Can't keep the mold hot enough

[leadmonkey]

I just finished my second attempt at casting boolits, and have yet to create any usable boolits. Yeah, I know. I should expect that, and I do, but I could use a little advice.

I am using a Lee Pro 4-20, controlled by a PID controller, and a Lee 6 cavity 356125 mold. I cleaned and prepped the mold according to the advice in the stickies. I'm cooking stick-on wheel weights in it.

All my boolits are coming out shiny and wrinkled. All of the wisdom in the stickies says that's because the mold is not hot enough, and I think that is correct. I've tried all the suggestions mentioned, setting the mold on top of the pot, dipping the end of the mold in the lead for a minute or so, and casting some boolits in it to heat it up. Simply leaving the mold on top of the pot definitely doesn't get it hot enough. I don't like the idea of dipping the end of the mold in the lead, it gets crud all over it that is difficult to get off, and I'm afraid I'll get it too hot that way anyway. I have to guess that I'm not fast enough to keep the mold hot by just casting boolits. I'm a noob. I have to go slow.

I started at 700 degrees for the lead, and raised it to 740. Didn't appear to help much. That should be okay for the lead temp, shouldn't it?
Hot plate? If so, are there any good indications that will prevent me from overheating the mold?
Any other suggestions?

[357shooter]

The hot plate is the easiet method, saves some time too. Dipping the mold in the pot will work too, you just need it to get hotter. If gets too hot (drops frosted bullets) cool it on on a damp cloth for 5 seconds and retry. Your temps seem to be in a good range.

You can stick a cooking thermoter into a cavity if you want to monitor how hot it's getting. I don't recall the good mold temps off hand, it seems 410 rings a bell. Another approach: NOE sells a probe and digital thermometer that requires drilling the mold. It's pretty easy to do, and an excellent approach when you are learning.

[mdi]

If you're having trouble getting your mold hot enough, don't worry about getting it too hot. I have a Lee 6 hole mold and I set it on my hot plate set on "med" (a puck ingot of range will melt on the hotplate when set halfway between "med." and "high", I know, not accurate measurements, but just showing that it's ok to heat your mold on a hotplate a little cooler than lead melting temp). I think you'd have to try pretty hard to damage an aluminum mold by just heating it (I've played a propane torch flame on a mold occasionally and none warped).

[montana_charlie]

I don't like the idea of dipping the end of the mold in the lead, it gets crud all over it that is difficult to get off, and I'm afraid I'll get it too hot that way anyway.

If the 'crud' sticks to the mould, THAT shows that the mould is not hot enough.

Why don't you ditch the PID until you know what you are doing ... then use it for refining your procedure.
You MIGHT find out that it's giving you wrong numbers.

CM

[Smoke4320]

If you do not have 1 to 2% tin add it..
get a sealed top (not open coil) hotplate from Walmart .. Costs a whole 16-20 dollars depending on the sale and type..
turn it up to med to med hot.. lay mold on it spew plate down..let it set there till your lead pot gets up to temp .. It will probably take 3 to 4 pours and you will have good bullets .. If That does not work you still have oil in the mold or lead is not hot enough in almost all cases

[HeavyMetal]

I think to much attention is paid to the over heating / warping of a mold, aluminum or iron, or brass for that matter!

I have only been casting since 1972 and I have never seen a wrapped mold.

The 6 banger mold do require some effort to get good boolits out of them and is one large reason I suggest new casters start off with the new style 2 cav lee molds.

Now here's what ya do:

Leave your lead pot set where it's at

Buy a good exposed coil hot plate, wal mart has them, and HF did as well.

If you have some welding skills, weld a couple strips of 1/2 x 1/2 sq stock to a steel plate, about 5/16 to 3/8 thick, spaced so the mold will set between them on it's side, sprue handle pointed up and using the mold handles to keep it from falling over or off the plate.

If you can't do this turn the mold upside down so the sprue plate heats first and allows the heat to travel into the mold from there, you may have to get "creative" to work around the sprue plate handle. This is why I built my "heater plate" with the sq strips of steel on it.

Set your hot plate to just under medium, put your mold on it, and then turn on your lead pot. Here in LA during the spring summer months outside both are ready to go in about 1/2 hour.

You mentioned you bolits are shiny and wrinkled, to cold a mold maybe but I think another scrubbing with brake parts cleaner and Dawn hot water is called for just to be sure.

Care needs to be taken if you lube the mold, throw out Lee instructions bullet lube will only make it look ugly!

A very lite application of Bull PLate lube or two stroke oil will go a long way here and is very easy to get in the cavites and cause wrinkles.

I have used good old silver antisieze, sparingly, and it works very well.

Boolits should drop out with no issues, however you need to be sure the boolit base is sharply defined before you open the mold and drop your castings. This is the number one indicator your mold is the right temp as is the alloy.

From there you just need to learn to "read" the castings for each mold, they all cast a little different, so you canmake spot adjustmens for each run of boolits.

[Marlin Junky]

Hot plate? If so, are there any good indications that will prevent me from overheating the mold?

Yes to the hot plate. I don't think it's possible to ruin an aluminum mold (even a Lee) on a hot plate that produces 800 watts or less. A brass mold that hasn't been stress relieved, not too sure about that.

Anyway, set the mold on your Wally-World special hot plate; however, not directly on the coil (use a steel plate between the coil and the mold) and let it cook on medium to high heat while you are melting alloy. It makes for a quicker learning experience if your first castings are over-heated rejects. Then you can allow the mold to cool while you start casting slowly. As your boolits become less frosted and more easily fall from the mold (without excessive beating on the hinge pivot) you need to find a rhythm to maintain the casting quality. You are at the right cadence when your boolits go though a color change that lasts a second or two just after they hit the blanket (don't try water dropping yet). When the boolits become difficult to eject from the mold, you're over heating the mold... either slow down the cadence or turn down the furnace. Start experimenting with the furnace set at 700F... obviously, you'll need a thermometer.

MJ

P.S. I purchased my favorite hot plate at WM which has a solid, non-metallic heating surface.

[Teddy (punchie)]

Hey LM

Some molds are differ. Try a different one if you have one.

As of late I'm testing different molds, I have some are almost the same.

I'm using range lead and having almost no trouble but, the first couple casting rounds are doing what your saying. Also have had some lead holding to mold. Heat them up hot and cleaning when done. Lead will shed off mold if hot enough.

Now couple of ways to heat this mold, I would use stove (hot plate) and an old skillet (sheet of tin, sheet of steel) set mold on or in and let it heat up.. Maybe use a torch for soldering, oil will smoke off, color will change at around 400 showing heat. Now the Aluminum mold you better watch, at the right temperature will melt at 1220.

[Jailer]

Instead of all the trickery on getting it pre heated, get something to cover it while it's pre heating on the hot plate. I cover mine with an old steel coffee can with a small cut out that lets the handles poke through. It acts like an oven and heats the entire mold evenly.

[Walter Laich]

I know that even with a super cleaning of the mold I usually have to go through 4 or 5 heat/cool cycles before all the oil is gone. I've also had luck using a kitchen match to smoke the molds. Usually I can do this on first casting and by the time the smoked areas are getting worn off I don't need them any more.
.
I do know I once had to spray Kroil oil in the mold and this did a great job of cleaning it. Was casting good bullets as soon as it heats up
.
do you have a thermometer other than the PID? Worthwhile to check the temp since it could be a cold mold.

[leadmonkey]

Okay, before I cast anymore, gotta go find a hot plate. I'm off to the charity resale stores first.

It also did occur to me that the SOWW lead might need a little tin, but I need to get this temp thing right first.

[JSnover]

And don't bother inspecting the boolits until you feel like its time for a break. While you're eyeballing the hot ones your mold is getting cold.

[Jailer]

Okay, before I cast anymore, gotta go find a hot plate. I'm off to the charity resale stores first.

It also did occur to me that the SOWW lead might need a little tin, but I need to get this temp thing right first.

You're stick on wheel weights are close to pure lead. You're going to have to run the pot hot to get them to cast well.

[bowenrd]

What Jailer said ^^^

You did not mention what you are casting for. If you are casting for a muzzle loader then stick-on weights are OK, just run it real hot.

If you are casting for modern centerfire handgun you need to alloy your lead to harden it and add tin to help fillout.

[Cherokee]

For my Lee 6 bangers I just set them on an open coil hot plate (source unknown) set to medium and start the pot. Both are ready at the same time. For the 356125 mold I would add some tin and antimony, or mix with COWW's. I like COWW + 2% tin for nearly all handgun use.

[leadmonkey]

I found a 900 watt hotplate at wallyworld. So I started everything up again and preheated the mold on the hot plate.

Finally got some results, sort of, with the lead at 800 degrees and the hot plate WFO. It slightly discolored the steel parts on the mold. The sprues solidify in about three to five seconds. The boolits are no longer wrinkled, and are just beginning to show a frosty appearance. I actually got about 25 out of a hundred or so that look acceptable. That's progress. The mold handles were coming loose, so I had to stop. I kinda expected that. I'll be fixing those as soon as everything cools down.

I don't think going any hotter is going to help much more. Yeah, I'm guessing I need to add some tin to the pot.

BTW, I did mention it's a 356125. 9mm 125 gr.

[pearcetopher]

Ill bet your putting the sprues back in the pot immediately cooling it down

[leadmonkey]

Nope. I figured that out first thing.

[ACrowe25]

Not sure if you've solved your problem yet and it's too hard to navigate and read the entire thread but how is the flow on your pot? I too have a lee and at times the flow slows tremendously. As a result I take a paper clip and jam it up in the spout on a gloved hand using pliers. Careful as if you push up, lead will pour out as your just lifting the seal. Anyways. I push it all the way up and rotate it around a couple times.

Too slow of a flow could also cause this IMO. 4-20 can also adjust the flow by how tight the top most screw is screwed. Maybe loosen it a bit.

[josper]

leadmonkey : SOWW is all most pure lead. You also need to add some tin and at least 50/50 soww/coww. A six cavity mold can be a challenge to get up to temp. start with two cavity's and cast at a fast tempo and work your way up to the six cavs. Being a small boolit is also a factor.I would back off of 800degs for the lead , use the hot plate to get the mold hotter.