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runfiverun
10-12-2008, 12:48 AM
my 20 year old lee was giving me some grief today.
and while i had the thermometer out and was messing with the contacts i looked at my stack of ingots and seen that i had several broken and different sized ingots there.
so i got the lee stabilized to temperature and decided to weigh some of the chunks of ww ingots.

by now you are saying so-what......

so i got to wondering how much dropping those different sized pieces in would lower my melt temp.
here are the results.
a 5oz piece of ingot dropped the temp by just over 5* [about the size of a good sprue puddle.]
an 8 oz piece dropped the temp by 20*
a 10 oz piece lowered it 30*
a 12 oz piece lowered it by 35*
and a 1 lb [average ingot size ] i had to weigh a few till i hit an exact 16 oz.
this dropped the temp by 50*
the recovery times seemed to be near the same till the 16 oz ingot then it took near 30 seconds or about the time it might take to make 2 drops/pours.
thought you may find this interesting.

montana_charlie
10-12-2008, 03:20 PM
i had several broken and different sized ingots there.
I would be interested to learn how you ended up with broken ingots.
CM

mooman76
10-12-2008, 07:28 PM
I am interested because I don't have a thermometer and have wondered but you didn't say what size pot. I usually crank my heat up just before I drop a 1# ingot in and then turn it back down a couple minutes later when I think it is back to temp.

runfiverun
10-13-2008, 08:23 AM
the standard 20 lb lee.
charlie: they were broken cause i get impatient when smelting and just dump them out while hot.
i weigh my lead when casting so i know how much i run or when adding tin.

mooman76
10-13-2008, 08:34 PM
Thanks for the info Runfiverun. Always looking to learn something. Sometimes the littlest piece of info can can help allot.

Boerrancher
10-14-2008, 04:02 PM
I never add material to the pot while I am casting. When I run out of alloy or am finished for the session I will add material, flux and then unplug the pot. I don't have a thermometer, I cast this way to keep my temp the same. I am not tough enough any more to cast up 20lbs of boolits at a setting, so the pot never gets empty with a casting session. Also, thank you Rfr for the info it just proves what I have thought all these years, with the exception of the recovery time, which I had suspected to be longer. Years ago while I was learning to cast The old Lyman pot when you dropped a 1 lb ingot in it, you had better have something to do for about 15 min, because it was going to be that long before the alloy would run out the bottom spout. My Lee does not have that slow of a recovery time.

Best wishes from the Boer ranch,

Joe

shotman
10-14-2008, 05:38 PM
i see some of you do a water drop. that is fine but if you have a small void and drop back a boolit it will explode . I have run a hardnest test on a water drop and a air cool I cant tell more than 2 sets on tester. To me its not worth the danger rick

felix
10-14-2008, 06:09 PM
Will not explode when the hole stays the same dimension as before being dropped. So, dropping in water is entirely safe. Dropping boolits back into the pot, after being dropped in water can be dangerous. No reason to do so, because it is always best to finish the pot before adding anything back to it. ... felix

Springfield
10-14-2008, 06:35 PM
I add every sprue back to the pot as I cast. I did this when I ran a LEE/RCBS as it kept the pot fuller and I didn't have to add ingots so often. I generally will empty the pot a couple times in a session, as in I cast abut 60-80 lbs in a session. I used to have to use 2- 20 lb pots, and fill the one in use with the one just melting lead. Now I use a 1500 watt pot and don't have that problem anymore.

mike in co
10-14-2008, 07:21 PM
re do the test.
this time put the partial pcs on the edge of the pot for 10 min or so, then add...and see what happens.
i typically have 7-8 lbs preheating on the top of my rcbs pot. move from the back to the front, and then into the pot aprox 1.2 lbs at a time, alternating returning sprues.

mike in co

Ricochet
10-14-2008, 07:37 PM
I drop sprues and rejects back in while casting, but anything water dropped doesn't go back into the pot until the cooling metal has solidified. If I see base defects when the sprue plate is swung, they go back into the scrap pot to dump back into the melt, not into the water.

montana_charlie
10-14-2008, 09:23 PM
When I pour a bullet and lay the dipper back on the melt, the previous bullet, and it's sprue, are laying (by themselves) on a terrycloth inspection pad.
While the new one 'gestates', I use a teaspoon to return the previous sprue to the pot. I also use the spoon to roll the bullet around for a visual inspection. The spoon is then used to return the bullet to the pot...or to a different pad with the rest of the 'keepers'.
By this time, the new bullet is ready to 'be born' and dropped on the inspection pad.

This speed/rythmn results in close monitoring of visual quality, and is leisurely and satisfying.
Both of the moulds I use (most frquently) work well at this rate.

The sprues and bullets going back into the pot are very hot, and if they decrease the overall melt temperature it's not enough to register on the thermometer.

After I have enough keepers to equal 10% more bullets than I started out to make, I fill the pot almost full with new alloy. While it is coming up to temperature, I re-inspect the keepers...but under magnification, this time. I go slowly so that the newest ones will be cool enough to handle by the time their turn comes. Any that fail this close inspection go into the pot, along with any from the last loading session that got rejected after being weighed.

When the pot is back at casting temperature, I turn it off and reduce any oxides. The pot cools while I clean up the casting area, and I monitor the thermometer to make see if the alloy solidifies at (close to) the expected temperature.

I only recommend my method for those who are super picky about their bullets...and who want casting to be a relaxing process.

Yes, I am guilty of dropping lead in my pot...but not guilty of dropping pot in my lead.
CM

Ricochet
10-14-2008, 10:53 PM
Yes, I am guilty of dropping lead in my pot...but not guilty of dropping pot in my lead.
Bet that'd make a pretty good flux.