Will chlorine powder work as a degasser for aluminum?

Chlorine Powder?

Harry C.

Let's see...

Aluminum degassers normally remove hydrogen gas from the molten aluminum.

Hydrogen gas + chlorine gas + sunlight = boom

Well I know a heap of folks who use pool chlorine powder or crushed up pool sanitizer tablets..........What makes you think you need a degasser....whats the problem..........are you sure your melt is not too hot or too cold..........I rarely use a degasser of any kind anymore and my castings are fine....... Visit my website:

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snipped-for-privacy@coldmail.com (Roy) wrote in news:41a53414.201343732 @news.east.earthlink.net:

Chlorine is bad stuff. Would be much healthier to build a vacuum degasser for his furnace.

There is a lot worse stuff used in home foundries than chlorine.........which really is not a problem if you stay out of the exhaust fumes during the melt........ Visit my website:

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...Like zinc, at least to the more sensitive people out there.

Yes, chlorine (calcium hypochlorite I believe) will degas it. I'm told a wood stick will also do, as will dry, inert gasses such as nitrogen, CO2 or argon. All have to be held under the surface so the bubbles go through the melt.

Tim (*cough* yum, fuming brass trivets tonight!)

( ^^ sarcastic cough in case you were wondering.)

-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @

If your "chlorine powder" is calcium hypochlorite, it's the same stuff as some of the degassing tablets that are available commercially. Your task, then, would be to devise a way to submerge it, the commercial tablets are used with kind of a cage on a rod to hold them down while they do the business. Just scattering the stuff on the surface isn't going to do much of anything. Usually the commercial stuff is used by the tablet, one tablet for so many pounds of melt, you'd have to figure out how much to use.

Stan

The easiest way to put this stuff at the bottom is by use of a tube.......I used to use a piece of aluminum foil or paper , into which I would put the crushed up tablet or pool chemical, wrap it up nice and tight, insert in tube. The tube was only about 4 or so inches in length and about 1/2" in diameter, and welded to the end of a stainless rod, swirl it around for a minute and remove rod, and contents of tube were gone.

BCS has instructions for making a dry powdered flux insertion tool on their website......... Visit my website:

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I'm not sure what the problem is, I've only had problems with gas bubbles in aluminum scrap I recently picked up. I suspected my steel crucible at first and made a new one. Then I thought I was running my melt too hot, I don't have a pyrometer so I'm letting it run toward the bright red range in a shadow.

This problem melt is 30 pounds of ford pistons a guy gave me, I'm getting huge gas bubbles in anything I pour including aluminum pigs.

I'm going to try the pool tablets this weekend.

I made a degassing plunger by drilling 1/4" holes around the sides of a 1

1/2" black iron pipe cap and welding it to a long piece of 1/2" rod. Drop a small piece of chlorine tablet in the crucible, stand WAY back up wind and push it under with the plunger. Lots of bubbles and a cloud of super poisonus gas for a few seconds but the pour is nice and solid.

The green stick method works great for cleaning bronze and lead and will raise the slag in a pot of aluminum but does not seem to help with degassing..

Yep fluxing is different than degasing............. Visit my website:

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That should take care of it, remember that the Hydrogen and Chlorine combine to HCL or the like and Calcium is dumped on top of Al mix. Skim but be cautious of the HCL gas as it will burn.

Martin