Help w/ Adjustable PP Mold

[PanaDP]

I'm a pretty new caster. I've been casting for 6 months or so. Just a couple days ago I received a KAL adjustable PP mold and I'm having a bit of trouble with it or, rather, with me. I'm sure it's not the mold, which is really a beautiful little piece of machining work.

The problem I was having was a couple type of finning or flash showing up. I had a little fin on the base (between block and base plug) of the bullet a large percentage of the time. I have the set screw keeping the base in place tightened very modestly. I used the end of an allen that gives less mechanical advantage and just used two finger pressure. Could it still be too tight?

The other problem I had was getting little needles of lead that had flowed into the vents. Do I simply have the melt too hot? I didn't really know how to treat this mold so I copied what I do with my BACO money mold, which cast beautifully with these parameters.

I'm casting about 30:1 lead:tin and I kept the melt temp. hovering between 800F and 820F. I ladle pour them and I keep the spout in contact with the sprue plate until lead starts to come out of the sprue hole then I make a sprue puddle.

[Good Cheer]

Just curious, are you using a ladle or a bottom pour spout?

[bigted]

i see that you DID say you ladel pour but sounds a bit hot to me... but ill let others chime in that have more experience then myself.

[powderburnerr]

panadp
you do not need to run the kal mould so hot , between 750 and 800 works about perfect ,
the finning is from a too hot a block as is the base fin , , the mould probably isnt releasing the bullet real easily also
slow down your cadence , do not hold the ladle on the sprue plate quite as long and count to 15 after the puddle on the top hardens , ...
when you get the rythem down the bullets will drop out on their own accord.

[littlejack]

PanaDP:
When you put the spout into the sprue plate when pouring, this is called "pressure pouring"
If the above recommendations do not solve your finning problems, raise the ladle above the sprue plate some so the flow can have some breathing room. This will allow "less" pressure on the melt going into the cavity and not force the melt into places where you do not want it.
Jack

[Yellowhouse]

Running two molds at once helped me out on the overheating. I'm not a patient guy.

[PanaDP]

Thanks, Gents. As per Rick's advice, I'm going to give the base plug a check over under magnification to make sure I'm not pushing it out from the block. I'll also try running it all a bit cooler and see how it does.

[PanaDP]

Now I'm torn. I took everybody's suggestions and cleaned the mould triply well, I broke the edge of the blocks under the sprue plate, and I checked the base plug to make sure the set screw wasn't pushing it away from the block. I also ran the melt cooler, about 775F, and slowed down my casting cadence. I didn't get any of the fins or lead flowing into the vents. Now, however, the base isn't filling out completely to give sharp edges. Should I try and split the difference in melt temperature? I'm not sure what to do.

[montana_charlie]

Now, however, the base isn't filling out completely to give sharp edges. Should I try and split the difference in melt temperature? I'm not sure what to do.

Getting 'perfect' bullets comes from a combination of pot temperture and mould temperature. You adjust one with a rotating knob, and you adjust the other with your casting cadence.
When you changed your cadence AND reduced your pot temp, you made two changes that affect mould temperature.

Now, you don't know which remedy fixed your problem, or which remedy caused your new one ... or if it is a combiation of too much of one and too little of the other.
Welcome to the state of self-induced confusion.

775 degees sounds like a reasonable pot temperature, so stay with it for a while.
Change nothing and try pressure pouring to see if that will fill the base.

If it has no effect, try a faster cadence to bring the mould temperature up.

Change one thing at a time, and evaluate the change before trying something else.

CM

[Seth Hawkins]

I have a KAL mould and do everything you're doing now except I'm "pressure pouring" and I'm getting good bullets. I'm betting that pressure pouring (never heard it called that) will cure your problem.

It took a while to find the right cadence that would keep the block at the right temp, but once you find it you can really produce a lot of quality bullets in a relatively short time. It just takes trial & error.

I Have Found The Single Most Important Thing You Can Do When It Comes To Casting Is Take Good Notes.

Write down everything! It may be some time before you use that mould again. You're not going to remember things like pot temp, cadence, etc.. Having detailed notes will make life much easier in the future. Trust me. I just pulled a mould out to cast some bullets for a friend. I hadn't used that mould in years. Thanks to my notes I was able to get good bullets to drop almost immediately. Without the notes I would have had to re-discover everything about that mould all over again.

[Longwood]

I learned here to sit my molds on a hot plate when I am doing other things.
It keeps the mold at a more even temperature so everything goes better.

[PanaDP]

I'm still having some problems getting perfect bases.

Does it matter where I set the base plug in relation to the vent lines? Should I try to line the base corner up with a vent line or try to avoid that?

[John Boy]

I'm still having some problems getting perfect bases

* Heat pot melt and mold
* Fill the ladle and stuff the spout in the sprue hole
* Hold the spout in the hole for 5 seconds to create a good head pressure pour
* Create a good size sprue puddle and watch it frost ... 5 seconds is a minimum time period. With 500+gr bullets, 8 - 10 seconds for the puddle to frost is optimum If the puddle frosts less than 5 seconds - the mold & melt is too cold. Greater than 10 seconds to frost, the mold & melt is too hot.
* Cut the sprue and with practice, the bullet bases can be used to shave with

And cast with a CONSTANT RHYTHM otherwise your bullet weights will be all over the map

[PanaDP]

I think I'm doing all of those things. The bullets are really good except for that base edge. I cast good bullets with my other large PP mold. This one seems to always trap some air down in the mold at the base edge or something. I can't figure it out. I'm degreasing the mold again right now to see if I left some oil trapped somewhere.

[montana_charlie]

I've never used an adjustable mould, so anything I say is a guess, but ...

You asked about lining the base plug up with a vent line.
I don't see how that would be especially helpful, but at worst it might make a pair of whiskers on the base.
But, as metal pours in, I see no reason to think that air can get 'trapped' in the bottom of the mould.

There IS a lot of extra metal in that moveable plug, so maybe you just aren't getting that part hot enough ... and the alloy is solidifying before it finishes filling the corners.

If that is the issue, I'd say more heat or more tin.

ON THE OTHER HAND ... it is possible to get a mould so hot that corners come out rounded. I don't remember the metalurgical reason, but it's true. So, if you are running in the near maximum heat ranges (850 and more), you might try backing off.

CM

[Don McDowell]

Lining the base up with one of the "vent" slots does help.
But unless and until you heat that base plug with a propane torch or similar , you will keep getting screwed up bases.

[PanaDP]

Lining the base up with one of the "vent" slots does help.
But unless and until you heat that base plug with a propane torch or similar , you will keep getting screwed up bases.

Do I need to do that for every bullet and keep it hotter than the rest of the mold? While I fill the dipper, I've been holding the protruding end of the base screw in the melt to heat up.

[Don McDowell]

No just to get started. That base plug doesn't heat up as fast as the rest of the blocks do, and it doesn't hold the heat as well, but usually once you get it hot the bases should fill out nicely.

[powderburnerr]

I run mine at 750 , I set it on a hot plate set on medium when I plug in the wagge . when the wagge cycles off and the lead is melted I start casting , the sprue has to stay liquid for a 7-8 count and then the bullets will be right ,, if the base isnt filled it is either cold or dirty with contaminates, at this point.I set the mould on the plate with the handles pointing up.

[John Boy]

I think I'm doing all of those things.

OK, how many seconds does it take for the sprue puddle to frost?
And believe instead of us chasing the tail on the dog - post a picture to show what the base of the bullet looks like

Here the adjustable PP mold I use and I do every thing I explained to you and the cupped bases are perfect!



And I don't have to line the base up with any of the vent lines which will create a bullet with a different weight after you determine the weight of the bullet you want

My belief is the mold is not the issue, it's how you are casting. Some molds are stubborn but they will cast perfect bullets and I cast with 63 different molds