brass mold tinning

[Bushrat]

I was using a nearly new brass mold that belongs to my friend. It made nice boolits but I had a few small places where the lead stuck to the brass and has bonded. How can I get it off and how do you keep it from happening again.

[bangerjim]

Is it bright and shiny or a rich deep golden color when you started using it? All brass molds need to be seasoned 3X to around 450F to oxidize the brass from new & shiny to that golden oxidized color.

I have 4 brass molds, seasoned them properly, and never any tinning!

Heat the mold to FULL CASTING TEMP (450-500F) on a hot plate and then take a hardwood dowel and scrape the lead off as best you can. After clean, season it again.

Make sure your mold is clean of anything that will act as a flux when casting again.

bangerjim

[Bushrat]

Thanks, I will give it a try, not my mold but I know it has been used before.

[303Guy]

Remember that some waxes are fluxes that will cause tinning. Like stearic acid, found in lanolin.

[country gent]

Heat the mould slowly and evenly to where the tinned lead softens a bamboo skewer ( sold in most grocery stores) works well clean the end to square and fairly sharp corner when mould is hot use this to work the lead out. Sometimes a little 2 cycle oil or dish soap will help raise it and loosen it also. If using hte oil or soap do it outside with good ventilation as there will be smoke.

[Leadmelter]

I had a little on one of mine and I used a single edge razor blade to take off a few specs.
Leadmelter
MI

[PbHurler]

Here's a "sticky" about this:

http://castboolits.gunloads.com/showthread.php?213156-Lead-Adhearing-to-Mould

[44man]

Interesting thing about boolit lubes and getting any in a mold. I made a test on brass with every boolit lube and a soldering iron. ALL were a great flux.