Trouble casting with Stick on Wheel Weights

[Jaak]

I am having a heck of a time casting with the soft lead I recovered from stick on wheel weights. I am using an NOE mold trying to cast a .363 200gr bullet for use in an Enfield no2 revolver. I am using a PID controlled Lee 4-20 pot to cast.

When I first bought the mold I followed the NOE instructions and cleaned the mold with Dawn dish soap and heat cycled it on a hot plate five times. Also lubed it up with 2 stroke engine oil once up to temperature. Once that was done I cast a pot full of bullet using Clip on Wheel Weights because at the time I did not know I needed to use very soft lead. All the bullets were coming out perfect almost immediately. I was pleased. All I've ever used before this mold were Lee molds and they all needed much longer break in.

I have now learned that I need soft lead for the 38/200 cartridge. I can not get the mold to cast perfect bullets like it did with the clip on wheel weight alloy. I keep getting wrinkles. Not the massive wrinkles you get from a cold or oil contaminated mold, but tiny little folds and shallow waves on the surface. These mini wrinkles can be spotted from the tip of the bullet to half way to the base. The bases and lube grooves/driving bands all come out crisp and wrinkle/wave free.

Another problem with these bullets is that they seem to be coming out 'dirty' for a lack of a better word. Most of the wrinkle bullet comes out mirror shiny except for small hazy/milky spots that don't seem to have any consistency, such as always on a certain side of the bullet. I have cleaned this lead using the same methods (wood shavings and paraffin wax) I used for the SOWW alloy that cast without problems.

What I have tried to solve this issue is to disassemble the mold completely and clean it out with Dawn again, and this time I left it in acetone overnight to be completely sure there is no oil contamination. I have slowly added Pewter and cast a dozen times between each addition to the pot until the bullets and sprues are no longer mirror shiny once cooled. Cast fast to make the mold hot. Even measured the temp of the mold to 300c (572f) at one point, but did not go farther as I don't want to completely over heat the mold. It's a nice mold. I took the melt temp all the way to 450c (842f) to try and force the bullets to frost, and even at that temp with an overly hot mold that was start to stick, I was getting the wrinkles and dirtiness I mentioned and no frosting. I didn't want to push the alloy and hotter.

I am at my wits end. What am I doing wrong?

[gpidaho]

Jaak: My fix all when an alloy isn't casting up to expectations, add some tin. Tin should help smooth things out without adding too much hardness. Gp

[gpidaho]

By the way, that bullet looks very usable for the intended purpose. Gp

[megasupermagnum]

First of all, stick on wheel weights are practically pure lead. Pure is tricky to cast with for anything other than basic shapes or round ball, but it can be done. You will not get frosting with pure lead, that happens from antimony.

The divots you see are inclusions from dirty alloy. I assume you are using a bottom pour pot? I get the same things, and I believe it to be a problem of having to run the alloy hot causing oxidation, although any pot with any alloy can get dirt trapped at the bottom. The wrinkles you see are poor fill out, but not necessarily from a cold mold.

One easy fix is to add tin. Something like 30-1 alloy is nice and soft, but casts great. When I cast bullets with pure lead, I have to run the alloy hot, around 800-825 F works for me. I've never measured my mold temp, but yours looks plenty hot. One factor often overlooked is the pour rate. Especially with a dirty pot partially clogging the spout, a slow pour will cause poor fill out. Because of this, I don't even bother casting pure lead with a bottom pour anymore, although it can be done. I find it much easier to use a ladle, as you can pour very fast. Often I'll put the spout right into the sprue hole, and pressure pour to fill as quickly as possible. This makes more of a difference than you would think. Another benefit of the ladle, is you don't get those inclusions in your metal. The dirt in the pot will either float to the top, or get stuck at the bottom. Since you take metal from between, and the amount in the ladle is low enough such that anything floats, what comes out the spout is clean metal.

[Walks]

What gp & mega said.

[Patrick L]

I too would look at that boolit and say "Done!" but then again I'm not super picky. Results matter.

[GregLaROCHE]

Try a faster pour rate like the others mentioned before adding tin.

[Neverhome]

Mega nailed it. First thing I thought was hotter alloy and a little tin.
It’s definitely possible to get “perfect” bullets with pure. I’ve used pure on tiny 25 cal hollow points for air rifles with good success but need HOT alloy. The more heat the more oxidation unfortunately so you have to deal with that. Mega summed up all that well

[Burnt Fingers]

Add some tin, smoke the mold, and clean up your alloy.

People laugh at smoking the mold but I'll bet if all you do is smoke the mold you'll no longer see the wrinkles.

[Dusty Bannister]

I was casting some Lee REAL bullets from nearly pure lead for a care package to send to a fellow. I was having poor fill out although I knew I had the melt at 800 degrees and the mold was warmed and should have been working great. I was casting from the Lee bottom pour pot and still getting ugly castings. I decided to just pressure fill the mold a few cycles and see if that made any difference. Shiny and completely filled bullets resulted. After several cycles, I went back to the previous method of about 3/8" or 1/2" drop and the nasty look returned. The weather was not unusually cool, and I was casting in a shed with a vented cabinet so there was not a wind issue.

Ladle filling as well as pressure filling from a bottom pour pot both keep the alloy stream hot until it is inside the mold cavity. There is no heat loss due to air passing by the alloy stream. Maybe the nearly pure lead is just forming a slight oxide and that affects how the alloy acts in the mold cavity. I would never have expected there to be such a obvious difference between free flowing from a bottom pour pot or pressure filling the mold with a bottom pour pot. You might give it a try and see if that makes a difference in your situation. And after filling the cavity, drop the mold a little and pour the sprue puddle to feed the casting.

[mdi]

My first thought was to add a bit of tin to the pot, and from the pic, perhaps clean the alloy a bit more. The surface of that bullet, to me, looks more like a bit of dregs in the alloy, but I don't have the bullet in my hand to make a decent diagnosis...

[Conditor22]

My thoughts are dirty alloy / dirty pot?.
how well do you flux when smelting? I flux at least 4 times, twice with pine sawdust and twice with wax (I feel they help clean/remove different contaminants)
when is the last time you drained and cleaned your pot?

This is what I use: WEAR A FACE MASK!!!
even the wire brush didn't get everything off the bottom

[waksupi]

Use a piece of dowel or other dry piece of wood to stir and scrape the pot sides when the lead is melted. Flux on top doesn't do much. It needs put completely through the mix to be effective in floating contaminants. There is no way to stir a light flu under the surface, as the specific gravities are too far apart.

[rsrocket1]

Use a piece of dowel or other dry piece of wood to stir and scrape the pot sides when the lead is melted. Flux on top doesn't do much. It needs put completely through the mix to be effective in floating contaminants. There is no way to stir a light flu under the surface, as the specific gravities are too far apart.

I paint stirring stick works well. Get a free one at a home improvement store but test it out for moisture. A lot of sticks nowadays are very poorly made with damp wood. You may need to bake out the moisture first.

[Jaak]

Thanks for all the info and advice everyone. I bought a Lyman ladle online as I live in a small town that does not have a shop that has one is stock. In the mean time I am going to clean out my bottom pour pot and go to town re-melting and cleaning that stick-on lead in my ingot casting dutch oven and using some Borax on it along with more sawdust and paraffin.

I also have been using paint stir sticks as wall scrapers on my casting pot.

[bangerjim]

Tin is your leeetle friend, my friend! I use 2% in everything. It makes the Pb more liquid (lowers the surface tension) and flows more evenly in your molds.


Agree with the above comments.

And I sure would be happy shooting those boolits you picture above...........we are not after picture perfect casting here.........just things that shoot accurately.

If those little divots reeeeeely bother you, PC them! I PC everything I shoot.

banger

[robg]

what bangerjim said.and maybe run the pot hotter.

[mdi]

FWIW; I found the "perfect" pot stirring sticks. At a good hardware store a few years ago I noticed some shims. Rough cut, about 1 1/2' wide and close to 12" long. one end is about 3/8"-5/16" thick and it tapers to a flat point on the other end. The rough cut seems to work better for adding a bit of cleaning while stirring and I paid less than $5 for a bundle of 18. Maybe my imagination, but they work better than the smooth finished paint sticks...

[bangerjim]

Most shims are a different species wood than paint sticks. More resins in the shims. The ones I have are yellow pine and that wood works great for a flux. But any carbon-based life form will work as a flux, some just a LOT better than others. I use soft pine sticks for stirring and scraping my casting pot. Fluxes, scrapes and cleans all at the same time!

banger

[Wayne Smith]

I had to laugh when you stated that any carbon life forms will work as a flux - It wasn't intentional but I found that wasps pop when they fry in the lead.