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XWrench3
11-02-2009, 08:24 PM
is it just me, or is linotype a lot more temperature sensitive than wheel weights as far as mold fill out and casting speed. i cast three different molds using pure linotype for the first time day before yesterday. it seemed to me, that it took way longer for the sprues to cool properly before i cut them and it turned out right. it also seemed to me that there is a narrow temp range that this will cast properly with, at least to get proper fill out in my lee molds. of course, because it took longer for the sprues to harden, the mold ran hotter, which made the problem worse. i was thinking about that today, and i came up with a spray bottle i will try next time. atomized water on the outside of the mold should cool it down much faster than air colling. i would not want to quench the mold, for fear of warping it. but atomized water should coat the mold pretty evenly. i was running about 70% scrap rate. which is ok, because it gave me experience, and i probably dont need pure linotype bullets all that much anyway. the scrap will just get re-melted, and mixed into alloy with w.w..

stubshaft
11-02-2009, 08:33 PM
I never noticed it. I do however have NO PROBLEM quenching the mold. In fact it is one of the reasons that I water drop boolits. This is not to say that the mould won't warp but I have used well over 16 Lee moulds in this manner and have yet to warp one. When the mould hets too hot (frosted boolits) I just give it a very quick dunk in the water.

Dale53
11-02-2009, 09:27 PM
Linotype casts perfectly at a very low temperature (600 degrees or so) compared with other alloys. It is a true eutectic and "freezes" and melts at one temperature (it is solid and suddenly it is liquid). So, at "typical" casting temperatures it would take nearly "forever" for the sprue to freeze.

Just cast it at a much lower temperature.

It casts beautifully - much better than any other alloy in my experience. That is why this particular alloy was designed by printers in the first place.

Mike Venturino, in one of his articles a year or so ago, mentioned a manicurists fan for cooling his moulds (he learned it from a friend). It sounded good to me. I found mine at TARGET department store (and later learned that Wal-Mart has one also). They only run about $7.00-$8.00 and are 5"-6" in diameter and are found in the FAN department of both stores (NOT in the ladies cosmetic department). I mounted mine on the side of my casting bench where is is less than a foot off the table surface and installed it so it blows DOWN directly on my mould (after I fill it and move it under the fan). It cools my sprues in two-three seconds and also maintains proper casting temperature of the entire mould blocks whether steel or aluminum.

There is a side benefit, also. It cools the stack of bullets I am casting so I can handle them sooner rather than later.

It has been a REAL improvement at my casting station. THANK YOU, Mike!!

Try it, fellows and gals. I guarantee that you will find it VERY useful and is another one of those things that reduce the frustration level by just "easing" the process.

Dale53

XWrench3
11-02-2009, 09:40 PM
thanks for the insight dale. i will try that next time i cast lino. i probably wont run right out and buy a fan however, we have lots of fans around here. and this time of year, they dont get much use.

HORNET
11-03-2009, 05:22 PM
Been using a spray bottle for cooling down overheating molds for a few years. Haven't had any problems from it yet. Spritz the left side, right side, and bottom, wait a few seconds and back to casting. I was worried about the water dunk getting water into the cavities and inviting the tinsel fairy. Don't really have room in my setup for a fan. Also, the spray bottle doesn't spill when I accidentally knock it over.

Uncle R.
11-03-2009, 06:13 PM
I use a folded wet cloth for cooling. Touch the closed blocks to the cloth - left, right, top, bottom - maybe 1/2 second each side. Sizzle sizzle and back to casting. Never had a problem with warpage on iron or aluminum. Tinsel fairy? No way. The water boils instantly in contact with the blocks - if it doesn't you're too cold already and sure don't need to cool 'em more.
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Uncle R.

XWrench3
11-06-2009, 10:15 AM
hornet, i like your idea, and made up a bottle just for this purpose.
i have done the wet towel method. it seems to work fine. but this last time i casted, i was inside my garage instead of outside where i normally cast due to rain. cant cast outdoors in the rain! the inside of my garage is a disaster. 10,000 items in a space meant for 5,000. i had to work for an hour just to set up a SMALL place to cast. i just had a scratch that i needed to itch, and couldnt wait. the only problem with the towel method is it leaves an imprint of the towel on the mold. wich in itself is no big deal,i just dont like it.

fredj338
11-06-2009, 01:48 PM
Yep, you are casting to hot. Lino melts quite a bit lower & I usually run around 650deg w/ it. Just back the heat down a bit.

Jack Stanley
11-06-2009, 10:46 PM
I've been using the fan idea for over twenty years with a bit of a twist . I ingots I use are rather large and have a nice flat surface that when setting the mold on the lead it make a nice heat sink . The fan is positioned to cool both mold and ingot . The heat of casting still warms the ingot in time for me to load it into my secondary pot after I enpty molten lead into the primary casting pot . It works a warmer for the ingot and helps keep the job moving .

Jack

Crash_Corrigan
11-07-2009, 01:28 AM
I just use the Bruce b method of casting and drop the boolits into a 5 gallon bucket of cold water through an old tee shirt with a slit cut through it.

When the level of water in the shallow dish I use dips I add fresh ice cubes. I use an old pie tin to hold my sponge and terrycloth wash rag to cool down the sprue plate and mold to speed up my casting.

XWrench3
11-07-2009, 02:27 PM
jack, what is this primary, secondary pot method you are talking about? is it just for large-long casting sessions, so you dont have to wait for lead to melt?

Jack Stanley
11-07-2009, 11:04 PM
jack, what is this primary, secondary pot method you are talking about? is it just for large-long casting sessions, so you dont have to wait for lead to melt?

The primary pot for me would be a Pro-melt that I do the casting with and try to maintain a good leavel of lead . The secondary would be an old Lee ten pound electric that I welded the hole shut on the bottom . The ingots I use are about nine to nine and a half pounds and the hot molds warm them up .

When the Pro-melt gets to about half way the metal in the Lee is poured into the Pro-melt and the warmed ingot is put into the Lee to melt . A cold ingot is placed on the casting bench to rest the bottom of the mold while the sprue is cooling .

Some molds heat the ingot up and drain the pot quicker than others but the balance seems to keep a steady stream of lead ready to pour at all times .

Hope this helps , Jack