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alces alces
29-12-05, 08:01 PM
i just had a few questions on flux

does it remove forge scale or just stop it devloping

is there any special preporation you need to do on the metal

thanks for the help

Colin KC
29-12-05, 08:05 PM
If you're forge welding, make sure the surfaces are clean & use as much flux (borax) as you like & it will stop/dissolve scale on the mating surfaces (doesn't matter which, which is another way of saying, I'm not sure;))

narsil
29-12-05, 08:07 PM
It both stops oxides from forming and removes them from the surface of the metal, its effect is to lower their melting point and allow them to flow out of the join. However most fluxes won't get rid of thick scale. The best advice is to grind and surfaces that you want to weld to bare metal before attempting to weld. The job of the flux is to deal with the oxides which form as it is heated to welding temperature.

The degree to which you need to prepare the surfaces depends, to a certain degree, on personal preference, some people reccomend degreasing as well.

alces alces
29-12-05, 08:09 PM
thanks for the help :)

now wheres my hammer

Underhay
29-12-05, 08:53 PM
Now that's a much harder question to answer ;)

owen bush
29-12-05, 10:31 PM
one of the reasons that we use flux when joining carbon steels is that the natural melting point of scale is higher than the temp at wich carbon steel is ruined or burns .AT the abs damascus class that I did with jerry fisk we would clean the initial billets surfaces before first weld and then weld draw out cut and fold in one heat (power hammer needed for this one)banging the billet on its side before closing it up .hitting on its side removes the layer of scale on the surface before closing the billet up and rewelding .I would not rely on flux to remove scale just to prevent it its a bit like having a layer of molten glass protecting the steel from oxygen and therefore scale .

owen bush
29-12-05, 10:39 PM
one of the reasons that we use flux when joining carbon steels is that the natural melting point of scale is higher than the temp at wich carbon steel is ruined or burns .AT the abs damascus class that I did with jerry fisk we would clean the initial billets surfaces before first weld and then weld draw out cut and fold in one heat (power hammer needed for this one)banging the billet on its side before closing it up .hitting on its side removes the layer of scale on the surface before closing the billet up and rewelding .I would not rely on flux to remove scale just to prevent it its a bit like having a layer of molten glass protecting the steel from oxygen and therefore scale .

monkey_pork
29-12-05, 11:04 PM
Almost as an aside ... What is the flux used in this kinda work ?

I'm used to small scale stuff as I fiddle about with electronics and err, plumbing ... but I'd guess it's a different material at forge temperatures (not to mention being a little bit thicker and hopefully less smelly :P)

Colin KC
29-12-05, 11:16 PM
Borax mostly MP;)

monkey_pork
29-12-05, 11:18 PM
Borax mostly MP;)
Thanks,

Is it a paste, kinda ... ?

Colin KC
29-12-05, 11:19 PM
Thanks,

Is it a paste, kinda ... ?


Nah, a powder;)

narsil
29-12-05, 11:25 PM
Thanks,

Is it a paste, kinda ... ?

Borax paste is used as a flux in jewellery, but the dry powder is more convenient for forge welding, although I have heard of borax solution being used to clean out cable for cable damascus.

monkey_pork
29-12-05, 11:33 PM
Ah ... very much to learn here methinks, very much indeed ... :baghead

howiesatwork
01-01-06, 11:36 AM
Anhydrous Borax...