I..uh... melted my boolits in the toaster oven

[302w]

Short story: I was PCing my boolits, and I noticed they started to melt. The bases widened, the boolits got shorter, and you see stretch marks in the powdercoat. What did I do?! My alloy seems kinda soft. Is this possible around 400-450 in a toaster oven?

Long story: I'm a newb, obviously. I've been having issues with my boolits, sometimes wrinkley, never quite filling out the mold, etc. I suppose it was zinc contamination. I was also constantly plugging my bottom pour furnace. It doesn't help that I bypassed my thermostat.

I got frustruated and poured half of a quart container full of commercially cast .430"(iirc) SWCs. I don't shoot anything like that and I inherited it. Waited forever for the lube to burn off, and casted the best boolits of my life. Then melted them in my toaster oven.

Overall: I feel like the commercially cast boolits were a soft alloy and near pure lead, and the rest of my boolits are contaminated. I should just trade it in at the scrapyard.. If my "bad" alloy passes the acid test, I will try mixing it with my "soft" alloy.

[jcren]

Actually, commercial cast is usually much harder than needed. What lead source are you using? It can be butched up with other alloys, but check your oven temp first. Even a rich tin/lead alloy shouldn't melt below 500 or so, and powders don't need more than 375-400 for 15-20 minutes.

[bhn22]

How were you measuring the set temp in the oven? Hopefully you weren't relying on the stock controller.

[302w]

How were you measuring the set temp in the oven? Hopefully you weren't relying on the stock controller.

I was.

I still don't believe that a toaster oven could partially melt lead. Is it possible?

[Beagle333]

It can not only partially melt lead, it can reduce it to just a flat puddle in the pan. You need to get a baking thermometer (4-6 bucks at any grocery/WalMart) and see what the thermostat should really be set to.

Refer to this page and slide on down to the left side of the first set of charts. It will show you why your lead slumped.
http://www.lasc.us/CastBulletNotes.htm

[Budzilla 19]

Yes, it's possible. When I did some heat treatment on some .30 cals yesterday, I just stuck the lead thermometer in the top of the door and regulated the temp with that!! Set the temp to 450f (with the thermometer) and watched it closely. Just persevere, and you'll get the hang of it! Lots of good people here to help you out that's for sure! WAYmore experienced at this than me! I kindly defer to their superior knowledge of this subject!! As always, good shooting to you.

[rancher1913]

what they said. my brand new oven for pc'ing was off by more than 50 degrees.

[runfiverun]

450? hmm 450? oh yeah tin/linotype both melt at that temp, add another 50-75-f and you get puddles.

[dilly]

Couple of relevant points.

Alloys that are closer to pure have a higher melting point. If you had linotype bullets in the same tray as pure, the linotype would melt first.

Secondly: The heat in an oven is VERY patchy. I've had some bullets melt and others not melt. A convection oven can mitigate this quite a bit.

Thirdly: The labels on those dials are meaningless. It would be more accurate to say put a high on one end and a low on the other. It needs to be calibrated, and even then it's not really that accurate if you have patchy heat patterns.


The equipment aspect of ovens is comparable to alloys. Lots of good bullets have been made from untested range scrap. Lots of good coatings have been cured with thrift store ovens. To get perfectly consistent, repeatable exact results, expensive foundry certified alloy is required. To get a perfect cure temp, a brand new connection oven hooked up to a PID is required.

Make do with what you have until you decide it's worth it to find something better.

[runfiverun]

and until then do your first run with junk boolits so you can find that slump point and back it down from there.

[NavyVet1959]

I was.

I still don't believe that a toaster oven could partially melt lead. Is it possible?

Uhhh... Obviously the answer to that is "YES"... :)

1. You have a toaster oven
2. You put bullets in it.
3. The bullets are made of lead.
4. The bullets melted.

Thus, a toaster oven can melt lead.

QED

:)

Get yourself an oven thermometer and sit it in there for awhile and see what it indicates. A convection oven will give a more even temperature though. If it is not convection, you will probably have some hot spots and they might be enough to melt the lead even when other spots are not.

Melting point:
Lead -- 621.5 °F
Linotype -- 462-477 °F
Tin -- 449.543 °F

http://www.matweb.com/Search/MaterialGroupSearch.aspx?GroupID=177

[Fishman]

Wrinkly bullets and plugged up bottom pour point to low alloy Temps in your pot. It may be zinc but likely just cold alloy and moulds. Heat your mould on a hot plate set to medium, sprue plate down, while your alloy temp stabilizes at around 720 F. Wait, I guess you stated you bypassed your thermostat. Don't do that unless you have some way to regulate the temp, like a pid. Once you have the alloy to temp and the mould preheated, you will do fine. It sounds like you need at a minimum to do the following: fix your pot thermostat, get a hot plate, and buy a thermometer to measure pot and oven temp.

I don't think your alloy is the problem, simply cold equipment and poor technique. You can fix that! :)

[Handloader109]

And you can be at 350f with powder coating and be good to go. Way better to be on low side than puddles. But get a thermometer..... And you are probably casting too low also.

[ioon44]

"You need to get a baking thermometer (4-6 bucks at any grocery/Wall Mart) and see what the thermostat should really be set to."

This a good place to start as I did, but I ended up with 4 different baking thermometer's and all showed a different reading at the same time with a spread of 30deg F. My HI-TEK boolits kept coming out darker which is not a problem for shooting.

I bought a Digital thermometer with a K-type probe and found that my convection oven was running up to around 445deg F.
So I guess you get what you pay for.

[dilly]

Worse than slumping that obviously ruins all of the bullets is a sporadic minor slump that you can't really see by naked eye very well but makes your cases bulgy on the 3/100 bullets that it ruins.

Guess what I've been dealing with?

[bangerjim]

Get an oven thermometer and forget using the settings on the oven dial!!!!!!!!!!!!!

So many people that use those cheeeeeeeep standard ovens have this problem.

And yes........you CAN and WILL melt/sag boolits in your oven if it gets hot enough. I did it with 2 different "$5" Goodwill ovens B4 I threw them in the garbage and bought a ~$100 convection oven.

banger

[RogerDat]

The cheap stuff is good for getting started, seeing if it works before sinking a more significant amount of money into something. Eventually if you do it enough it makes sense to move to better equipment. Me I'm a big fan of do it enough to prove it is something worth pursuing and learn enough to know what matters in terms of features, layout and what makes "good" equipment "great". Then buy the good tools. Or just throw mad amounts of money at premium equipment that you don't yet know how to use so it can gather dust until a garage or estate sale disposes of it.

Bullets with a "smile" wrinkle are what I see when I don't let the mold get hot enough on the hot plate before I start casting or alloy is too cool. Or if I slow down too much or stop to deal with other things and the mold is not up to good working temp. Good working temps do vary depending on alloy. 2/3/95 of WW with 2% tin needs different temps for melt and mold than 5/5/90 of Lyman #2.

Clogged spout also sounds like not hot enough. It can take awhile for melted lead to get up to full operating temp. Just because it melted does not mean it is hot enough. Lead thermometer is useful. This one is $22 vs. $35 for a Lyman, pretty decent & made in America. http://www.amazon.com/Tel-Tru-LT225R-Replacement-Thermometer-degrees/dp/B0055777EU

I can "see" a molten pot of lead by 600* but casting with this alloy and this mold I'm using below 650* is going to come out badly. Different alloy and mold getting closer to 700* works better. And bottom pour has cooling aspects that I don't see with a dipper. Bottom line if you can't measure it then it is very hard to adjust by a certain amount and examine difference in outcomes.

There are also 500 degree thermometers that are for ovens or hot oil (turkey or fish fryers) that while too low for lead are fine for toaster oven.

If you don't have a hot plate to heat the mold on then you can dip a corner in the molten lead to pre-heat, then pour and cast as fast as you can get the sprue to harden dropping the first few "too cold" boolits aside. Fast casting heats the mold provided the lead is hot enough. Or letting hot lead run off the side which I sometimes do with a ladle when I'm casting. That over pouring of the sprue can help bring the mold temp up in a couple of casts.

[bhn22]

And you can use a PID to control an oven as simply as you could a melting pot. Assuming you already have one of course.

[302w]

The one thing I noticed was that my melted commercial bullet lead was significantly less viscous than my wheelweight lead at the same temperature. That would explain the mold fill out.

Do heating elements lose their effectiveness over time? My furnace is probably close to 50 years old, and I couldn't melt lead with the replacement thermostat.

[rsrocket1]

My $1.68/lb Goodwill Outlet Black and Decker oven holds its temperature quite well for powder coating thank you.

That is, unless you accidentally bump the temperature setting to BROIL. Then you get slumping boolits!

Even with a 400F setting, if your oven does not have a shield to prevent direct line of sight from the upper heating element(s), you may be exposing the boolits to a much more heat than you want. Better toasted ovens have a "heat shield" that prevents direct exposure to the upper heating elements. You might be able to cobble up a heat shield with some sheet metal, foil or something.

[Fishman]

The one thing I noticed was that my melted commercial bullet lead was significantly less viscous than my wheelweight lead at the same temperature. That would explain the mold fill out.

Do heating elements lose their effectiveness over time? My furnace is probably close to 50 years old, and I couldn't melt lead with the replacement thermostat.

I would tend to suspect that the replacement thermostat is bad or incorrect. Did you get it from the pot manufacturer? As stated by many, a good thermometer will discover the truth.

[CGT80]

OP, your alloy must be bad. Just box it up in a flat rate box and ship it to me [smilie=1:



My convection oven is a $40 oster convection unit from walmart. I checked it with the thermometer that I use for my lead pot (although I have a PID on the pot also), and it was very close to what the dial said. I bake Smoke's PC for 15 minutes at 400f, whether the oven is cool or warm from the last batch.

Have you warmed up your ingots on a hot plate before dumping them in the lead pot yet? I warmed up my mold on the hot plate and then laid ingots on it while I cast some boolits. After a bit, that 1100 watt hot plate gave me a puddle of lead.

I didn't read all of the posts, but you will find the answers on this forum, just as I did. Some days go great with casting, and others leave me scratching my head. It is a learning experience.

[leadman]

Walmart sells a DVOM (multimeter) in their auto section for $20 that has a thermocouple you can slide in the door of your oven and read the temperature on the digital scale. Much better than a oven thermometer.

You may find the temperature has wide swings and may not be able to control it very well. So place a couple boolits in it and watch the gauge and the boolits. If you see the boolits slumping replace them and turn the thermostat down and repeat the process until the boolits no longer slump.
When you get tired of that process buy of make a PID. You can use this for your pot and your oven.

[MBTcustom]

Gosh this thread tickled me. LOL!
Don't sweat it 302w (doe! Pun in tended! LOL!) Yep, been there done that. I was heat treating some bullets and I guess I accidentally bumped the dial or something. Yep. Puddles.