Idiot Question

[chaos]

I have a new question about the joys of Aluminum moulds. Instead of using a wet rag to cool the sprue plate, would a Heat sink removed from a VFD or such not work well. Anyone tried it?

Colby

[Dusty Bannister]

http://castboolits.gunloads.com/archive/index.php/t-107964.html

Search feature is very handy. This is from the archives so yes, it was tried.

[454PB]

There's no reason to make it complicated.... I usually use the damp rag method, but I have also used a small container of water and just touch the bottom of the filled mould to the water every third cast or so. I know everybody freaks out about having water around molten lead, but I keep it two feet from the pot and allow the water to sizzle off the mould before another cast. Works great, and I've never had a bad experience or warped mould doing it this way.

[Kraschenbirn]

I place a 6"x8" piece of 3/4" aluminum tool plate next to my bottom-pour pot and use that as a heat sink, holding the mold on the plate until the sprue frosts. Never had an overheating problem with any mold, aluminum or iron.

Bill

[OS OK]

I place a 6"x8" piece of 3/4" aluminum tool plate next to my bottom-pour pot and use that as a heat sink, holding the mold on the plate until the sprue frosts. Never had an overheating problem with any mold, aluminum or iron.

Bill

I'm with you on that aluminum plate, the mass of it must make it like a heat sponge. I use the bottom aluminum plate on my Lee Drip-O-matic.

[Bazoo]

I cast in tandum or just slow down and inspect bullets a few minutes if I'm running hot.

Thanks for the tip on the heat sink. I might give that a try.

[bbogue1]

When the mold heats up too much I stop, leave the mold on the rim of my Lee bottom Dripper and take a while to put sprew back in the pot. I spend a little time culling bullets and then back to casting. I figure the melted lead will cool a bit when I put sprew and errant boolits in, however it heats up quick, I usually run my pot at least half full.

[Bazoo]

I use a lee magnum melter. When letting alloy run over the sprue and back into the pot, I've found I get splashes if I get less than half full. Pouring that way I get the best fillout using wheel weight alloy with minimum tin added. I run the mould hotter that way.

[gunarea]

Hey chaos
Myself and several of my buddies shoot Lawnsteel exclusively with cast. We have been using a long fin computer power supply heat sink with an integral fan for several years now. Powered by a cel phone charger that supplies 6v modified ac current. Photos and detailed documentary are on the Cast Bullet Assoc site under the thread title "cooling the mould". So many other methods are used by casters that "kinda" work, but most do not produce zero variation results. Some of the procedures are actually detrimental to producing superior quality projectiles. Need/want more info? Just ask.
Roy

[robg]

If your mold gets to hot try using more molds in rotation ,two or three work for me .gives time for molds to cool without having to slow down.I cast 357/45-70/308 at the same time can usually cast a few hundred in an hour.

[rintinglen]

I place a 6"x8" piece of 3/4" aluminum tool plate next to my bottom-pour pot and use that as a heat sink, holding the mold on the plate until the sprue frosts. Never had an overheating problem with any mold, aluminum or iron.

Bill
+1. I do the same thing these days

[Drew P]

Yep the slab of metal method is way better than we rag. The rag will dry quickly and is more complicated and touchy by far. Just find something metal and flat (I use steel plate) it works brilliantly.

[JM7.7x58]

I was having some smearing, galling, and scoring problems. In looking for some answers I came across BruceB’s posts. His posts on speed casting and sprue plate cooling helped me a lot. I like how he set up and how he worked his molds. His method of cooling sprue plates was dead simple.

I was getting lead smearing on my sprue plates and scoring/galling on the tops of my aluminum molds. I’ve done three things to stop this.

1. I cool the sprue plate per the BruceB method. Wet rag quench.
2. I stoned the bottom of all my sprue plates.
3. I started lubing my molds with two stroke oil.

I want to cast good and fast. I don’t want my mold to cool down. Aluminum molds run better when hot. I do however, want my sprue and sprue plate to cool down fast. A quick three count touch to a wet rag does what I need.

JM

[chaos]

Hey chaos
Myself and several of my buddies shoot Lawnsteel exclusively with cast. We have been using a long fin computer power supply heat sink with an integral fan for several years now. Powered by a cel phone charger that supplies 6v modified ac current. Photos and detailed documentary are on the Cast Bullet Assoc site under the thread title "cooling the mould". So many other methods are used by casters that "kinda" work, but most do not produce zero variation results. Some of the procedures are actually detrimental to producing superior quality projectiles. Need/want more info? Just ask.
Roy

Heck yeah. Right up my alley

[lightman]

I would go with a combination of using 2 molds and setting them on a heat sinc. I use a piece of 1/2 X 6" steel bar about 6ft long for a landing zone when I'm smelting scrap. It eventually gets so hot that you can't touch it but by then my 400# pot is getting empty.

[Texas by God]

I usually use three 2- cavity moulds in tandem running the Lee pot 3/4 max temp resting them on my 6" thick cedar casting bench between casts. I never use a pid or wet rag. Cadence and consistency is key. For me and my stuff. Yours may differ. If just casting one style boolit (rare) I use the aluminum plate on the furnace for heat sink purposes.

Sent from my SAMSUNG-SM-G930A using Tapatalk

[Peregrine]

I know everybody freaks out about having water around molten lead, but I keep it two feet from the pot and allow the water to sizzle

Those people are...unnecessarily cautious. I've cast with an open pot under a deck in the rain many
times, with droplets leaking down through the slats and making a hiss when they hit the surface but nothing more.

The way you run into trouble is when when the slightest bit of moisture gets under the surface of the melt than rapidly expands.

You'll get a pop and a splash of molten alloy if you drop and ingot straight into the pot without cautiously allowing it to warm up first, but an odd splash of water onto the pot certainly won't do it.

[Peregrine]

Hey chaos
Myself and several of my buddies shoot Lawnsteel exclusively with cast. We have been using a long fin computer power supply heat sink with an integral fan for several years now. Powered by a cel phone charger that supplies 6v modified ac current. Photos and detailed documentary are on the Cast Bullet Assoc site under the thread title "cooling the mould". So many other methods are used by casters that "kinda" work, but most do not produce zero variation results. Some of the procedures are actually detrimental to producing superior quality projectiles. Need/want more info? Just ask.
Roy

You claim of "zero variation" results is amusing to me, but perhaps I am underestimating your devotion to consistency.

I then presume you take a mold, use it once, then set it on the cooler for a certain interval before using it again?

What sort of relative standard deviations in mass do you achieve?

Actually, no, I partially take back what I said above, "zero variation" is still an absurdly lofty claim. But I am still quite interested in the way you do things.

[gunarea]

Ok Peregrine
Rather than respond to your cynicism, I will address your interest. The most obvious answer would be for you to research the earlier mentioned thread on CBA.

Proper maintenance of all variables is necessary when "zero variation" is to be achieved. Simple consistent cooling of the mould is the topic at hand. My particular casting setup involves a PID controlled furnace, double insulated reservoir, single cavity mould, consistent alloy properties, dedicated casting area, +54 years of casting experience, extensive recorded data and the finest whiskey on this planet. An infrared analysis shows heat transfer and flow in dissimilar metals fluctuate wildly with voids introduced into the host material. Casting is the introduction of a dissimilar metal into a host material with voids. A mould at a consistent receiving temperature, charged with molten alloy at a consistent temperature, with heat removed at a consistent rate and in a manner to yield uniform heat signature, will yield consistency. Removing heat from the bottom of a mould is the most desirable direction as it has the greater host mass. Water will eventually heat and have different cooling properties. Same is true with most metallic forms of heat sink. Ambient air cooling is very effective when timed properly and time is of little value. Just a nugget for those paying attention, a large coffee can bottom up, makes an efficient heat sink and sheds heat at an appropriate rate. In my casting, temperatures are monitored at; pot spout, reservoir center, mould exterior, mould interior, heat sink receiving surface and area ambient. The dynamics of high/low temperature liquid lead, shows measurable differences, ie; weight/size. Maintaining consistent temperatures at critical points will stabilize standard deviations and minimize average deviations. Commonly available electronic scales will show "zero variation" regularly, a higher accuracy beam balance scale is needed to show actual weight differences. In the hands of a Master tool and die machinist, a Sterret micrometer shows "zero variation" from random selection of test examples. It is now much less common for me to extend the effort required to produce what others refer to commonly as "magic bullets". Not only can I do so, my students do so on a regular basis. Heck, I'll wager you could do so, instructed properly.

Last Tuesday I had the pleasure of some mild impromptu shooting competition. Four of the five present were past Florida sunshine state shooting champions. All shoot their own cast projectiles, handload and won their championships with such. To say they are good shots is a gross understatement. Turkey silhouette targets are commonly taken with head shots at distances greater than 70yds using a Ruger Blackhawk with iron sights only. This is not considered a difficult task from those attending. "Good enough" and "minute of milk jug" ammo is not what they use. When I first met each of them, they had never cast a projectile or loaded any ammunition. Now they thrill at beating the teacher. Little do they realize, the pleasure is mine.

Learn and excel.

Roy

[lightman]

I don't have a scientific background but I would think that "zero variation" would be impossible to achieve. But I'm another that strives for it. I cull bullets that my casting buddies would keep and they even tell me that I'm too picky. Their argument is "its good enough". They shoot at a human size target at 7 yards with a "10" ring bigger than an entire 50 yard Bullseye target! But by paying attention to detail, maintaining proper temps and establishing a cadence the weight differences of my cast bullets rival the weight differences that you see with Berger and Sierra jacketed bullets.

But just for curiosity, gunarea, what do you consider the finest whisky on this planet to be?

[Drew P]

Without a monitoring system of the mold temp, like an IR gun thermometer, you could not even come close to a zero variation output. The mold temp itself can vary a lot and still produce similar bullets, but to get absolute consistency you’d have to monitor that temp, as even a slight pause in casting flow can alter this a lot.

[OS OK]

Ok Peregrine
Rather than respond to your cynicism, I will address your interest. The most obvious answer would be for you to research the earlier mentioned thread on CBA.

Proper maintenance of all variables is necessary when "zero variation" is to be achieved. Simple consistent cooling of the mould is the topic at hand. My particular casting setup involves a PID controlled furnace, double insulated reservoir, single cavity mould, consistent alloy properties, dedicated casting area, +54 years of casting experience, extensive recorded data and the finest whiskey on this planet. An infrared analysis shows heat transfer and flow in dissimilar metals fluctuate wildly with voids introduced into the host material. Casting is the introduction of a dissimilar metal into a host material with voids. A mould at a consistent receiving temperature, charged with molten alloy at a consistent temperature, with heat removed at a consistent rate and in a manner to yield uniform heat signature, will yield consistency. Removing heat from the bottom of a mould is the most desirable direction as it has the greater host mass. Water will eventually heat and have different cooling properties. Same is true with most metallic forms of heat sink. Ambient air cooling is very effective when timed properly and time is of little value. Just a nugget for those paying attention, a large coffee can bottom up, makes an efficient heat sink and sheds heat at an appropriate rate. In my casting, temperatures are monitored at; pot spout, reservoir center, mould exterior, mould interior, heat sink receiving surface and area ambient. The dynamics of high/low temperature liquid lead, shows measurable differences, ie; weight/size. Maintaining consistent temperatures at critical points will stabilize standard deviations and minimize average deviations. Commonly available electronic scales will show "zero variation" regularly, a higher accuracy beam balance scale is needed to show actual weight differences. In the hands of a Master tool and die machinist, a Sterret micrometer shows "zero variation" from random selection of test examples. It is now much less common for me to extend the effort required to produce what others refer to commonly as "magic bullets". Not only can I do so, my students do so on a regular basis. Heck, I'll wager you could do so, instructed properly.

Last Tuesday I had the pleasure of some mild impromptu shooting competition. Four of the five present were past Florida sunshine state shooting champions. All shoot their own cast projectiles, handload and won their championships with such. To say they are good shots is a gross understatement. Turkey silhouette targets are commonly taken with head shots at distances greater than 70yds using a Ruger Blackhawk with iron sights only. This is not considered a difficult task from those attending. "Good enough" and "minute of milk jug" ammo is not what they use. When I first met each of them, they had never cast a projectile or loaded any ammunition. Now they thrill at beating the teacher. Little do they realize, the pleasure is mine.

Learn and excel.

Roy

Outstanding commentary, just outstanding!

This would make a most interesting read...even to the 'good-enough's crowd' if it were accompanied by some pictures of your points that you make...especially the infrared heat transfer's ... I've often wondered how it would look if I could see the stream of heat, liken to a liquid spill, rush out of the bottom of the mould and spread into the heat sink.
That would be a very interesting thing to see in a infrared video clip.

Outstanding commentary
charlie

added> Looking into the Y-Tube for something similar, I found this...the temperature moving through the aluminum block is like watching honey spreading across a slanted surface...

Conduction through aluminium block
https://www.youtube.com/watch?v=j8ADJbD6C7c

[gunarea]

Hey lightman
Good catch on the zero, it is indeed a scientific term. Absolute zero is subjective to the forum of discussion. Absolute zero in water is -375k, not a zero in the value. Hardness and softness values do not express extremes with any zeros. Intelligence has several accepted determinations, seldom a finite value containing a zero. Stupid defies calculation. Typically my finished match castings will vary .01gr or less. Hence the need for precision balance beam scales. Most of those educated by myself will not tolerate a .1gr variation, some are more anal than me. Sierra and Berger solids are actually the brands used to refute the ill founded misconception of factory superiority to the home cast projectile. Only the military employs factory ammunition exclusively for shooting competition. Military match ammunition is produced under very different specifications and remains second class to top competitors. My congratulations go to you for seeking knowledge to achieve a level seldom found by most. Attaining your level of competence did not just occur, it was sought after. Dedication, attention to detail, practice and in my case formal education is just part of effort expended to arrive at the level you are. "Good enough" is a self proclaimed boundary to those who are unwilling or unable to put forth appropriate effort. 600 & 47X does not happen with "good enough" anything. Unlike so many here, casting and handloading are very far from what I enjoy doing. Shooting competitively is enjoyable, winning is tits! I do what I must, to do what I enjoy. My shooting coach told me "you ain't that good, everything else better be perfect". Way to go lightman, generally I post less than twice a month, this is #2 in a day.

Akins Bay Red!! Propriety blend of sugar shine maturized with charred cherry laurel. 88 proof, 100% ethyl alcohol. There is another blatant statement that will probably require defense. There is always some within arms reach. Are you an enthusiast, a connoisseur, a fanatic, a drunk. I am all of those. One taste and you will agree.

Roy

[MT Gianni]

If you wait until your shop is around 20 F a lot of these questions take care of themselves.

[Phlier]

Outstanding commentary, just outstanding!

This would make a most interesting read...even to the 'good-enough's crowd' if it were accompanied by some pictures of your points that you make...especially the infrared heat transfer's ... I've often wondered how it would look if I could see the stream of heat, liken to a liquid spill, rush out of the bottom of the mould and spread into the heat sink.
That would be a very interesting thing to see in a infrared video clip.

Outstanding commentary
charlie

added> Looking into the Y-Tube for something similar, I found this...the temperature moving through the aluminum block is like watching honey spreading across a slanted surface...

Conduction through aluminium block
https://www.youtube.com/watch?v=j8ADJbD6C7c

Great video, OS OK thanks for posting that.

Man, there's some smart guys around this place.

[lightman]

Gunarea, what I failed to say was "good post". I tried to word my post in a manner that did not come across as an attack. If it was interpreted as such, I apologize. Its obvious that you have a scientific background while I do not.

I used Berger and Sierra as examples because my limited test show their weight variations to be less than most of the others. Some custom made benchrest bullets are less. This is using digital scales suitable for a handloader and not a scientist. Your .01 varation is outstanding! The military bullets that I have weighed are a big disappointment. The weights are all over the place!

Whiskey; I'm afraid that I don't qualify as an enthusiast or a connoisseur. I'll enjoy 2 fingers of Knob Creek or Four Roses in a coffee cup occasionally but really great whiskey would be wasted on me. Now, my youngest Son is a trader and collector and belongs to a group of like minded individuals. He would appreciate it and may even be familiar with it.

[GBertolet]

I like to use two Lyman cast iron ingot molds, upside down, to rest my bullet molds to cool on. Maybe not quite as good as aluminum, but it does work.

[Peregrine]

Ok Peregrine
Rather than respond to your cynicism, I will address your interest. The most obvious answer would be for you to research the earlier mentioned thread on CBA.

Proper maintenance of all variables is necessary when "zero variation" is to be achieved. Simple consistent cooling of the mould is the topic at hand. My particular casting setup involves a PID controlled furnace, double insulated reservoir, single cavity mould, consistent alloy properties, dedicated casting area, +54 years of casting experience, extensive recorded data and the finest whiskey on this planet. An infrared analysis shows heat transfer and flow in dissimilar metals fluctuate wildly with voids introduced into the host material. Casting is the introduction of a dissimilar metal into a host material with voids. A mould at a consistent receiving temperature, charged with molten alloy at a consistent temperature, with heat removed at a consistent rate and in a manner to yield uniform heat signature, will yield consistency. Removing heat from the bottom of a mould is the most desirable direction as it has the greater host mass. Water will eventually heat and have different cooling properties. Same is true with most metallic forms of heat sink. Ambient air cooling is very effective when timed properly and time is of little value. Just a nugget for those paying attention, a large coffee can bottom up, makes an efficient heat sink and sheds heat at an appropriate rate. In my casting, temperatures are monitored at; pot spout, reservoir center, mould exterior, mould interior, heat sink receiving surface and area ambient. The dynamics of high/low temperature liquid lead, shows measurable differences, ie; weight/size. Maintaining consistent temperatures at critical points will stabilize standard deviations and minimize average deviations. Commonly available electronic scales will show "zero variation" regularly, a higher accuracy beam balance scale is needed to show actual weight differences. In the hands of a Master tool and die machinist, a Sterret micrometer shows "zero variation" from random selection of test examples. It is now much less common for me to extend the effort required to produce what others refer to commonly as "magic bullets". Not only can I do so, my students do so on a regular basis. Heck, I'll wager you could do so, instructed properly.

Last Tuesday I had the pleasure of some mild impromptu shooting competition. Four of the five present were past Florida sunshine state shooting champions. All shoot their own cast projectiles, handload and won their championships with such. To say they are good shots is a gross understatement. Turkey silhouette targets are commonly taken with head shots at distances greater than 70yds using a Ruger Blackhawk with iron sights only. This is not considered a difficult task from those attending. "Good enough" and "minute of milk jug" ammo is not what they use. When I first met each of them, they had never cast a projectile or loaded any ammunition. Now they thrill at beating the teacher. Little do they realize, the pleasure is mine.

Learn and excel.

Roy




I don't have a scientific background but I would think that "zero variation" would be impossible to achieve. But I'm another that strives for it. I cull bullets that my casting buddies would keep and they even tell me that I'm too picky. Their argument is "its good enough". They shoot at a human size target at 7 yards with a "10" ring bigger than an entire 50 yard Bullseye target! But by paying attention to detail, maintaining proper temps and establishing a cadence the weight differences of my cast bullets rival the weight differences that you see with Berger and Sierra jacketed bullets.

But just for curiosity, gunarea, what do you consider the finest whisky on this planet to be?

My "scientific background" is that I got a degree in chemistry, specialized in analytical chemistry, and got a job doing chemical analysis.
I use analytical balances that display mass to .00001g, that's to ten millionths of a gram. The sample has been heated in an oven to drive off any moisture, and taken directly from the oven into a the desiccator where it's living. The balance are mounted on springs and have draft shields around the sample that are close while the sample is being massed because the slightest vibration caused the reading to fluctuate.

As it is, you can put a sample on the balance, close the draft shield, and watch the mass of the sample climb upwards, tens of micrograms a second, because the sample is hungrily drinking moisture from the air around it. It's a race to take 5 separate portions, mass them, and get everything back in the desiccator as quickly as you can, while of course being exceedingly careful not to spill anything or making a gross error.

The variation introduced by the imperfections of the weighing process aren't any concern to me, they're entirely academic since the analytical grade reagents i'm using to produce my reference samples are only guaranteed to be between 99.5-100.5% pure (https://www.sigmaaldrich.com/catalog/product/mm/104933?lang=en&region=CA), because getting the 99.999 Suprapur (https://www.sigmaaldrich.com/catalog/product/mm/104938?lang=en&region=CA) from Sigma Aldrich means you could be paying $1000 for a pound of something as novel as basically table salt, instead of $100.





Akins Bay Red!! Propriety blend of sugar shine maturized with charred cherry laurel. 88 proof, 100% ethyl alcohol. There is another blatant statement that will probably require defense. There is always some within arms reach. Are you an enthusiast, a connoisseur, a fanatic, a drunk. I am all of those. One taste and you will agree.

Roy

I actually sat and stared at this post for quite a while, trying to decide if your posts are just pendant bait.
I bet if you send me a bottle i'll find plenty of alcohols other than ethyl in it. :D :D :D