casting temp?

[original]

I did my first cast a couple of weeks ago and after a couple of hours they came out looking great. My question is though at first i had the lead around 650-700 and the molds were not all that hot. After a while I turned the lead up to 750ish and dipped the corner of the lee mold into the lead for a bit and nice castings came out. Is the 750 range too hot? I was using lead ingots from a vendor here and all of the lead in the pot was liquid at around the 650 temp. thanks

[JASON4X4]

Lee molds like it hotter

[white eagle]

It depends....your temp may be hot at first then as your mold cycles into action you may have to cool it down

[Ghugly]

I find that the right temp. will cause the lead on the spew plate to harden in 3 to 4 seconds.

[bangerjim]

There are many built-in "common sense" temp indicators to use:

Lead frosts/hardens in about 3-4 seconds on your sprew

Sprew cuts VERY easy..no pounding or hammering!!!!!!

Boolits hiss and sizzle a lot when they hit the drop water

If all the above are watched, you can cast some pretty darned good boolits without the need of a PID controller on your pot or using casting thermometer.

I use a Lee 4-20 pot and always set the dial at 6.5.

Use a hotplate to pre-heat your mold to casting temp levels.....not just warm!

Also use same plate to pre-heat your feed ingots for your casting pot. Saves tons of time.

I have NEVER used a controller or a thermometer and cast perfect boolits......1st drop...every drop.

And do NOT use an IR temp gun.....they do NOT work on shiny surfaces.

bnagerjim

[original]

thanks for the input, just wanted to check if what I was doing was right and not wasting time. I will be using the hotplate thing from now , I was amazed at how fast things cooled down by adding just a little room temp fresh lead to the pot thanks again

[500MAG]

thanks for the input, just wanted to check if what I was doing was right and not wasting time. I will be using the hotplate thing from now , I was amazed at how fast things cooled down by adding just a little room temp fresh lead to the pot thanks again
I use a electrical junction box with the side cut out and the metal lid screwed on and put it on my hot plate. It's sort of a mold oven to place the moulds in. On top of that I place some ingots to preheat to prevent my alloy temp from dropping so low when I add lead.

[bobthenailer]

I usually run my pot between 650* to 700* it depends on each moulds preferences ! and preheat my moulds to about 450* before casting and wait about 7 to 10 seconds for the sprue to harden. if the sprue is not set up by then i use a small electric fan to cool down the sprues until there in the 7 to 10 second range.

With Lee moulds i have found i have to run the pot @ 750* for the mould to fill out correctly and sometimes with a bottom pour pot a little closer to the spout.

[leftiye]

The critical temp is how hot is your mold. Lead of any temp that will pour can be cast - well cast. I use a mold heater whilst casting (actually during the casting process). Good mold temps are in the 325 degree range. A Harbor fart infra red thermometer is nice to have (not too costly). That having been said I cast at 700 to 750 degrees.

[kbstenberg]

Leftiye Just a suggestion. I use a NOE Mold Temperature Monitor. It gives you the imediate temperature. It is really easy to keep the mold within a few deg. All the time.
Theonly drawback is that you have a wire constantly attatched to the mold. But with practice you don't even know its there.