Foto Joe
08-10-2013, 09:18 AM
Yesterday morning while getting my "Honey Do's" finished up I flipped the switch on my lead pot and stuck some COWW ingots in to let her warm up. Once things got melted I fluxed (paraffin) then stuck my dipper in the pot and set my Lee 214SWC mold across the top to warm up. Since I've been using the same temp setting on the pot for quite a while with good success I didn't put the thermometer into the pot. The setting I use typically will start out at about 700 and then cool off to 650+/- a little while I'm casting which seems to work pretty good. But yesterday I got side tracked with another Honey Do and delayed about twenty minutes getting back to the shop. When I gloved up and grabbed the mold I noticed that there was an unusual bluish tint on the top of the melt which pretty much told me things were a bit warmer than usual so I stuck the thermometer in to have a look see, almost 800 degrees, YIKES!!
On the plus side the mold was warmed up nicely and my second cast gave me purty boolits, the downside was that only lasted for about three casts and things got strange, fins on both top and sides. Obviously the temp was way too hot so I turned it down and started dropping the sprues and boolits into the pie tin I keep in front of the pot, once they cool a bit I dropped them back into the pot to cool it off and of course things started getting much better once the temp dropped to between 700 and 750 degrees but here's where the epiphany comes in....
I decided to let the pot keep cooling off and see what happened. As the temp dropped below 650 thing were still going along fine, at 615 degrees I was able to actually pick up the pace of my casting instead of having to wait for things to cool off before nipping the sprues and the boolits were dropping very nicely, some of the best I've cast in my short, short career casting boolits. When the temp hit 600 degrees it was like a light switch got flipped though, I started getting poor fill-out every other cast and after a half dozen to make sure that it wasn't my own ineptness causing the poor fill-out I popped the temp back up a touch. Once it hit 610 degrees all was well again so I finished out between 610 and 625 degrees.
For those of you who have been casting since well into the last century this might seem like a very elementary observation but it's one of those things that I thought might just help somebody who is newer to the craft. Granted this was using a Lee aluminum mold and an iron mold would more than likely not appreciate such a low casting temp, also I'm quite sure that each thermometer has it's own unique calibration and I don't expect that my Lyman one is the most accurate so somebody else's mileage may vary.
On the plus side the mold was warmed up nicely and my second cast gave me purty boolits, the downside was that only lasted for about three casts and things got strange, fins on both top and sides. Obviously the temp was way too hot so I turned it down and started dropping the sprues and boolits into the pie tin I keep in front of the pot, once they cool a bit I dropped them back into the pot to cool it off and of course things started getting much better once the temp dropped to between 700 and 750 degrees but here's where the epiphany comes in....
I decided to let the pot keep cooling off and see what happened. As the temp dropped below 650 thing were still going along fine, at 615 degrees I was able to actually pick up the pace of my casting instead of having to wait for things to cool off before nipping the sprues and the boolits were dropping very nicely, some of the best I've cast in my short, short career casting boolits. When the temp hit 600 degrees it was like a light switch got flipped though, I started getting poor fill-out every other cast and after a half dozen to make sure that it wasn't my own ineptness causing the poor fill-out I popped the temp back up a touch. Once it hit 610 degrees all was well again so I finished out between 610 and 625 degrees.
For those of you who have been casting since well into the last century this might seem like a very elementary observation but it's one of those things that I thought might just help somebody who is newer to the craft. Granted this was using a Lee aluminum mold and an iron mold would more than likely not appreciate such a low casting temp, also I'm quite sure that each thermometer has it's own unique calibration and I don't expect that my Lyman one is the most accurate so somebody else's mileage may vary.