Dreaded Tinsel Fairy

[bedwards]

I've been casting since the late 80s and this is my first visit by the fairy. I've got an old container of Marvelux and probably should throw it out. I use some last week instead of wax to flux and apparently it left a deposit on my ladle that attracted moisture. Tonight I fired everything up and after it got good and hot, started to stir the melt with the ladle. Before I could think, it made a funny noise and blew tinsel everywhere. No burns or damage but am upset that it happened. I built a wooden box that holds a Lee 10lb pot over a Lee 20lb a couple years ago and the sides of the box and the bottom of the Lee 10lb pot caught most of the tinsel. I had glasses and gloves on but got no lead on them.
The purpose of the post is to just remind everyone that it can happen easy and fast even if you've been casting for a long time.

be careful
be

[uncle joe]

I would think it more likely that whatever you used to stir the mix is the cause of the pop. Anything that was left in the pot when you turned it back on would have heated up slowly and the water would have evaporated long before the lead got to the 400+ degrees required to be able to stir it. This has happened to me before so I now leave the spoon on top of the pot while it's heating.

[bedwards]

It's like there was a layer of something left on the ladle. From now on I'm warming the ladle on the pot before I use it to stir.

[Abenaki]

This is why I no longer use Marvelux. I got a small jar of it, to try out.
Almost had the same thing happen!

Thanks for reminding us about safety!

Glad you are o.k.
Abenaki

[WILCO]

Bad things always happen suddenly! Thanks for the heads up. Glad you're okay.

[BruceB]

Marvelux IS HYGROSCOPIC!!

This means that such things as ladles or stirring spoons will gather moisture from the air while they sit around (if they have a coating of the stuff). The next time these instruments are immersed in molten alloy....BLOOOEY!

Apart from this dangerous tendency, I detest the horrible gloppy mess that Marvelux creates in the pot. Suffice it to say that I simply refuse to have the stuff on my bench....it's not worth the mess or the danger.

[Shepherd2]

My only visit from the Tinsel Fairy was caused by a spoon with Marvelux residue on it. I stirred the pot and laid the spoon aside. Later I put the spoon in the melt to stir it and the pot erupted. I never used Marvelux again.

I put the can on the shelf and left it there. Back in those days Marvelux came in a metal can similar to paint can with a press on lid. One day I noticed that it had rusted through the can.

[LUCKYDAWG13]

i have a small jar of that stuff marvelux that my dad bought some 30 years ago
im just going to toss it out and stick with wax and sawdust i just found it and was going to use it

[Bwana]

My "stirring spoon" was one I used a long time ago to scrape the compacted Moly from the corners of the moly vibrator bowl. Since moly attracts water it has a very slight tendency to "hiss" a bit when first used to stir a newly warmed pot. The obvious solution would be to use a different spoon; but, it just wouldn't be the same and it doesn't spit lead. Nice to know about the marvelux as I too have an almost unused jar and I will keep that in mind for future reference.

[cbrick]

I've got an old container of Marvelux and probably should throw it out.

Definitely toss the Marvacrap. Aside from the danger, aside from the horrible mess and aside from the inclusions in your bullets from Marvacrap it will not reduce tin, in fact the opposite is true. It is effective at removing contaminants; this is because the borate anion binds all metal cations and extracts them into the molten borate glass. Unfortunately, this includes any oxidized tin, and so the alloy is depleted of more tin every time you use it.

Marvacrap will also build up on the inside of your pot until it becomes necessary to drain the pot and use a stiff wire wheel on a drill motor and grind the stuff out. When you do this wear a quality breathing filter, the amount of dust is horrible.

I won't even allow the stuff on my property much less in my shop or on my bench. Yes, the stuff is that bad.

Rick

[timkelley]

Put your stirring spoon on your hotplate, to preheat, along with your mold. I do it with my oak stirring stick, the moisture will go away.