Tip for the day - Fluxing Sb

[Frank]

I added Rotometals Super Hard, but even stirring and mixing at 800 degrees and it stilled looked like this. :violin:

http://www.castboolits.gunloads.com/picture.php?albumid=123&pictureid=5251

So I fluxed with wax.

http://www.castboolits.gunloads.com/picture.php?albumid=123&pictureid=5257

So how did the wax do? You tell me.

http://www.castboolits.gunloads.com/picture.php?albumid=123&pictureid=5254

Now let's try Marvelux .

http://www.castboolits.gunloads.com/picture.php?albumid=123&pictureid=5255

Marvelux wins. [smilie=p:

[runfiverun]

you didn't cover the top with the wax.
you had oxides in that picture and you need carbon monoxide to return it to the alloy.
marvelux will do that by creating an oxygen free barrier under it's glassy surface before it goes glassy it has a wet stage that does the work.
same as the wax if done properly.

[Lead Fred]

Ive never covered the top with wax, only throw a chunk in the pot.

Guess Ive been a cheap skate with me bee's wax

[GLL]

I use SuperHard frequently. It needs more wax so that the flame covers the entire surface then stir ! Repeat the process a couple times. The froth disappears completely! I also mix alloys in a separate large container ...not my casting pot.

Jerry

[Longwood]

I rub a hot, long wooden handled spoon, on a piece of Paraffin, then carefully dip it down to the bottom of the pot and gently stir.
The melt boils pretty violently during the reaction, but I don't seem to get very much spitting or popping.
I usually do it with some ash from wood pellet crumbs on top of the melt to help prevent spitting.

[Frank]

runfiverun:

you didn't cover the top with the wax.
you had oxides in that picture and you need carbon monoxide to return it to the alloy.
marvelux will do that by creating an oxygen free barrier under it's glassy surface before it goes glassy it has a wet stage that does the work.
same as the wax if done properly.
The top was covered with wax. I forgot to mention I had also just added 1/2 cup of mag shot and stirred before I fluxed. The bottom line is Marvelux worked quickly. It is worth every penny. Now I know wax does in fact take more work as you say. To make wax work requires fluxing more than one time.

[Defcon-One]

Saw Dust!

[lead4me]

+1 sawdust works great.

[runfiverun]

it's the carbon from the sawdust that works, it creates a chemical thingy called carborization in the alloy, which helps bond the molecules into the SbSnPb chain we want.

marvelux does have it's uses, i have used it to flux antimonial ore into an alloy.

if used and skimmed from the top of an alloy it is usually fine, it does have a habit of collecting moisture from the air and holding it on metal objects like stir spoons and lead pots.
and it will suck up heavy metals [nickel/tin] from an alloy if left on top and let go into the glass stage.

[Frank]

The first pot I didn't need to flux. But the second I wanted harder for something else so I added alloy. But that problem is solved!

On the sawdust, I don't have a ready supply and won't be using it. I read somewhere sawdust is used only with bottom pour pots.

[Stick_man]

Just about anything carbon based will work as fluxing material. Paraffin, bees wax, saw dust, small wood chips, wood stir sticks (used for stirring paint), shredded paper, even Marvelux and used motor oil have all been successfully for many years. If Marvelux didn't work, it would have been gone from the market a long time ago.

I have heard many great things about one vendor here that sells some "wonder saw dust / wood shavings" or whatever it is. Do a search for Pat Marlin. (shameless plug for Pat Marlin). I haven't ever used any YET, but do plan on making a purchase before too much longer. I have a bunch of other flux material that needs to be used up first.

It seems like some people put saw dust or kitty litter on top of their molten lead with bottom pour pots to keep the oxygen and resulting oxidation away from their lead. If you do this, just make sure to not let your alloy levels get too low. You don't want to get foreign materials into the pour spout.

[FLINTNFIRE]

Good advice , have used all the above and a few others , when rendering ww to ingots , always good to read what others are using and have used

[geargnasher]

Graphited shot is a pain to melt in sometimes too. Sawdust is your friend, particularly resiny sawdust that will burn.

The borate fluxes do work, but encapsulate oxidized antimony and tin permanently. If you reduce the oxides of tin and antimony with sawdust, you don't lose any of the metals.

Gear