Bad casting... :(

[MKT]

On my last pour I will leave the bullets in the mold but I do knock off the sprue. Same reason, to try to keep the cavities clean.

 

[Skip Sackett]

I leave bullets in, sprue intact and hose that puppy down with WD-40. Yes, it gets on the inside BUT, I scrub my moulds with super hot water and Dawn dishwashing soap before a casting session. I do this while the melt is getting hot so I am preoccupied! Then, I heat them on the kitchen stove, for just a bit to make the dry, not hot, but dry, then to the top of the pot until the melt is finished coming to temp.

Aluminum moulds get a corner into the melt for a few minutes. They dissipate heat more so the need to be hotter to start with. If they get too hot while casting, I have a folded work towel in a plastic coffee can lid (turned upside down so there is a slight "bowl" affect) saturated with water that I touch the mould to to dissipate more heat.

The mould has to be up to temp first and full when you do it though OR you can get water in the cavities. That combined with molten metal is not a good thing!

 

[CookE]

As far as dipping iron molds in hot lead, just be sure you fill the mold first and leave the sprue on top. Then you can dip them if you like and you shouldn't have any trouble. The best way is just fill it, leave the sprue on and set the molds on top of the pot for a little while till they are hot. Then before you start to cast take about 3 kitchen wooden matches, put them together and light them. Then use them to smoke, "blacken" the interior of your molds. You will be surprised at how easy and perfect the bullets will come out of the molds. Make sure you get both interiors of the molds a nice dark smoked black. Do that on the top of the sprue plate also. Don't do it on the bottom of the sprue plate or on top of the mold where the sprue plate slides back and forth.......ONE THING YOU "NEVER" WANT TO DO IS TAKE A FULL MOLD WITH THE SPRUE ON TOP AND "DIP IT IN A BUCKET OF WATER" TO COOL IT OFF. I CAN ASSURE YOU, YOU WILL BE BUYING NEW MOLDS...I would like to say I heard of someone doing this, but I had first hand experience. I had an "oldtimer" tell me they used to do this all the time and never have any trouble, well let me tell you, YOU WILL WARP YOUR $150.00 MOLDS IF YOU TRY THIS METHOD. I hope that little hint will make your casting much easier.........CookE

 

[papajohn428]

Here's another tip for you..............make sure the mold is actually closed before you fill it.