ladle technique

[hornetguy]

I tried the search function, but didn't come up with any meaningful discussions on this, so...
Since I tried ladle casting for the first time last night, with somewhat mixed results, I thought I'd get opinions and advice from all you experienced ladle guys (and/or gals)
What is your technique? Hold the spout of the (RCBS) ladle up against the sprue plate, then roll it over?
Pour from a varying distance above the sprue plate? Which seems to me to be very similar to using a bottom spout furnace...
I had several recurring problems... base not filling out completely.
"orange peel" appearance on one side or the other of the boolit.

The boolits seemed to come out with a much better surface finish (aside from the occasional orange peel)... but the bases just weren't filling out as consistently as with the bottom pour.
I was using WW metal, at about 675, with an RCBS thermometer.
I know I have a lot more experimenting to do... I just thought I'd see if there was a consensus on technique.. might save me some time.

[NVcurmudgeon]

hornetguy, I start with the ladle in my off hand. First move is to use the handy fin on the bottom of the RCBS ladle to rake any floating dross toward me, leaving a clean area to dip from. Depending on what the mould prefers, I may turn the mould sideways, connect the ladle, upright the mould for filling, then lift the ladle slightly to insure a good puddle of sprue. While the sprue is freezing, I lay the ladle down and move the mould to the off hand. I then pick up the small, rawhide hammer, cut the sprue and keep the hammer in my strong hand in case a boolit doesn't want to drop. Upon dropping the boolit(s) I lay the hammer down and switch the mould back to the strong hand. Now I am ready to pick up the ladle in my off hand and repeat. Actually most of my moulds prefer what I call the "slop pour" method. I do exactly as above, but keep the mould level, and roll the ladle into position maybe 1/4" to 1" above the sprue hole. Again I make sure to pour a generous sprue. Casting is just as much art as science. Depending on mould material, alloy temperature, mould temperature, which alloy, and probably moon phase you must experiment until the mould rewards you by making good boolits. Experiment with pouring technique, alloy temperature, rhythm of filling the mould, and length of wait before sprue cutting. To maintain as uniform a temperature as possible, I keep a parade of ingots near the heat source moving toward it. I add a one lb. ingot and usually a little bit of sprue about every 15-20 fillings of the mould. (My pot hold 12 lbs. of alloy.) While adding metal, the mould is kept close to the heat source with a boolit, or boolits in it. All of this on behalf of maintaining a uniform temperature. You must experiment to find what that temperature is. Most of my casting is done at 675 to 750 F. There is nothing magic about that temperature, but it is what works with my technique. Most of my castings are frosted, which in itself is not harmful. If you get what appears to be frosting on one side of one band that band will probably not be filled out and the boolit will appear to be bent, if it is a long rifle boolit. This is a symptome of too high a mould temperature I address this problem by slowing down the pace of casting and/or lowering the temperature of my heat source a little. Bases not filling out can be mould temperature too low. Try raising the temperature and/or increasing the pace of casting. Another culprit in bases not filling can be a tin-poor ally. My standard alloy is wheelweights plus 2% tin, which amounts to 140 gr. of lead-free solder added when I add a one lb. ingot.

[Bass Ackward]

The boolits seemed to come out with a much better surface finish (aside from the occasional orange peel)... but the bases just weren't filling out as consistently as with the bottom pour.
I was using WW metal, at about 675, with an RCBS thermometer.


Hornetguy,

When you bottom pour, a lot of air is able to escape from the hole in the sprue plate. When you laddle, you plug this vent. Everything must then escape through the blocks. So you may want to check your venting especially at the top of the blocks. Might be as simple as losening your plate. Or you might have to lightly stone a small bevel on each half of the blocks if you want to use straight WW.

Another thing that may help is to raise your temp to about 750 degrees if you want to stay with WW. Or stay at 675 and add some tin. Either way, your mix will stay molten longer and allow more time for air to escape better. Then no action to the blocks may be required. Always options.

[montana_charlie]

You know it only takes a moment for the cavity to fill up with molten lead, so there's really no reason the leave the mould and dipper mated together for very long, in my opinion.

I mate them with the mould held sideways, but that is just to get started without spillage.

To go from sideways to straight up doesn't take (me) more than a second, at which point I immediately start cracking the joint open to allow excess lead in the dipper to spill back into the pot. I do try to time it so a nice thick puddle is left on the sprue plate when the dipper is empty enough to take it away from the mould.

By cracking that joint early, air is allowed to escape...and it takes pressure off of the sprue plate so it is not held tightly down on the top of the mould. My plate is adjusted so it is fairly loose, so hot air can force it's way out from under it.
That helps with the base fill to leave a sharp corner.

If that isn't enough release for the air, Bass already mentioned the stoning of the block edges.
CM

[Jack Stanley]

The only one I have to ladle for is my twenty-two mold . It just doesn't like bottom pour . With the ladle , I put the ladle against the sprue plate and rotate it . When it's upright it gets a one count and then I break it away and leave a puddle on the plate . For the most part it works pretty well between seven hundred and seven-fifty .

Jack

[hornetguy]

ok... great ideas... I was a little concerned about the venting. I think I'll go up with the temp just a little, and try the techniques mentioned.
I read somewhere about scribing lines across the top of the mold, to create positive venting... That sounds like something that might help.
I think if I can make this work, I will probably invest in a 20# Lee melter. It would be a whole lot more efficient using that, than the old Lyman bottom spout

[44man]

Turn up the heat!
I keep the spout tight to the sprue plate. I hold it there for about a slow count of three, can't say for sure unless I time it, but I do not remove the ladle right away. If you watch the lead in the ladle, as soon as you get it and the mold turned up, you will see the lead go down and stop. If you hold it a little longer, you will see the lead go down some more and stop again. This is when to tip away the ladle and leave a good sprue. If you cast a large boolit, you will see this real easy, smaller boolits do not take as long and you might not see it happen.
I never depend on the boolit pulling lead from the sprue to fill out, I want the boolit to pull lead from the ladle. My sprue will only get a tiny dimple from it shrinking, not the boolit shrinking.
If your sprue really sucks down and you get a big depression in it, you have not filled the mold.

[Maven]

Hornetguy, 44man's correct about the temp.: Start at 750-760 deg. F. Once you have perfectly filled out bases, gradually reduce temp. to ~700-710. Also, make sure the mold cavities are 100% free of oil, grease, or any other contaminant. If there's none, then smoke them with either a BIC lighter or wooden match. These steps ought to eliminate the problem. Lastly, some molds respond better to casting (and base fill-out) if the ladle is in contact with the mold. Others produce perfect CB's by just pouring the alloy into the cavities from a given height, e.g., 1/8"- 1/4" above it. You'll learn from experience which works better for your particluar mold(s). Hope this helps!