Casting temp

[holsterguy]

Just got a new mold from Accurate. First castings didn't go well. Pre heated on a hot plate while pot was melting. (Mold was scrubbed good with dawn and hot water prior).Lubed the spru plate pivot with 50-50 stick lube like all my other molds, and started casting. After 10 or 12 dumps, boolits are still pretty wrinkled. Lee 4/20 set on 6 1/2. Using 30-1 lead tin. As pure lead likes to be ran really hot, you think with this mix I should crank it up some, or is it something else?
TIA!!

[centershot]

If it were me, I'd ditch the 50-50 lube as sprue plate lube and switch to synthetic 2-stroke oil, you'll be happy you did! As to temp; My Lee pot will not hold any temperature reliably, swings of +/- 50 degrees were the norm. I built an inexpensive P.I.D and I'm HAPPY!!! Temp control is now +/- 3 degrees. Stop beating yourself up, get a P.I.D. Yes, your pot and/or mold, or both, are not hot enough. Your alloy is almost pure lead, it wants to cast HOT! Bump it up!

[Rcmaveric]

My experience is no matter what i clean a new mold with or how clean i got it. Ie water break free surface. It still gives me wrinkly bullets for a while. I think smoking the molds burns off impurities more than the soot acts a release. Run it hot to finnish burning off the oils. Just keep casting till the bullets are wrinkle free.

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[243winxb]

aluminum, brass, iron mold? They make all 3.

Basic. Lose the lube. Maximum heat till bullets frost. Then back off the temperature some.

[Leadmad]

I also recommend the PID control, made mine approx. a year ago and use it for pre-heating moulds, Pot temp and Temp control in my oven I use for powder coating bullets, a small investment that makes a massive difference

[holsterguy]

Thanks guys! Did pick up some full synthetic 2 stroke oil. I'll clean it again, crank up the heat and give er a whirl!

[OS OK]

Just get that mould up to 300*~350*F. before you start. Pure Pb + Sn will cast beautifully at 720*F. Generally a 20# Lee pot will maintain that temperature on a setting of 4...put your sprue cuts back into the pot when the pot is about 1/2 full, you'll notice that the Pb is not coming out of the spigot as fast as it was when the pot was full. Refill the pot and take a 10 minute break or so. At least, use a temperature gage, a thermometer to see what is actually happening.
Your trying to heat the mould to operating temp. and maintain that with the pot melt Pb temperature...also if you are not pouring directly into the center of the sprue plate holes and the sprue plate is not hot as the mould...your chilling the Pb as it enters the cavity. The sprue plate will suck the heat out of the Pb as it enters. Results are wrinkles just like oil in the cavity will cause wrinkles.
The mould needs to be hot enough to allow the cavities to be filled entirely with the Pb before the whole cavity chills and solidifies as a unit & it needs a generous sprue puddle to draw from as it shrinks.
If the hot plate is struggling to generate enough heat put something over the mold to create an oven...keep the heat all around the mould and sprue plate.
Pour generous sprues...keep the sprue plate hot also.
If the sprues are solidifying in less than 1 second your running borderline 'not hot enough' on the mould & sprue plate. Each mould has different operating characteristics depending on the size of the cavities, the number of cavities and the actual size of the mould blocks along with whether or not they are Al., steel or brass.
You just need to keep at it and watch all these variables...don't guess at temperatures.

[Hairy Dawg]

Wrinkles indicate that the mold is too cold. I will pick up the pace until the wrinkles disappear. I cast with all of my molds with a pot temp of 750. The mold temp varies, depending on which one I'm using, & it seems like each one has it's sweet spot where it casts the best. I have a steel mold that loves it around 345, and a brass one that wrinkles when the temp drops below 480.

[mehavey]

Wrinkles indicate that the mold is too cold.It also indicates residual oil in the mould.

1. Get a lead thermometer -- cast 30-1 @ ~750°-770°-ish
2. Forget "lubing the sprue plate pivot" Not only no benefit w/ steel, but absolutely introduces residual oil no matter what.
3. Put a smallest "dab" of full synthetic motor oil on a piece of 100% cotton dishtowel. Work that "dab" into the fabric like a fiend so that almost nothing remains except the baaaaaarest hint that anything is left at all.
4. As you get up to casting rhythm, open the sprue plate, but don't open the mould. Leave the bullets in the mould.
5. Scrub that cloth from #3 hard across the mould block/bullet-base surfaces; then again/scrub the bottom of the sprue plate the same way.
6. Dump the bullets at that point and proceed as usual for several dozens more castings.
7. If/when even any hint of leading between the sprue plate/mould surface starts, Repeat step #5 and press on.

[gpidaho]

An excellent lube for the hinge, sprue plate and mould top is dielectric silicon grease. I save the 2 cycle motor oil for the pins. The dielectric grease does not migrate to the cavities as other lubes do. Use it sparingly, a little bit goes a long way. Gp

[lightman]

I agree, run it a little hotter. I cast with mostly wheel weights and set the pot temperature at 735º. I prewarm the mold and adjust the mold temp by how fast I cast.

[holsterguy]

Thanks for all the tips guys, that did the trick! When we got home from church, cast a bunch of these beauties with only a few culls!219957