Found Dreaming

Very Nice!

Good job. Metal seems to have been a bit gassy. Must have used automotive bits for the melt and forgot to degas prior to pouring? Good pull off the pattern!!

Thanks everyone

Yes Frank it was more gassy then normal. As a rule I don't degas,and most gas marks if any rub out rather easily, I try to pour as low a temp as possible and only use clean remelt ally ingots or runners and sprues, and for the most part I get very little dross, But this time I threw in few pieces of dirty wheels into the pot just to fill it, I'm thinking that's were the gas came from.

I figured it was wheel, engine case, or piston alloy, HAHAHA. That's where the gas was from. I've mentioned this before, not knowing if anyone on the forum has ever tried it or not, but a great degasser for aluminum is a finger tip size piece of those blue toilet bowl sanitary cakes people use to keep your toilet sparkly clean and sanitary. "Tidy Bowl Cakes" are the name brand, which we have here in the U.S. Just a small dollup of one of those cakes stuffed into a perforated steel 3" length of thin wall pipe, spot welded to a length of stainless steel rod and stirred while the furnace is off and you're getting ready to pour, will properly degas your melt and generate an abundance of dross otherwise would be impurities in the cast. Clean off the dross (after the blue cake bubbling stops) and pour your melt. The metal will poor nicer, not chill so fast, nor be as brittle, and will polish up brighter because of some of the alloy being eliminated as dross. You get a better grade of aluminum as a result that won't tarnish or oxidize so easily.

I have look for something similar in the local supermarket Frank, but everything I find is a soft sort of gel, I think the ones that they put it urinals may be more of what your talking about, they are a hard dry substance, shops are closed here to day for Australia Day but will check tomorrow

Nice job Mike!

Thanks Latz

F.C. wrote:I figured it was wheel, engine case, or piston alloy, HAHAHA. That's where the gas was from. I've mentioned this before, not knowing if anyone on the forum has ever tried it or not, but a great degasser for aluminum is a finger tip size piece of those blue toilet bowl sanitary cakes people use to keep your toilet sparkly clean and sanitary. "Tidy Bowl Cakes" are the name brand, which we have here in the U.S. Just a small dollup of one of those cakes stuffed into a perforated steel 3" length of thin wall pipe, spot welded to a length of stainless steel rod and stirred while the furnace is off and you're getting ready to pour, will properly degas your melt and generate an abundance of dross otherwise would be impurities in the cast. Clean off the dross (after the blue cake bubbling stops) and pour your melt. The metal will poor nicer, not chill so fast, nor be as brittle, and will polish up brighter because of some of the alloy being eliminated as dross. You get a better grade of aluminum as a result that won't tarnish or oxidize so easily.

I did a little bit of research on the toilet bowl sanitary type cakes, and apparently the active ingredient is paradichlorobenzene, apparently its also in commercial degasser and its also an active ingredient in moth balls...I brought a 4kg bucket of sanitary blocks today from a cleaning supplies house, they are about 2 1/4 in dia next time I'm casting I'll try them, I'll only use about a thumb nail size tho

http://npic.orst.edu/factsheets/PDBgen.html#products

https://www.google.com/patents/US4861370

the guy that owns the house on the north side of me rents it out, one of his renters left about a 1/4 bucket of shock tabs for a swimming pool when they got booted out.

I've used them in my aluminum melts the bubble like hell, I don't machine too much of my casted aluminum but what I do machines ok.

gotta watch it breaking the damn things up, I've had some chips hit me in the face damn sure don't want some in my eye.

Mike, you need to keep those cakes in an air tight container or they will off gas and decompose. Like I stated before, take a 1/2 to 3/4 dia. 3 or 4 inch pipe perforated with 3/8" holes welded to a length of steel rod to be used as the degasser tool. Break off a thumbnail size piece and stuff it into the perforated pipe (if it's too loose wrap it in aluminum foil). With the furnace off, lid closed, degas your melt. Once the bubbling stops, remove the tool, open the furnace lid and skim... then pour. Also make sure the furnace area is well ventilated. The odor and smoke will smell like burnt fireworks powder but will be intense. If there's no breeze, hold your breath or wear a respirator. I don't know if the fumes are toxic or not. I can't help but believe it ain't good to breath as the intense smell is overpowering to my senses. I've always just opened the shop door (my furnace has always been near the bay door) and kept a fan operating in the shop aimed toward the door. Never had any ill effect from smell'n that odor other than just an autonomic response kick'n in of hold'n my breath. Just be careful with breathing in intense fumes is all I'm say'n.