero]

"The most amazing thing is seeing what happens to pot temp when a cold ingot is added"
I assume it drops rapidly and then slowly comes back up, but particulars would be interesting
to hear.

Looks like a monster and well made. Should give good service. I need to connect up the PID I
purchased a while back for my RCBS bottom pour.

Bill

 

[Brad]

With my RCBS it takes the pot down from 700 to 660-670 if the pot is only down about an inch. Problem is that it takes 4-5 minutes to get back to 700. I often keep casting while it heats back up but if using a large cavity mould the pot can't keep up with the required ingot additions. Adding another ingot in the 690 range drops it back to 650.
Getting behind the curve sucks. An ingot heater would help as you are adding 200 degree ingots instead of 75 degree, or worse.
I have a couple pots and have often considered using one as a premelter. Use the ladle to move molten lead into the main pot then add ingots to the premelt. As long as the premelt stays molten who cares if it gets colder.

 

[KeithB]

I found out that monitoring mold temp really helps, maybe more than pot temp. Most of my molds cast well at 400-425F, and when they are up to temp I don't have to run the pot quite as hot. Also makes for very consistent diameters and weights. It's interesting to see how fast a mold loses heat when you're waving it around in the air with the blocks open. An open mold really loses heat fast, lots of surface area to radiate heat away.

 

[Brad]

That is why so many new casters have issues. Too busy looking at freshly cast bullets and not keeping the mould hot.
I judge mould temp by how long the sprue takes to set. If it gets a little longer then I slow the cadence a touch.

 

[KeithB]

Yes, that's the way I used to do it, and it's a good way. When you monitor your temps and your cadence you will get into a rhythm that matches the rise and fall of the mold temp.

 

[Ian]

Art and Science. You can cast by intuition or by rote, means to the same ends. I prefer both when possible, though I still have never used a temperature probe in a mould, IR temperature "gun" is as close as I get to that.

 

[358156 hp]

I bought my PID off a guy on CB years ago. Plug the RCBS into the PID and set temp. Like Keith said the PID turns the pot on and off to hold temp.
Most amazing thing is seeing what happens to pot temp when a cold ingot is added.

Or even when you set a cold ladle into the melt. The numbers drop a lot faster than they come back up, and go down much further than you might imagine. And your heat-treating oven? the factory thermostat is off. Guaranteed.

 

[waco]

Well Brad? Don't leave us hanging......let's see some of those bullet you cast today!

 

[Brad]

Patience, had to take the wife shooting. The 140 XTP grouped pretty well for her.
She is fighting her glasses. She needs readers and can either have a sharp front sight or sharp target. I had her go with a sharp sight and it seemed to help. Also working on position.

After 100 rounds of jacketed it doesn't have much copper fouling. I like that.