Guys Need Desperate Help.....

[navnav2006]

Hello
I am casting aluminium A356 in a ceramic mold. Couple of days Back when i poured the metal into the mould due to (lose clamp) the mold separated and metal solidified out side the mold in such a way that i could not pull it across. i want to know in such case what could be done.
The ceramic mold is quite strong and could take heat up to 1000 C.

I am thinking to keep the mold near the furnace.
Any Suggestions from experts Highly appriciated.

[B Satra]

Maybe I'm being too simplistic or don't understand your problem, but 356 melts technically speaking at 1056 F., so I'd suggest putting your mould , unless it's too large for this suggestion, in a steel pan large enough to contain the mould and the melt, and heat it in your furnace, or with a gas torch to melt the offending mess that's causing the problem--e-mail me if this isn't any help and give more detail and I'll try again--rest assured I'm a Yank and we know everything of course !

Regards,

Bruce
vengbsatra@ubtanet.com

[Des Jacobsen]

You could always try a bit of chemistry and put it in caustic soda and dissolve the aluminium.

Need to be careful as Caustic soda is not the nicest stuff to work with.

[niff2966]

Hi,

As your mould can be heated to 1000C i would suggest that you melt the Aluminium (melting point 660C) from the mould.
If the mould can fit in the furnace so much the better, but i suspect that's not the case. Then its the blow torch and a bit of suck and see as they say.

Don't belive "the yanks know everything", are they not the ones that created the world financial crisis?

Greetings from Ireland

[sbi1406]

i HAVE BEEN IN THE FOUNDRY BUSINESS FOR CLOSE TO 4 DECADES, 356 IS STILL USED HERE IN CENTRAL USA FOR IRRIGATION CUPLERS BECAUSE OF ITS LOW MELTING TEMP, MAKES IT VERY EASY TO WELD.
jUST TAKE A OXY-ACETELYNE TORCH AND MELT THE PROBLEM OFF YOUR MOLD! i SUGEST A SMALL ROSE BUD TORCH END, Bill L
w.phxgrp.com

[Geof]

Before heating the aluminum you might want to look at it carefully. If the aluminum expands how likely is it that it will fracture the the mold. You have to remember molds normally get molten metal in them that cools and shrinks, they never get exposed to tensile stresses from the metal expanding.

The caustic soda idea could have a lot of merit.

[diecutter]

I think that if you posted a photo of the problem the feedback could be more specific. All the suggestions given were excellent, but which to use depends on where the metal solidified.

[navnav2006]

Hi all

As some of you suggested I put the mold inside the furnace and fired it till 350 C. So it was easy to pull it appart.

Sorry i could not put the picture of casting stuck inside the mold but could manage to take the picture of casting stuck inside one half of the mold.


The Casting is finally separated from the mold without damaging the mold.

[navnav2006]

Hi all

As some of you suggested I put the mold inside the furnace and fired it till 350 C. So it was easy to pull it appart.

Sorry i could not put the picture of casting stuck inside the mold but could manage to take the picture of casting stuck inside one half of the mold.


The Casting is finally separated from the mold without damaging the mold.