dipper technique help

['74 sharps]

Will be casting my first time next week using an RCBS dipper, and a two cavity 480gr mold. Any advice on getting this right would be appreciated.....

[HangFireW8]

Exciting! If you have a Sharps you obviously need to be casting!

Let's see...

Really scrub and clean the mold of all machining oils. Get a pencil or probe and run it gently from the cavity to the edges and see if it hangs up on a burr as you slide it out. If it hangs even a little, your boolits will stick. The solution is lapping the cavity not using smoke, mold release, etc.

Remove the sprue plate (there may be a second set screw holding the main screw in place) and check if it is flat. It is common for there to be proud spouts or burrs around the pour holes or at the pivot hole. It doesn't have to be perfectly flat but do lap away any burrs or really high spots. Put some lube (I use NRA 50/50) in the pivot point, but not in the screw hole, on reassembly.

With the sprue plate and handles off, check if the mold comes together correctly in all dimensions. If it wants to site crooked, or has slack when crooked, it needs to have the alignment pins adjustes. The handles cannot correct for this if it is a problem. Put a tiny amount of lube on the alignment pins (carefuly not to get it in the cavities or even on the mold face). Again I use NRA 50/50 here. Bullplate will work but won't last as long.

I do highly recommend using Bullplate according to the instructions, which is, when the mold is up to temp, and you've cast your first boolits (with filled-out bases), spread Bullplate across the top of the mold, and both sides of the sprue plate, very lightly. Re-apply ever 50 to 100 casts.

Preheat the mold before starting and leave the ladel in the melt so it is up to temp as well.

For large boolits like 480 grains I think you're going the right way with the ladel instead of bottom pour; even though I prefer bottom pour, for really large stuff the ladel works best.

Good luck and tell us how it goes.

HF

[44man]

Easy. Get your lead to temp and pre heat he mold. Flux and clean the lead, then set the dipper in to get hot.
Fill it about half full, turn the mold sideways and insert the spout of the ladle tight in the sprue plate. Rotate to vertical slowly and hold all tight together long enough for the shrinking boolit to take all the lead it needs from the ladle. If you look into the ladle you will see the lead go down, stop for a second and go down a little more, that is the time for each pour.
Now without moving the mold, tip off the ladle leaving a nice sprue.
As soon as it sets, do the same to the other cavity. Let that sprue set before cutting.
Don't get in a hurry, relax, I suppose that is the most important thing I can tell you!
Once you get the hang of it, you can empty the pot with no rejects.
I cut the sprues to fall in a big coffee can and put them back in the pot now and then, flux and keep going. I use wax to flux, it will light up and keep smoke down in the garage. Stir it in until it goes out, then clean the surface. I use an old spoon with a long wood handle riveted to the spoon handle.
Do NOT clean with the ladle, keep the spout clean by wiping it with a cotton rag now and then. You want to limit leaks at the sprue plate.
You will be surprised how productive it is. You will not need to sort, throw back rejects or weigh boolits once you get used to it.
It will get boring so you might want dancing girls on the bench!

['74 sharps]

Exciting! If you have a Sharps you obviously need to be casting!

Let's see...

Really scrub and clean the mold of all machining oils. Get a pencil or probe and run it gently from the cavity to the edges and see if it hangs up on a burr as you slide it out. If it hangs even a little, your boolits will stick. The solution is lapping the cavity not using smoke, mold release, etc.

Remove the sprue plate (there may be a second set screw holding the main screw in place) and check if it is flat. It is common for there to be proud spouts or burrs around the pour holes or at the pivot hole. It doesn't have to be perfectly flat but do lap away any burrs or really high spots. Put some lube (I use NRA 50/50) in the pivot point, but not in the screw hole, on reassembly.

With the sprue plate and handles off, check if the mold comes together correctly in all dimensions. If it wants to site crooked, or has slack when crooked, it needs to have the alignment pins adjustes. The handles cannot correct for this if it is a problem. Put a tiny amount of lube on the alignment pins (carefuly not to get it in the cavities or even on the mold face). Again I use NRA 50/50 here. Bullplate will work but won't last as long.

I do highly recommend using Bullplate according to the instructions, which is, when the mold is up to temp, and you've cast your first boolits (with filled-out bases), spread Bullplate across the top of the mold, and both sides of the sprue plate, very lightly. Re-apply ever 50 to 100 casts.

Preheat the mold before starting and leave the ladel in the melt so it is up to temp as well.

For large boolits like 480 grains I think you're going the right way with the ladel instead of bottom pour; even though I prefer bottom pour, for really large stuff the ladel works best.

Good luck and tell us how it goes.

HF

Thanks for the help. Been sort of a progression....learning reloading smokeless, switched to bp, getting the results from the bp, and now learning how to cast. Trying to punch paper @ 200yds, and then to longer distances....

['74 sharps]

Was doing some reading about borax as a flux...seems to work well for the authors..any thoughts? Thanks for the tip on two cavity casting......

[geargnasher]

Save the borate compounds for killing sugar-seeking ants, if you put it in my casting pot we're gonna rumble!

There are a couple of different compounds, sodium borate and potassium?? borate I think. They are very good at removing impure elements and oxides from your melt, but if you use it, but that's part of the problem. If you don't "reduce" your tin, lead, and/or antimony oxides back to elemental metals first (using wax or sawdust), then your borate flux will permanently bind with and remove it. In other words if you don't two-step reduce/flux, you lose valuble tin. The stuff attracts moisture, rusted my pot liner the two times I used it, and made my boolits softer. The borate glass layer must be skimmed away while still molten when you're finished casting or you'll have a royal mess on your hands.

Just use sawdust or wood shavings, stir with a stick, and be happy. If you want to know exactly why that's the absolute best way to flux, clean, and reduce a pot of boolit casting alloy, read chapter four of From ingot to target: A cast bullet guide for handgunners by Fryxell/Applegate at the LASC dot US site. Or look up CBRick in the members list and follow the link in his sig line.

Gear

[stubshaft]

Drill out the spout of he RCBS to 3/32". I use a Q-Tip and swab a light coat of Bullplate in the spout to reduce any buildup. It may take a couple of pours before you get proper fillout and the mold/sprue is read to drop good boolits. Find the casting cadence that works for your mold.

[John Boy]

Fill it about half full

Have found a full ladle works better filling out the bullets in the mold
Adds:
* With ladle spout fitted tight on the mold in the vertical position pour for 5 seconds. The create a nice sprue puddle of melt. When the sprue puddle consistently at 5 seconds, you are at the correct casting temperature
* Then cut the sprue
* Consistent rhythm is the name of the game for casting good bullets
Plus read this ... http://www.longrangebpcr.com/8Phases.htm

['74 sharps]

Save the borate compounds for killing sugar-seeking ants, if you put it in my casting pot we're gonna rumble!

There are a couple of different compounds, sodium borate and potassium?? borate I think. They are very good at removing impure elements and oxides from your melt, but if you use it, but that's part of the problem. If you don't "reduce" your tin, lead, and/or antimony oxides back to elemental metals first (using wax or sawdust), then your borate flux will permanently bind with and remove it. In other words if you don't two-step reduce/flux, you lose valuble tin. The stuff attracts moisture, rusted my pot liner the two times I used it, and made my boolits softer. The borate glass layer must be skimmed away while still molten when you're finished casting or you'll have a royal mess on your hands.

Just use sawdust or wood shavings, stir with a stick, and be happy. If you want to know exactly why that's the absolute best way to flux, clean, and reduce a pot of boolit casting alloy, read chapter four of From ingot to target: A cast bullet guide for handgunners by Fryxell/Applegate at the LASC dot US site. Or look up CBRick in the members list and follow the link in his sig line.

Gear

Will do, I have plenty of oak sawdust. Next question, how much and how often? Am using 20-1 from Rotometals in a Lee 20# pot.

[montana_charlie]

Put some lube (I use NRA 50/50) in the pivot point, but not in the screw hole, on reassembly.

I do highly recommend using Bullplate according to the instructions, which is, when the mold is up to temp, and you've cast your first boolits (with filled-out bases), spread Bullplate across the top of the mold, and both sides of the sprue plate, very lightly.

A wax-based 'lube' may be just the ticket for an object passing through a bore at 2500 fps, but it is NOT a 'lubricant' in the sense of preventing wear between two permanetly joined metal surfaces.

Actually, although it is intended to keep lead from sticking to a mould, Bullplate is a better 'lubricant' at a pivot point than NRA 50/50 ... or any other concoction containing wax.

CM

[GLL]

I agree with stubshaft abut drilling out the spout on an RCBS ladle ! It improves alloy flow considerably.

Jerry

[geargnasher]

Will do, I have plenty of oak sawdust. Next question, how much and how often? Am using 20-1 from Rotometals in a Lee 20# pot.

If you're using certified alloy, the anwer might be "not very much or very often" since there shouldn't be any impurites to worry about. If you're ladling, just use a tablespoon or so when you get the pot filled and all melted, and stir it around with a DRY wood stick like a paint mixing stick. Let the stick char some, and light the smoke if you can. Once the surface is all shiny with charred sawdust and a little ash on it, go ahead and skim if you want to. Ladling exposes lots of the alloy repeatedly to air and tends to build a tin-rich oxide scum very quickly, so if you can get comfortable with it, it's a good idea to ladle through the charring sawdust so it will keep your tin "reduced" while you cast and protect the surface from further oxidation while you cast.

Whatever you do, don't just skim the oxides and throw it away, because it doesn't take long for 20:1 to become 30:1 and so on. Keeping your pot temperature to about 100 degrees over the melt point of the alloy and NOT overheating it reduces the oxide drossing dramatically.

Gear

[stubshaft]

I would have to disagree with John Boy and NOT hold the ladle tightly against the sprue plate. This is how you would pressure pour and if the mold and alloy is at the right temperature it is not needed. Pressure pouring in itself can cause a gamut of problems.

[canyon-ghost]

I use candle wax or parafin to flux, you can even buy Gulf canning wax in grocery stores. It's all parafin. Parafin is really flammable, foot high orange flames when you light it.

My thoughts are to keep the dross off the top of your melt, flux and skim, and skim, and skim. If you get dross, that floats into your ladle, it tries to block the flow with stringy streams that barely pour. I coat mine with parafin and burn it off. Just keep the ladle really cleaned and you should do fine.

I can't add a lot to what the others have said, they did a good job of posting some good advice.

Good Luck,
Ron

[44man]

Have found a full ladle works better filling out the bullets in the mold
Adds:
* With ladle spout fitted tight on the mold in the vertical position pour for 5 seconds. The create a nice sprue puddle of melt. When the sprue puddle consistently at 5 seconds, you are at the correct casting temperature
* Then cut the sprue
* Consistent rhythm is the name of the game for casting good bullets
Plus read this ... http://www.longrangebpcr.com/8Phases.htm

Friends have filled it too full and lead poured from the ladle itself all over my bench!
Pressure pour is a myth, you can not compress liquid lead.
Ladle pouring from height will have the sprue set before the boolit gets enough unless you keep pouring lead all over to keep the sprue molten.

[HangFireW8]

Pressure pour is a myth, you can not compress liquid lead.

I don't understand the myth part. You can have plenty of pressure without compression (compaction, decrease in volume). Hydraulics work this way- the hydraulic oils are selected for lack of volume change under pressure, but under pressure they can move a lot of stuff!

HF

['74 sharps]

A wax-based 'lube' may be just the ticket for an object passing through a bore at 2500 fps, but it is NOT a 'lubricant' in the sense of preventing wear between two permanetly joined metal surfaces.

Actually, although it is intended to keep lead from sticking to a mould, Bullplate is a better 'lubricant' at a pivot point than NRA 50/50 ... or any other concoction containing wax.

CM

Would any hi-temp lube work, or is there somethings to be avoided? So far, GREAT tips from everyone....keep them coming..

[44man]

I don't understand the myth part. You can have plenty of pressure without compression (compaction, decrease in volume). Hydraulics work this way- the hydraulic oils are selected for lack of volume change under pressure, but under pressure they can move a lot of stuff!

HF

More lead weight just pushes air out. It will never make the boolit heavier.
You have a correct handle on on hydraulics and that works because fluids can not be compressed and will move what they push on. That means only air in a mold.
A full ladle or one with just enough to fill with a sprue left will have the exact same boolit.
The same as a bottom pour. You can have a full pot and run it almost empty and the only thing that will change is the flow rate through the spout. THAT is what changes your boolits due to heat loss with different rates.

[HangFireW8]

More lead weight just pushes air out. It will never make the boolit heavier.

I agree with that. More pressure just helps force the air out. That can be a hard job as the air is heating and thus expanding. That is why more pressure can be helpful. Better fillout is what makes the boolit heavier.

[canyon-ghost]

Don't get in a hurry, relax, I suppose that is the most important thing I can tell you!

Right there, 44man said quite a lot. I start by plugging in the little ladle pot then, I gather my tools and molds. I wait until it shows liquid at the surface until I drop a chunk of wax on top. It takes a few minutes for the white smoke to start then, I light it. I let it all burn down until it goes out leaving a blackish crust on top. It burns the dross down to nothing. Then I skim it off with a long handled teaspoon with about 6 little 1/4" holes drilled in it. I stir it a little and drop the ladle in. Preheat your ladle or you get a solid chunk of lead stuck inside, you'll see.

When the ladle is floating by the heating element without any lead clinging to it, it's time to pour. I leave the mold on the edge of the pot but, it's usually the first dozen pours that bring it up to temp. Then, it's time to pour like a madman! I watch carefully when the lead on the sprue turns dull and give it an extra 30 seconds.

One thing I do differently that I don't even recommend, I pour from the ladle with about an inch between the sprue and ladle. I never got used to pressing the ladle to the sprue plate, just felt clumsy. I do most of this with long handles and generally stand. I don't wear gloves either. I rely a lot on my own perception and co-ordination.

I hear a lot of people tell me that they don't have time to ladle into two cavity molds. Aren't they the same ones that stare blankly into a TV for four hours?

Good Luck,
Ron