Casted my first boolits last night

[Wyatt1]

I'm thinking I may have zinc contamination...

The pistol boolits (9mm Lee mould and .44 RCBS mould) practically all came out with lines, rounded lube rings and incomplete fills. About half of the 30 cal boolits RCBS mould)came out okay.These were cast last in the session. Not sure if it was because the lead was super hot or because we got the process down. All boolits were heavier than the mould advertised. 150 g 30 cal weight 159g consistently. Fluxing with linseed/ paraffin/ vaseline mix).

I'm guessing I need to clean my lee production pot really well (it's very cruddy)and actually get a thermometer.Good place to start?

Thanks from Maine

[Powellcole5490]

Wyatt1,

Well I can only tell you, from my experience when I first casted bullets I dumped my bullets back into the pot several times so I could practice getting the process down. My first casting session only produced maybe 100-200 useable bullets and it took me 4+ hours but the experience was priceless. I've since cast a few more times and it's like "butta". Every one comes out perfect. Did you melt your lead down into ingots? If so, what temperature did you melt them in? Since you said you don't have a thermometer, I would HIGHLY suggest getting the RCBS thermometer. If your pot is running over 700 degrees you may end up with a zinc issue. That may not be your problem though. Maybe your mold was too cold/too hot, maybe your alloy was too cold. The more variables you can nail down the better. Until then practice, practice, practice!!!

[462]

Howdy, Wyatt.

Wrinkled boolits have nohing to do with pot temperature. They are caused by a mould that has not had all the machining fluids removed, has not reached its optimum casting temperature, or a combination of the two.

Thoroughly! clean mould and pre-heat the mould. Do a short casting session (100 boolits?) and stop. Go through the same procedure the next day, and till the mould comes right.

I've found a thermometer to be a useful casting tool, but excellent boolits can be produced without one. All you need, for that, is a clean mould that has been pre-heated to the point where the first cast results in keeper boolits.

Advertized boolit weight and reality rarely equate.

A pot should be clean so that impurities don't contaminate the alloy and boolits, but a dirty pot won't cause wrinkled boolits.

[Willee]

I'm thinking I may have zinc contamination...

The pistol boolits (9mm Lee mold and .44 RCBS mold) practically all came out with lines, rounded lube rings and incomplete fills.

Thanks from Maine

Being new to casting myself I also have had this problem.

I clean the mold with One Shot cleaner and dry lube letting the stuff dry in the mold.
All the boolits that first come out of the cold mold are wrinkled.
I have placed the mold on the gas stove and heat it until it stops smoking.
Once the mold gets up to temp the boolits start coming out nice.

Also if you are filling the cavity to slowly wrinkles can happen.

Willee
Corpus Christi Texas

[Sloffie]

I just cleaned my Lyman mold thoroughly with some mentholated spirits and got out all the oil. I then started casting and after a few casts the mold was nice and hot and all the bullets came out beautiful. This was for my Muzzle Loader so I used pure lead.

[David2011]

Wyatt,
I agree completely with what 462 said.

Congrats on your first casting session! Since your boolits came out heavier than expected it's unlikely you have zinc contamination. Zinc is less dense than lead and would make your boolits lighter than expected. My boolits are almost always heavier than the designated weight.

While Lee molds will produce excellent boolits, they are hard to use. The aluminum loses heat very quickly necessitating a hot melt and a fast casting rhythm. Cast iron and steel molds hold heat much better and are easier to use.

Your pot should be reasonably clean but the mold has to be completely free of manufacturing oils and contamination. Contamination in the casting pot normally either burns off or floats to the top and can be skimmed off. Contamination in the mold will cause defects in the boolits. A cold mold will cause rounded corners and incomplete fill and can be one reason for boolits having a wrinkled appearance.

You're probably not running too hot. Boolits that are cast too hot will have good fill and clean edges but will have a dull, frosted appearance. Correct temp will yield shiny to slightly frosted appearance. It used to take me anywhere from 20 to 40 casts to get the mold up to temp. At the recommendation of others on this forum I bought a $10 hot plate at a drug store to pre-heat the mold. It reduced the number of bad casts considerably and will keep the mold hot if you have to pause for a bit.

Now that I have a thermometer I use it every time I heat up the pot but I cast plenty without one. The major factors for your mold temperature are the temp of the melt and the speed and rhythm of the casting process. Try to keep your speed consistent and the mold will stay at a more even temperature. Try to get each portion of the casting cycle to take the same amount of time, every cast. If the mold gets too hot or cools down, try changing the speed of the casting cycle. You can also raise or lower the temperature of the melt but that will take a while to change. Changing the time between casts will have an effect much faster. As the melt temp gets to where it needs to be you will be able to cast at an optimum speed (as fast as you want is optimum IMO.)

The thermometer is really useful when you smelt your raw metals. If you keep the melt at about 650 degrees F, zinc won’t melt. It just floats to the top and can be skimmed off. (You’re not smelting wheelweights and other metal in the production pot, are you?) There are tons of threads on smelting available here.

Keep trying. You will learn quickly.

David

[runfiverun]

dip the corner of the mold in the alloy till the lead doesn't stick to it.
then start casting.
the others have pointed out the oil in the new mold issue.
once you get the mold up to temp you can increase or decrease your speed or alloy temp to maintain the boolits appearance,you can also use the time it takes for the sprue to cool to guage whats happening.
the aluminum molds temp and cadence will be different than your rcbs mold.

[bowfin]

Fluxing with linseed/ paraffin/ vaseline mix

A lot of us flux with sawdust. The above sounds almost like a lube, rather than a flux.

[doctorggg]

As a newbie to casting I have been using natural pine pet bedding for fluxing. I currently do not have any sawdust that isn't treated and unsafe. Does this work ok? It seems to be wroking for me.
Thanks for the answers in advance.

[trixter]

Is the Pine Pet Bedding just sawdust, or has there been something added?

I go around to some of the cabinet shops in my area and ask them for a gallon (Coffee can) full. I'm kind of fussy though I like 'Ponderosa Pine', but will settle for whatever they offer.

[Cherokee]

You have some good advice so I'll just say Welcome. It takes some time to learn but the mould must be clean & hot.

[doctorggg]

The pet bedding is large flakes of cut pine. Nothing else added. All natural. It takes a handful and it stays in place and burns slowly. It leaves a black charred dust on the lead.

[doctorggg]

Sorry if I am cutting in on this thread. Since the subject of fluxing with sawdust came up I thought I would ask. I am not sure of the proper protocol yet.

[canyon-ghost]

Sawdust and wood work good in a bottom pour pot. If you are fluxing with parafin, use it all by itself. I use candle wax for a ladle pot. When the white smoke gets to be too much, I light it (watch those foot high orange flames, it's really flammable!)

When it burns down, all you have is a black film on the surface to skim off. It works very well, considering the amount of hydrocarbons it contains.