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bazzer485
03-26-2020, 09:40 PM
There are lots of different ways to flux and what to use, but is there a optimum temperature to flux? ie after the lead has melted and before zinc etc has?
Thanks
Barry


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lightman
03-26-2020, 11:20 PM
I flux when it gets good and liquid. If its wheel weights or some other type of scrap with steel in it I will skim it first and then flux. I've never paid any attention to the temperature.

Dusty Bannister
03-26-2020, 11:24 PM
Please read the section referred to in this link. It refers to a high temperature of molten liquid metal. No specific temperature. But perhaps it will help you understand what fluxing really is supposed to do.

http://www.lasc.us/FryxellFluxing.htm

bazzer485
03-26-2020, 11:28 PM
Please read the section referred to in this link. It refers to a high temperature of molten liquid metal. No specific temperature. But perhaps it will help you understand what fluxing really is supposed to do.

http://www.lasc.us/FryxellFluxing.htm

I realize what fluxing does, but my question is what is the best temperature to do it? Is there a best temperature. A simple question.


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JonB_in_Glencoe
03-26-2020, 11:51 PM
COWW smelting: I skim out the zinkers before I flux. I end up fluxing anywhere from 600º to 800º
ZAMAK 3 melts at 725º, so if you want to flux with zinc WW in there, best do it below 725º

More precisely and universal, I think the best temperature to flux is 100º above the liquidus temp.
for instance, pure Lead liquidus temp is 621º, so the best flux temp is 721º.
Or COWW liquidus temp is 505º, so the best temp to flux is 605º

Bazoo
03-27-2020, 12:41 AM
From my experience I think a hotter temperature is better for fluxing. Seems like the oxides reduce back in easier. Also seems like the melt lets to of dirt/debris a little better.

ioon44
03-27-2020, 08:18 AM
I flux at around 725 F, the saw dust and wax will have thermal combustion and not have so much smoke.

Mitch Harrington
03-27-2020, 08:36 AM
I'd have to agree. I've always fluxed at a higher temp with better results.

gwpercle
03-27-2020, 02:10 PM
Trust me on this .... Sort all the Zinc wheel weights out BEFORE you put them in the pot .
Steel ones will not melt and will float but the zinc ones....They are sneaky .

Flux when it's all melted and flows like water ... 725 - 750 degrees F. is good .
Gary

djryan13
03-27-2020, 02:42 PM
I cast below 700 with my master caster. Should I be raising to 725, then fluxing, then drop down temp to cast?