Having a heck of a time with my alloy

[DHDeal]

I'm having issues with a speck of STUFF (tin?) sticking to my mold faces. This has happened to 2 new Accurate aluminum molds. I have casted great bullets with both, but once each I noticed a speck of trash sticking to the mold faces. I know it happens when the molds get sticky opening and try to scrape it off with a Popsicle stick before it gets to be a problem. Naturally, it sticks like super glue and I go ahead and stop then. I can get it off without scratching the mold, but why is this happening?

The particulars are 20/1 alloy at 775° +/- that I flux often. I'll usually drop a small piece of Gulf wax and skim the dross when the alloy gets to temperature and when ever I notice a lot of trash on top of the alloy. I will sift the dross and put it back in and flux again to make sure I'm not throwing out the tin. The alloy is like a mirror after fluxing.

I usually cast large BPCR bullets using iron or brassnmolds and have never run into this before. I've read about this happening to brass molds and how it basically ruins molds, but not with aluminum molds. Also, I don't get perfect bullets unless these aluminum molds are HOT. When I run them hot and fast, I get perfectly formed bullets, until I get the speck of trash.

If it isn't obvious yet, I'm new to aluminum molds. I've cast probably 500 bullets with each Accurate Mold and the bullets are a thing of beauty, so it isn't the mold, it's something I'm doing......

[plainsman456]

Don't worry about it,it happens to all molds.
I had to clean off a new brass mold the other day.

You are not the only one.:drinks:

[Oklahoma Rebel]

did you smoke your molds using a lighter or match to coat the cavities in a thick layer of soot? I have always used alum. molds, and never had this happen, if you haven't, try lee's instructions on "breaking in" a new mold. good luck and keep us updated, oh, also, what are you melting your lead in? TTYL, Travis

[DHDeal]

No, I've never smoked a mold. I never have needed to before. The "trash" I'm referring to is between the bullet cavities, never in the cavity themselves.

The .45 caliber mold I was casting with today throws a large .454" bullet and smoking the cavities may make it a touch smaller (not a bad thing).

I cast with a custom made burner table and a cast iron pot that'll hold about 40 pounds of alloy if I want to put that much in it. A fancy turkey cooker really, just with tables and built to a height where I don't have to bend over.

The alloy is lead flashing with pure tin. I smelted it myself. It's about as close to 20/1 as I can get it. There shouldn't be anything else in it. Heck, I'm tempted to try WW's......

[DHDeal]

No, I've never smoked a mold. I never have needed to before. The "trash" I'm referring to is between the bullet cavities, never in the cavity themselves.<br>
<br>
The .45 caliber mold I was casting with today throws a large .454" bullet and smoking the cavities may make it a touch smaller (not a bad thing).<br>
<br>
I cast with a custom made burner table and a cast iron pot that'll hold about 40 pounds of alloy if I want to put that much in it. A fancy turkey cooker really, just with tables and built to a height where I don't have to bend over.<br><br>The alloy is lead flashing with pure tin. I smelted it myself. It's about as close to 20/1 as I can get it. There shouldn't be anything else in it. Heck, I'm tempted to try WW's......

[runfiverun]

is this spot in the same place?
are you pressure casting?
is that spot on a vent line?

[DHDeal]

Oops, double post for some reason.

Just for fun, I'll try smoking this mold as I can always wipe it off. Will the carbon fill in any vent lines?

One of the cavities has a mind of it's own. One cavity likes a firm contact with the sprue plate and ladle, and the other will only fill out if I give the ladle some room. I may not be explaining this too well.

This particular mold is a 2 cavity with 2 different bullet styles (both 45 caliber). One being a 280 grain WFN, and the other being a 260 grain WFN.

[DHDeal]

is this spot in the same place?
are you pressure casting?
is that spot on a vent line?

On both molds the spot has been right beside a cavity near the sprue plate.

Pressure casting? Such as having a firm contact between the ladle and sprue plate? If that is pressure casting, then yes, that is what I'm doing.

No on the vent line. These Accurate Molds have plenty of vent lines, but the "spot" is always on a flat place. I only notice it when the mold gets sticky opening.

My experience, limited though it may be with pistol molds, is with large BPCR bullets in 40 and 45 caliber (400 and 540 grains respectively). I've cast thousands of large bullets, but these little bullets in aluminum molds is kicking my butt.

[runfiverun]

hmm I'm wondering if the sticky opening isn't caused by a sticky closing.
the mold might be in a bind and not closing quite right.
I have had some molds that just were a pain to operate and a fight from start to finish.

but as soon as I tried another type of handle all my problems went away, and it was like I had a different mold.
I have seen molds close at the bottom and not the top or close with a little twist because of an alignment pin issue.
sometimes the alignment pin thing doesn't show itself until the mold is hot because of the expansion ratio of the mold material.
and sometimes the handles them selves don't show their mis-match until they are hot.

if your doing good until your mold and stuff is up to a certain temp then it starts showing issues I'd look at how the mold is closing or try hitting the pins with some lube at that point and see what happens.

[DHDeal]

hmm I'm wondering if the sticky opening isn't caused by a sticky closing.
the mold might be in a bind and not closing quite right.
I have had some molds that just were a pain to operate and a fight from start to finish.

but as soon as I tried another type of handle all my problems went away, and it was like I had a different mold.
I have seen molds close at the bottom and not the top or close with a little twist because of an alignment pin issue.
sometimes the alignment pin thing doesn't show itself until the mold is hot because of the expansion ratio of the mold material.
and sometimes the handles them selves don't show their mis-match until they are hot.

if your doing good until your mold and stuff is up to a certain temp then it starts showing issues I'd look at how the mold is closing or try hitting the pins with some lube at that point and see what happens.

I think you may have found my problem why my mold is sticky opening. I cast again today and noted that after I cut the sprue, I needed to lightly tap the bolt on the handle and the mold opened easily. While watching what was happening, it seems the Lee handles aren't as tight/good as my Saeco or Cabine Tree handles. I'll either buy a set of RCBS or order a set of KAL handles. The Lee handles have more slop, for lack of a better word, when opening and allow the bottom of the mold to open before the top. Tapping on the bolt allows the mold to open smoothly. I tried the Cabine Tree handle and it opens the mold smoothly but is HEAVY!

I had the pins lubricated well with Bull Shop lube so it wasn't a lack of lubrication there.

I also found that I was running my alloy way too hot. I kept it as near 725° as I could but made sure my mold was at the correct temperature. Well, I also had my sprue plate to tight. Long story short, I was all screwed up. I may still be screwed up, but I had almost no culls and the mold started casting great bullets from the second mold full. No wrinkles or little worm lines today. It's hard to stop when your mold is running great and you have a rhythm going.

I also haven't had anymore issues with specks of "trash" sticking to the face of the mold either when I keep the alloy cooler.

[country gent]

Once you find where and how a new mould wants to run make notes for future refrence. At higher temps the cast iron pot may be releasing some "impurities" that have cooked into the surface same with the ladle. I clean my ladles every so often to keep the crud down they are holding. I recently went to a new rowel ladle and cleaned it good before using with soap water and heat. still got a few bullets with crud spots starting out with it. I use a diffrent pot for smelting / alloying and for casting. I also use diffrent utensils for fluxing than the casting ladle Im using. Makes things run alot easier for me. My pot holds 150lbs of alloy and normally there are 3 of us casting around it. I flux around every 100 bullets or so I cast or when top gets nasty looking. I cast with wood chips and paraffin both. A small hand full of wood chips or sawdust let cook to dry and add a small amount of paraffin then stir working the flux mix thru the lead and the lead up and thru the flux mix. A slotted spoon or long spatula is used here. scrapping the sides good and working the lead.

[DHDeal]

I understand about keeping utensils clean. I just happened to give every tool a wire brush cleaning before this cast. They weren't nasty, just a good clean up for something to do. I also use pine saw dust I keep in a container to Flux with. Every other fluxing, I drop a small chunk of Gulf wax in. If, and when, I notice alloy in my dross, I'll put it back in before my next Flux. I read about tin getting scooped out when you Flux and don't want to waste it.

My pot is smooth sided and can drop the solid alloy out and keep the inside of the pot clean too. I do my best to keep everything clean so I don't have problems from dirt.

The "trash" I was referring to appeared to be lead, it just didn't come off like lead. As soon as my mold came up to temperature yesterday, I kept the areas that had the "trash" on them clean. The stickiness opening didn't lessen from a clean mold face. I would just give the bolt on the handles a light tap and the mold opened easily. I don't "know" that the Lee handles are a problem, but I'm going to get an RCBS or KAL handle to try anyway. After a few heat cycles the wooden handle slides off the metal anyway. I can fix that problem easy enough, but I'll try a new set regardless.

[popper]

You do lube the bolt area on the Lee handles? Also the arms of the handles & screws. I cut the sprue with the plate vertical, close it upside down.

[gwpercle]

You can also tighten up the nut on the Lee mould handles, that will remove a lot of slop . Keeping everything lubed helps too.
Gary

[DHDeal]

You can also tighten up the nut on the Lee mould handles, that will remove a lot of slop . Keeping everything lubed helps too.
Gary

Indeed I do lube the bolt/hinge of the handles and keep the mold hinge pins lubed. When I ordered the molds I needed handles that would fit, so I went the less expensive route and got the Lee's. I've been able to cast quite a few, but I'll still get at least a set of RCBS since KAL Tool hasn't replied to my emails (I understood he was doing guided hunts up in his neck of the woods).

Thanks for all your suggestions and help.

Dale

[Oklahoma Rebel]

GREAT NEWS!!! glad things are working for you. casting isn't that hard, but casting very well requires working out some kinks and figuring out the " Tricks of the Trade". don't be a stranger! Travis

[Shiloh]

All good advice about lubing the moving parts.
As for fill out, I had to take the current mold to about 850 degrees to eliminate rounded corners on the bands.

Shiloh