cadman Posted February 16, 2011 Report Share Posted February 16, 2011 (edited) I have this question that has been bothering me regarding my Lee IV bottom pour pot. Here is the scenario and a test I did. I keep my lead pot in the garage and it has been 40 degrees fahrenheit in there for the past several weeks. During these weeks, I have been using it with no problem. Then one day I thought to myself, maybe if I put the pot in my house, and it would stay at room temperature(68 degrees) then when I decide to use it I could take it in the garage and plug it in. The thought here was that if the pot was warmer, it wouldn't take as long to heat up and I can start pouring quicker. What I found was the opposite. The colder pot heated up faster to melting point than the warmer one did.This made no sense to me. So I did this several times and timed it from plugging it in to when the whole pot was liquid. The cold pot won every time by about 15 minutes How is this possible? The only thing I can think of is that the pot heats more continuously because the t-stat is telling the pot it is cold versus taking it out of the house where it is warm and then putting it in the garage and plugging it in. Can anyone shed light on this subject? I am just curious and want to know. Edited February 16, 2011 by cadman Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted February 16, 2011 Report Share Posted February 16, 2011 I think you nailed the only feasible explanation. It makes sense to me. Dave Quote Link to comment Share on other sites More sharing options...
Jig Man Posted February 16, 2011 Report Share Posted February 16, 2011 That is a physics problem related to British Thermal Units converted into calories and how many calories it will take to raise a specific amount of lead 1°C. What ever the lead temp is it will take the same amount of calories to raise it 1°C. So I'd say it is dependent on your lead pot and how the thermostat is working depending on the temp of the pot when plugged in. Quote Link to comment Share on other sites More sharing options...
BLT Posted February 17, 2011 Report Share Posted February 17, 2011 Someone told me one time that room temp water will freeze faster for ice cubes than filling the tray with cold water. I know it's backwards from your question, but.......never tried it. Could it be the heat to the cold molecules would stimulate them faster then warm ones, causing a faster reaction? I think I explained that right lol. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted February 17, 2011 Report Share Posted February 17, 2011 Someone told me one time that room temp water will freeze faster for ice cubes than filling the tray with cold water. I know it's backwards from your question, but.......never tried it. Could it be the heat to the cold molecules would stimulate them faster then warm ones, causing a faster reaction? I think I explained that right lol. That just does not make sense, as at some point the warm water will reach the temperature of the cold water and time would have elapsed. What your friend was saying is that warm water cools faster than cold water, but as the water cools the rate of cooling slows down. A good analogy to picture what is happening, is a tank of water. Pull the plug and the water spouts out very fast, but as the level of water drops, the flow rate reduces. The head of water determines the flow rate. It is the same in cooling, it is the temperature difference between the cooling elements and the water that determines the cooling rate. Dave Quote Link to comment Share on other sites More sharing options...
BLT Posted February 17, 2011 Report Share Posted February 17, 2011 (edited) That just does not make sense, as at some point the warm water will reach the temperature of the cold water and time would have elapsed. What your friend was saying is that warm water cools faster than cold water, but as the water cools the rate of cooling slows down. A good analogy to picture what is happening, is a tank of water. Pull the plug and the water spouts out very fast, but as the level of water drops, the flow rate reduces. The head of water determines the flow rate. It is the same in cooling, it is the temperature difference between the cooling elements and the water that determines the cooling rate. Dave Lol, didn't say I agree with him, just what he said. Trying to reason C-mans experience and what he is seeing happen. Ok, just did a quick Google search and it would seem that person is NOT wrong, warm water can and does freeze first in several test. Typed in Google "which freezes first, warm or cold water" and got many hits saying so. Edited February 17, 2011 by BLT Quote Link to comment Share on other sites More sharing options...
DUCBOS Posted February 22, 2011 Report Share Posted February 22, 2011 You have it The energy comes form the difference in temperature. I found this out working with heart surgery and ice water baths for coolong patients in the 60"s. It is the difference in temperture that causes more energy to be expanded to the cooler or warmer object. DUCBOS Quote Link to comment Share on other sites More sharing options...
Oldfart9999 Posted February 25, 2011 Report Share Posted February 25, 2011 Mayhaps we are pondering the unponderable?lol I wouldn't worry about it , just go with it, but that's because I don't have enough brain cells left to waste.lol Rodney Quote Link to comment Share on other sites More sharing options...
dlaery Posted February 25, 2011 Report Share Posted February 25, 2011 (edited) OK, when I first read this I thought of what I thought I learned in school about warm water would freeze faster than cold water.(edit) After doing some Goggle Time (GT) Yea I think it may have said that in about a zillion words. I think it has to do with the location of the "t-stat" (Glossary?) since it is measuring the temp of the pot which is about 1" away from the pot. Anyway, I have done a little experiment. I have a propane burner on my lead pot, 160 lbs. I usually leave the pilot light on so it will warm up faster, ? The propane burner is in the bottom of the pot, the pot has about a 1 inch air space around it. It has a thermocouple probe in the lead and an electronic controller. Here are the results for today: Room Temp---------46----------44----------44----------45 Lead Pot Temp---258--------467---------606--------796 Time-----------------7:06--------7:18--------7:28--------7:38 Temp is F (Fahrenheit) Today I will turn off the pilot light and shut my furnace off so things will be cold in the morning and will do the same thing tomorrow to see what happens. Edited February 25, 2011 by dlaery Quote Link to comment Share on other sites More sharing options...
