Need help

[rak1]

http://castboolits.gunloads.com/imagehosting/thum_213944eed190b9313b.jpg (http://castboolits.gunloads.com/vbimghost.php?do=displayimg&imgid=3049)
Tried casting some boolits today. Got wrinkles on the nose part of the boolit. The base filled out good. Cast at temps of 650, 675, 700, 725 and 750. ww metal used. Lee 170 gr mold for 30-30. What am I doing wrong or is it the mold. Any info will be gladley accepted.
Dick

[littlejack]

rak, welcome to the CastBoolits.
Looks like your mould may not be hot enough. If you are using a bottom pour pot, sometimes the lead in the nipple will become too cool. It is out in the open subject to the cooler air. Before you drop the molten alloy in the cavity, let a small amount out before hand. This will allow hotter material to be dropped into the cavities. Also, may try speeding up your rythem some, (cast faster).
Some moulds need to be run hotter. Heat'em up until they start dropping good boolits. Preheat your moulds on a hot plate or the kitchen stove.
Jack

[rak1]

Thank you Littlejack,
I will try speeding up the casting. I am already using a hot plate. I am using the Lee botton pour pot. Will try letting out a little lead before filling the mold. I may also try lattle pouring too.
Dick

[quilbilly]

warming the mold may be part of the problem but you might try adding some tin. Head on over to Wally World and pick up a bag of size 4 tin splitshot fishing sinkers. Add about 2 per every two pounds of WW lead.

[woody1]

It's hard for me to tell from the photo, but it looks to me like the drive bands and bases are not totally filled out also. Prob'ly more heat is in order. Are you using a thermometer or the settings on your furnace? The furnace settings prob'ly don't mean much except where to set it when you find the right temp. Did you clean the mould. I mean really clean it as in with very hot water and dish washing detergent? Did you heat the mould before casting? If not, do it. If you don't have a thermometer, are any of your boolits frosty? If not, keep cranking up the temp a little at a time until you start getting frosty boolits. Try casting there with a clean mould. If all else fails, smoke the cavities and try that. C'mon back, we'll get you there. Regards, Woody


Oops, I see you answered some of my questions while I was typing. I'm a ladle guy myself. If you've a ladle, try it. And crank up the temp. You should be able to get good boolits with wheelweights alone if all else is good.

[rak1]

Thanks Woody1. None of the boolits were frosty. I cleaned the mold but not with hot water and dish washing detergent. Will reclean the mold and turn up the temp.
Dick

[littlejack]

Yes sir, + 1 on the pre cleaning.
I just today receiverd a mould I won on ebay. I washed it with hot water and dish detergent. After a few heat up cast, the boolits were coming out real nice.

[geargnasher]

The picture is worth a thousand posts, thanks for including it!

Those boolits were cast from a mould that was way too cold, like 150-200 degrees too cold. Hotter alloy won't help, and will hurt the alloy if you get it too hot. Keep the alloy at around 100 degrees above the point that it's fully molten (not grainy or slushy any more) and preheat the mould before casting.

With a two cavity Lee mould, dip the front bottom edge about 1/2" deep into the molten alloy with the blocks held tightly closed for about 30 seconds, or until no lead sticks to it when you pull it out. If clumps of lead don't hang on the blocks it's hot enough to cast with. Then, flip the sprue plate open and dip the tip of it into the alloy for about ten seconds. Close up the mould again and start casting immediately. Now, for continued success, maintain an un-interupted casting pace of three to four complete cycles PER MINUTE. You need to keep that mould HOT to get good fillout. You'll get a feel for it. Don't be afraid to cut the sprues while still soft, just an instant before they freeze solid, but wait long enough so they don't smear molten lead on the blocks. You should be able to cut them with a gloved hand, without whacking the sprue plate with a mallet.

As far as alloy goes, most WW alloy is very stable and has a low oxidation rate, yet casts very well at about 675-700 degrees. If you add 1% tin or so, 675 is usually plenty. Keep it below 750 for sure, as that is the point where the oxide barrier effect of tin is totally negated, and you'll find that it's effectiveness as far as aiding fillout is destroyed.

Bottom line: Clean and degrease the mould completely, preheat it, three-four pours per minute, 100 degrees over full-liquidus for the alloy. Life is good.

Gear

[rak1]

Thanks Geargnasher. I will try it.
Dick

[1Shirt]

I heat my molds in the melt. Have for years! Both alum and iron. Never had a problem.
1Shirt!:coffeecom

[woody1]

So how is the casting going? I'd like to change my posting about turning up the heat. Make sure the mould is up to temp before turning up the heat. You can have very hot alloy and still have a cold mould if you're not casting fast enough especially with aluminum. Regards, Woody

[rak1]

Woody1 I have not had the chance to cast anymore boolits because it is to cold in the garage. Can not cast in the house because the saw dust smokes to much and sets off the smoke dectors. However I did mix some tin into the ww. Calculated % is 93.74% Pb, 2.24% Sn, and 4.02% Ag. Thinking about bring the Sn content up to about 3.9 %. This will bring it up to about Lyman #2. I am thinking about how to make a vent hood for use in the basement.
Dick

[mpmarty]

Dick, change only one thing at a time or you'll be chasing your tail all over the place.

[pdawg_shooter]

I heat my molds in the melt. Have for years! Both alum and iron. Never had a problem.
1Shirt!:coffeecom

+1 on using the melt to preheat the mold. Like 1Shirt I have done so for 40+ years and never damaged a mold.

[canyon-ghost]

Dick, change only one thing at a time or you'll be chasing your tail all over the place.


Yep, on an internet website, you can get too much info.

Ron

[Bad Water Bill]

Sometimes spraying brake cleaner etc on the new mould just doesn't remove all of the cutting oil used in the mfg process. That is where giving your nice new mould a welcome to my house bath in dish soap and boiling water for a few moments helps. It forces the tiniest bits of the oil out of their hiding spaces.

[leadman]

If you get your mold hot and still have wrinkles despite having cleaned it, put the corner of the mold in the alloy and when it starts smoking give it about 15 or 20 seconds more. Then fill it with alloy and cut the sprue when it starts to harden. It will take awhile for it to cool down to casting temp again but this burns out the last of the oils in the cavities.