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Lefty SRH
03-27-2012, 07:39 AM
What are some simple ways/methods you guys ensure the right casting cadence? And keeping the mold at optimum casting temp.

LAH
03-27-2012, 08:09 AM
A clock with a second hand will help as will a pot that holds a steady temp. Understanding your mold is right at the top.

Myself I control "keeping the mold at the optimum casting temp" by the number of molds I use while casting.

bruce drake
03-27-2012, 08:21 AM
I line up three preheated molds in front of my pot once my pot is to temp. I just do an assembly line approach where I fill each one and let the heat of the lead in the mold keep the 2 other molds to temp as I open the first mold. Once I pop the first mold open I refill it and set it down then take up the second and then the third in that order. By the time I get back to the first mold, it's set and is still easy to pop the sprue plate open. I can do this for about an hour without any major breaks in the casting other than to occasionally drop the sprues back into the pot before my arms tire out and I need a break for water (or other refreshments) or clear my tabletop off of the piles of boolits.

ku4hx
03-27-2012, 11:14 AM
Cadence is the artsy part to me ... it all depends on too many variables to quantify accurately.

geargnasher
03-27-2012, 11:49 AM
It's voodoo, pure voodoo!

First, you have to find a pink Fez with a propeller on top........but that's another story!

a $10, plain-faced wall clock with a second hand from any of the chinamarts will do nicely for learning, once you get the hang of it you can tell just by looking and by feel when your temps are right. It's just like learning to drive a car: At first you have to pay attention to every single part of the process, and it takes all of your faculties. Then your brain begins to learn and react subconciously to the dynamics of piloting a vehicle, pretty soon it's automatic as your foot learns how to keep a steady speed in hills, your eyes learn how fast you're going by the speed of things going by rather than looking at the speedo every two seconds, your hands make smaller and more precise steering corrections, you generally get a "feel" for driving. Same thing with casting boolits.

To start out, some basic guidelines that work for me: Get a casting thermometer, determine the point at which your alloy is just barely fully molten (end of the mush phase), and set your alloy temperature at 100 degrees hotter. For wheel weights plus a little tin this is around 675 degrees. Straight Linotype will be about 575 degrees. If you have any tin in the alloy stay under 750 whatever you do! Once you get your alloy set and stable, it's good. Forget about it. The rest of it is up to the mould temperature, condition, and your technique. Most of my moulds run wheel weight alloy at about three-four pours per minute, although some 500+ grain single cavity steel ones overheat quickly and only do about two a minute max, and some I can fly through six or seven a minute and barely keep it hot, but those instances are rare. Preheat your mould and time the pours for a while, don't stop and fiddle with the castings you just made, because the mould loses significant heat by the second. Don't be afraid to cut the sprues while they are still soft and you can do it by hand with a good glove. Cool alloy and hot mould will get you there, you'll get the hang of it after while.

Gear

fredj338
03-27-2012, 04:32 PM
If casting w/ a pair of 2cav iron molds or 6cav Lee, I cast at a pretty fast pace, about 3-4 pours a min. Then when the mold gets hot & switch to the other mold. THis seems to keep modsl @ working temp w/o pver heating.

Sonnypie
03-27-2012, 06:30 PM
Do the Hoke-Pokie...

I put my left hand forward,
Right one lifts valve handle up,
I do a quick shift back,
And I fill her right on up,
I do the hoke pokie,
While the sprew puddle frosts,
And I give swing to cut it,
And I drop the bullets out,
I click the blocks together,
And I swing the plate around,
Resume the first position,
And I'm ready all again,

I put my left hand forward,
Lift valve handle up,
I do a quick shift back,
And I fill her up again.....

Here, you can see, YouTube. (http://youtu.be/ww_7W9CWLlg) It's just 29 seconds....

Ya know, you have to be careful what you ask for.... :holysheep

MT Chambers
03-27-2012, 06:43 PM
Very hard to compete with Sonnypie...but, i think you have to back up and understand each mold and it's requirements, for me most iron molds can be done 3 at a time(alternating), aluminum usually only 2 at a time, some of my molds must be used alone, esp Hoch molds.

Sonnypie
03-27-2012, 07:03 PM
My wife thought I burned myself when she saw me....
It was embarrassing.

runfiverun
03-28-2012, 02:06 AM
i count the sprue cooling time in my head.
and keep that consistent.
i take a peek at the boolits as they come out of the mold, and adjust to keep a consistent visual.