This was a first

[Jig Man]

It’s been around 100° lately and inside the garage it has been 94°.  I needed some football heads so I went out at 05:30 and plugged in the RCBS lead furnace.  The garage was 84° this morning.  After the lead melted I began pouring 1/2 oz jigs.  I am using hard lead and keep the pot on 8.  I was running a 24” oscillating fan about 20’ away.

Before I got a dozen poured the lead stopped flowing.  I turned off the fan and hit the pot nozzle with a propane torch.  It poured immediately.  I finished the 1/2 oz and started on 3/8 oz.  It wasn’t long before the lead stopped flowing again.  I turned off the fan and just let the pot set for about 5 minutes.  The lead began flowing again.  I turned the fan back on and continued pouring.  It stopped working for the third time so I just turned it off.  I’ll wait for cooler weather.

 I’ve never poured in this kind of heat and humidity before so this is a new experience.  In fact I’ve never even heard of anything like this.  Has this happened to you?

[cadman]

Jig Man,

    I can't say I've ever had this problem with my RCBS. However, I have not poured using my RCBS in the last month or in really hot high humid conditions. Now with the Lee10 lb pot, I have had issues. When it is hot and humid in my garage, I tend to get some incomplete pours or it seems like my pot runs cold sometimes ( where I get spout freeze up) where I light a match under the spout to get flow again. I believe what is happening is the pot maxes out on heat and since it is hot outside it doesn't cycle on/off as much as if it were colder outside. Until the lead temp drops the pot won't turn on.  When this happens the lead isn't as hot as it should be and doesn't want to pour well or fill the mold completely. When I run into this problem I try to pour really late in the evening or really early in  the morning. I've tried turning it up to a higher number and sometimes it works and sometimes the lead just seems too hot and it takes even longer for the pot to cycle. Unfortunately I don't have a 100% solution, because it doesn't happen all the time. I can tell you this, that I (would rather pour when its cold outside than in the hot humid summer. Try putting your fan closer to your pot maybe 3-5 feet away. This should cool your pot and make it cycle more. The only thing I am not sure about is with it being so hot, will this even help. Try it and let us know.

[Jig Man]

Thanks for the advice.  I hadn’t considered it being the pot itself.  I just assumed it was air cooling the spout.  As far as I know I am done until cold weather.  I just ran short of some and may need them next week.  

[jigmeister]

I read years ago that if lead is comprised of a mixed alloy that it can stratify into different layers of different metals that each have  different melting points.

If it is not getting stirred and separates I suppose something like you're experiencing could happen if the heavier metal at the bottom has a higher melting temp ??? 

I would say to also check the voltage level where the Pot is plugged into to make sure it's not lower than usual . Heat causes resistance to go up in electrical wiring and connections that can result in a voltage drop and less power to the Pot meaning the usual "8" setting is now lower .

As cadman stated above the high ambient temp in your garage would probably 

affect the operation of the thermostat . When they created the Lead pot during testing it was probably tested at a lower (typical) room temperature thinking nobody would be crazy enough to pour jigheads in 100 deg garages 

 

[Jig Man]

You may be on target there.  I’ve never been considered to be the brightest candle in the menorah.

[Munkin]

On 8/23/2023 at 11:16 AM, cadman said:

I can tell you this, that I (would rather pour when its cold outside than in the hot humid summer. 

 

Same here, I have 75% less issues pouring in cold weather than the hot humid summer.

 

Allen

[bassjiggin1955]

I have a 1200 sqft shop with 4 separate rooms 1 room for pouring 1 room for powder coating and ovens for baking 1 room for tying my baits and 1 room for my office.  I keep them at 70 degrees in the summer and 78/80 in winter it's all on solar.  

I have two older 1985/86 RCBS lead pouring pots 850 temp control I never have had any problem pouring. I had one rebuilt in 2018 and the other in 2021 both up grade temp controls but still are 850 temp. 

 

[NickQ]

The last but not least is the alloy purity. While we know that everything that's not lead will float that's not 100% accurate. 

Because of that I never flux in the bottom pour melter. I make sure the fluxing and mixing and such is done before pouring the ingots. The only ingots that will go into my bottom pour are impeccable cleanliness wise.

Another thing I do to prevent any temperature reading errors by the rheostat is having the bottom pour plugged to an external PID and the PID probe dipped into the pot. The pot is crancked up to the max and the PID doing the math. Since I started using the PID never had any issue. 

[jigmeister]

Did you set up the gain values for the PID controller yourself or did it come set up for a lead pot from the manufacturer ?

I would imagine you would not even need the Integral Gain setting since the  process of heating lead is so slow . Typically with a slow changing error signal all you need is the P and D gains  . 

[NickQ]

The good ole RCBS Pro-Melt are truly the absolute best melters money can buy for hobby lead casters. The bad part about them is that they don't make them anymore and the 2nd generation is quite a disappointment. Saw a used one for sale today on ebay and I was really tempted but I already have two.  

[Jig Man]

Heat, humidity, fan, I don’t know what caused the condition but it hasn’t happened since the weather changed. 

[robalo01]

I have noticed that I seem to have more problems pouring lead in hot weather. I always thought it was coincidence, but... maybe not?