Author Topic: casting ??? (Read 592 times)

Good time Charlie · « **on:** December 14, 2003, 02:17:56 AM »

I am new at this but love it when it is working right. When I start casting my bullets look amd are great. But after awhile they start coming out blue looking and are not good looking bullets. It seems if I add more lead and flux again it straghtens out. What is going on?
Charlie

wener · « **Reply #1 on:** December 14, 2003, 05:46:22 AM »

after about a half hour to 45mins. or so the allows tends to seperate some! fluxing brings back the allows depending on the temp. you are running. so depending on the the bullet you are casting, and begining with a full pot, fluxing at the start and about 30 min.s in! your bullets will stay more consistant.

LAH · « **Reply #2 on:** December 14, 2003, 07:40:54 AM »

I agree, try fluxing on the half hour.

Calamity Jake · « **Reply #3 on:** December 14, 2003, 10:21:53 AM »

Charley, If you casting with pure lead or something close, high casting temps will cause the alloy to turn blue in color so when you add alloy and flux you are lowering the temp which makes things right again.
Lower the casting temp and see if that will help.

Some beleave that lead alloys will seperate (no flames intended) but that's not ture. What looks like seperation is oxidation of the surface with oxygen in the air.

If you are using a bottom pour pot you can elimanate oxidation by putting a 1/4 in. layer of the cheapest clay cat litter you can find at the G store on top of the melt. It also helps hold in heat.

The next time you fire up the pot, flux good, add cat litter, you will never have to flux again. When you add sprus in just lay then on top of the CL they will melt and run thru fluxing along the way.

The CL will break down and turn to dust aftet 4-5 casting sessions, just scoop it off and throw it in a coffee can to cool, add new and discard the old.

If you are ladle casting, forget the CL and flux every 30-45 min.

Calamity Jake

Lloyd Smale · « **Reply #4 on:** December 14, 2003, 12:22:05 PM »

got to agree I flux when I start and thats it even when i add metal i find little need to flux.

LAH · « **Reply #5 on:** December 14, 2003, 02:48:42 PM »

Calamity Jake is correct in that too high tempature will cause pure or near pure lead to display a blue color. Adding alloy would cool the melt and make the color disappear. I checked some pure lead ignots we poured sometime back and they were blue colored. These were processed on a propane burner with a 2 gallon cast iron pot. We were rushing and had the fire much to hot.

As for the oxidation on top the melt, I thought it to be tin? Our 40 and 100 pound pots start to display this oxidation after 20 min. or so. Fluxing turns the melt sliver color again and leaves nothing to skim so I assume it returns to the melt?

Melt caps can be used but I'd just as soon flux. When I was hobby casting I used a cap of sawdust which I also fluxed with. It's works fine but it adds to waste that must be disposed of. The flux we use not only returns the tin to the mix, but also removes stuff that shouldn't be there. Even though we use foundery metal our waste runs 19 to 20 pounds per 1500 pounds of alloy. It adds up in a hurry.

And BTW...Hello Lloyd