cutting the sprue

[justafeedboy]

I was casting some balls the other day, and tried to keep the same routine during the casting process. Is there a correct time to cut the sprue, I was waiting for the lead to solidify, change color, and I cut. About 15 seconds. Is this enough time? On occasion I noticed a different grain structure when I got out of my routine. I culled the wrinkled few, and am going to remelt the light ones. Thanks for your thoughts

 

[Bill Hall]

You can open the sprue cutter as soon as the puddle over the sprue is solid. Waiting longer is just letting the mold cool. Once the lead is solid, it's not going to change in any way. I assume what you are seeing on the outside of the ball is heat discoloration, not grain structure. This color will vary with the heat of the lead. The variance in color you are seeing is probably due to different time durations between pours.

I like to pour the lead until it makes a puddle over the sprue hole, then slightly wiggle the mold until the puddle stops moving, then open the sprue cutter. I gauge the heat of the lead and mold mostly by how long the puddle stays molten, 4-5 seconds is what I'm looking for.

A word of caution about wiggling the mold: If you shake it too much, you will lose some lead from the puddle, then as the lead cools, it will shrink down into the sprue hole and you could end up with a hole in the sprue of the ball. Bill

 

[necchi]

snow covered it pretty good, even 5 seconds is kinda long, that's running the mold hot, but that can be good with pure lead.

Keep practicing feedboy, it's just about finding that rythme, sometimes the tuff part is keeping it up for that 100+ session. I usually cull about 15% or so even after the temps up. That's the neat part, you can be as fussy or casual as you want,, just melt'm down an make more, :wink:

 

[Bill Hall]

Necchi, I figured someone would take notice to the 5 seconds, cuz I do tend to run the lead really hot. It's the best way I found to get rid of any wrinkles on .58 and bigger. Plus, I like the pretty purple stripes it leaves. :rotf: Bill

 

[BrownBear]

Along the lines of what the others are saying, I wait till I see the dimple form in the puddle, then swing the plate. Any longer is just letting things cool, and if you swing before the dimple forms you're angling for voids.

On molds without sprue plates, I just dump the balls once the puddle hardens, then go back and clip sprues when it's time to refill the pot.

One neat thing I figgered out for small balls and any others with short sprues. I spent $3.99 at the auto store for a cheap pair of side cutters- you know the ones in the bin by the cash register. Then I ground the jaws a little "flatter" and got rid of the bevel on the outside of the edge so I could reach into small places easier and cut the sprue off pretty near flush with the ball. Sorry for the lousy explanation of a cheap trick that works well.

 

[ohio ramrod]

Before I retired as a tool and die maker I made several "sprue cutters" by taking the side cutters and grinding in the proper radius for the calibers. They work quite well at removing the sprues with little irregularity. :hmm:

 

[justafeedboy]

Thanks for the input I can speed up the process a little. Its alot of fun learning by doing

 

[majg1234]

to get rid of the sprue thingy I'll run the lot in a small lyman brass tumbler without media a while then they come out all rounded no sprue @ all

 

[HOGGHEAD]

IMO 15 seconds is far too long to wait. 3 or 4 seconds is more than enough(for the entire process of pouring and cutting).

I cast to a cadence. It works very well. Just stat counting at a constant rate and make sure you do the exact same movement everytime at whatever number you are at in your cadence.

Casting good bullets and round balls is simple. Consistency is KING. Start yourself a cadence and stay with that cadence. Your casting will improve greatly. Tom.

 

[BrownBear]

That's a great point about cadence. It makes a huge difference in consistency. :thumbsup: