Fluxing

[mrc1965]

I know I will get many different answers but that is ok. I have been using parafin wax to flux my lead. Still getting a lot of "stuff in my pot". I am curious about different ways to flux. Is their a proper temperature to flux at? Thanks in advance for answers.
Mike

[mac1911]

I have been getting a lot of ash like **** in my pot. I switched to a larger pot and it seems to be getting dirty? I went from toil ring wax to candles to sawdust, but I just cant seem to get the crud out ? am I not fluxing enough also, do the pots need to be treated ?

[454PB]

You will never eliminate "stuff in your pot", since it is constantly reforming.

You can minimize it by controlling the heat and covering the melt. That's a problem with ladle pouring, because you are constantly stirring the melt, but if you use a bottom draw pot, it helps a lot.

What I do is flux well, then leave the dross on the surface as an oxygen barrier. I mostly use Marvelux because I cast indoors with little to no ventilation. However, I've tried about anything you see mentioned here when I have ventilation. Ivory soap is one of the best fluxes I've tried.

I usually cast at around 700 to 750 degrees depending on the alloy, and that's the temperatures I flux at.

[sagacious]

There's not enough descriptive info in your post to diagnose the nature of the "stuff" in your melt. To get an accurate answer, you need to provide all the background info on your lead source, your experience level, your melting setup, the details of your fluxing process, etc, etc. Otherwise, folks have to just guess at what you're seeing... and that's when you get all kinds of conflicting answers.

Read up on fluxing: http://www.lasc.us/FryxellFluxing.htm

Good luck.

[WHITETAIL]

mrc1965, Welcome to the forum!
Now to get to the root of your problem.
Please let us know more info.
What type of heat are you useing?
What type of pot?
What are you melting, WW, Stick ons, Or anything and everything you have?:brokenima

[mrc1965]

Whitetail,
I am using a LEE production pot using wheel weights for casting. I melt everything down and flux it in a cast iron pot over a propane burner. The sludge , or whatever you call it, plugs the spout occasionally. I also have to peel and scrape the sludge off the sides and bottom as the pot empties. I have no problems with the bullets cast, everything fron .224 to .54, just the sludge. It may be normal. Any advice is appreciated.
Thanks,
Mike

[dragonrider]

It sounds to me as though you are casting at too low a temp. turn up the heat.

[mac1911]

since we are on the subject.
5qt cast pot
melting WW sorted .75oz and larger, heeped high. Aprox 40lbs.
bayouclasic high preasure burner
lyman thermometer- thus far most wheel wheights start melting @ 550 600'F I keep it under 700'F, I then flux with saw dust, stir stir stir, then skim off the crud. after filling a few molds the ash begins to appear on the sides and bottom of the pot.
Should I flux again ?

[Bladeforger]

since we are on the subject.
5qt cast pot
melting WW sorted .75oz and larger, heeped high. Aprox 40lbs.
bayouclasic high preasure burner
lyman thermometer- thus far most wheel wheights start melting @ 550 600'F I keep it under 700'F, I then flux with saw dust, stir stir stir, then skim off the crud. after filling a few molds the ash begins to appear on the sides and bottom of the pot.
Should I flux again ?
You might think about casting ingots from the big cast iron pot. Then you can use the ingots in an inexpensive Lee bottom-pour pot. There's no reason to keep 40 pounds of lead molten while you're casting.
Keith

[sagacious]

...The sludge , or whatever you call it, plugs the spout occasionally. I also have to peel and scrape the sludge off the sides and bottom as the pot empties.
Thanks,
Mike

Not Whitetail, but here's an answer for you. The oxide 'sludge' is normal oxidation of the lead and alloy constituents in ww alloy. Scrape the sides of the pot while fluxing-- that helps prevent a clogged spout. Flux as needed, and that will help keep the oxide amounts from accumulating. Some folks will have to flux more often, some less often-- varies with melt temp, humidity, alloy, etc. Good luck.

[sagacious]

... after filling a few molds the ash begins to appear on the sides and bottom of the pot.
Should I flux again ?

Yes, flux again. Fluxing is an important part of melt maintenance. Flux whenever you feel you need to. Good luck.

[lwknight]

A lot of that ash and sludge that keeps re-appearing is simply trapped on the sides of the pot and as its freed by agitation it floats out.
As the level of melt rises thing along the edges get wedged in. Thats why I smelt twice.
I cast large 25 pound piglets for storage then when I need some for casting I recast into 5 or 6 pound ingots.
Usually by the time I start mixing alloy , I have gotten most of the junk out.

[John Boy]

I've used many different flux materials, some with better success that others to have the final objective be just a black ash dross. Have found the melt temperature to flux better between 680-700 degrees.
As for the best fluxing material that produces a black ash dross only ... Borax!

http://en.wikipedia.org/wiki/Borax

I am lucky to have a friend who is an electric utility lineman. Utilities used to use crystallized borax that were 2# cylinders to flux their pots. Times have changed and leading is not done anymore by utilities but I have all the remaining flux from their supply room! [smilie=1:

Many times Sn will be part of the dross but using borax, it amalgamates the Sn right back into the melt. Before casting, I flux the pot and the ladle twice.

[fredj338]

I use sawdust, flux the smelt often. Then when casting, I flux again when adding ingots. I never let the pot get below 1/2 empty. That has pretty much eliminated my Lee pots dripping; clean alloy & never empty the pot.

[WHITETAIL]

fredj338, I agree with you.
I flux with wax, and sawdust.
Then when I am making boolets I
am using a bottom pour pot.
I never let the pot go below a inch from the top.
I have a one pound coffee can and spoon
next to the elect pot.
And as the small amount of sludge comes to the top
I scrape it off and put it in the can.
I do not put anything back in the melt.
All sprues go in the can.
They are saved till next years melt.
And that gets resmelted as a extra clean batch.:cbpour:

[Nose Dive]

Wow... I didn't know about the BORAX trick... I have about 20 LB in my shed for deer skin treatment... Will give this a go tommorrow as i have several pounds of plumbers lead from a sewer line that I salvaged... Usually..just us pine shavings and/or sawdust... am excited to see what the old BORAX will do to my boolits....

below is off Internet..
Flux
A mixture of borax and ammonium chloride is used as a flux when welding iron and steel. It lowers the melting point of the unwanted iron oxide (scale), allowing it to run off. Borax is also used mixed with water as a flux when soldering jewelry metals such as gold or silver. It allows the molten solder to flow evenly over the joint in question. Borax is also a good flux for 'pre-tinning' tungsten with zinc - making the tungsten soft-solderable.[2]

[2_Smithereenz]

Wow... I didn't know about the BORAX trick... I have about 20 LB in my shed for deer skin treatment... Will give this a go tommorrow as i have several pounds of plumbers lead from a sewer line that I salvaged... Usually..just us pine shavings and/or sawdust... am excited to see what the old BORAX will do to my boolits....

below is off Internet..
Flux
A mixture of borax and ammonium chloride is used as a flux when welding iron and steel. It lowers the melting point of the unwanted iron oxide (scale), allowing it to run off. Borax is also used mixed with water as a flux when soldering jewelry metals such as gold or silver. It allows the molten solder to flow evenly over the joint in question. Borax is also a good flux for 'pre-tinning' tungsten with zinc - making the tungsten soft-solderable.[2]

That sounds interesting except the part about Borax is mixed with water as a flux, don't want any Newbies getting the wrong idea on that one! I know that the process they speak of doesn't have anything to do with fluxing lead, but it would be easy for somebody new to get the wrong idea.
I'm totally new to casting, but I've been around enough to NOT make that Mistake of putting anything with Water as an addative into the molten lead. It will splatter and explode just like throwing water into a pot full of hot grease.
Be Careful!

Aside from that, I'm going to try the Borax cause I've got a big box of it that I use for hide tanning and turkey fan mounts. I was also wondering about the soap myself. It's mostly wax anyway, just wondering how that would work?
I've got lots of little bars of soap that I got from Motels while working on job sites out on the road. After a few years of that, I've managed to accumulate quite a little stash of them. This would be a good way to use them up.