[john1]

Hi,

Can anyone tell me the proper name for poop metal ?
Ive always called it poop metal, its used for casting (some) carburetors and similar
intricate castings.
Can't find it in Google anywhere.

John

[Soundy]

Originally Posted by john1

Hi,

Can anyone tell me the proper name for poop metal ?

Umm, Limp Bizkit?

Ive always called it poop metal, its used for casting (some) carburetors and similar
intricate castings.
Can't find it in Google anywhere.

John

Not sure of the exact term you're looking for, but you might find it here: http://en.wikipedia.org/wiki/Casting

[Wino]

Sounds like 'pot metal'................a poor quality metal used in many castings.

[john1]

Hi Wino,

Yes, i think you're right.
I looked it up, and several other pages about pot metal, white metal,
and other similar.

The name i was trying to remember, seemed to me to be a person's name,
the only thing that fitted was 'Babbit's metal' which is described as
being very much like pot metal and used for bearings.
Maybe i was confusing it with that.

The other descriptions of pot metal fit exactly, cheap, low melting
point, used for toys, usually has bubbles and small voids inside,
outside finish usually pretty good, works well with intricate castings,
not very strong, mixture of aluminium, zinc, and broken up previous
castings of similar metal, traces of other metals thrown in to aid
flowing, or finish appearance, or minimise internal bubbles.
Generally of a vague and uncertain constituancy.

Also used a lot in the automotive industry, small cast parts etc.

Yes, i'm pretty certain you have hit the name correctly.

Thanks, John

[Wino]

Pewter is another cheap grade casting metal.

[kiwiguy]

The correct term is "zinc alloy", otherwise known here as sh!t metal

[WebSerf]

Originally Posted by john1

Hi Wino,

Yes, i think you're right.
I looked it up, and several other pages about pot metal, white metal,
and other similar.

The name i was trying to remember, seemed to me to be a person's name,
the only thing that fitted was 'Babbit's metal' which is described as
being very much like pot metal and used for bearings.
Maybe i was confusing it with that.

The other descriptions of pot metal fit exactly, cheap, low melting
point, used for toys, usually has bubbles and small voids inside,
outside finish usually pretty good, works well with intricate castings,
not very strong, mixture of aluminium, zinc, and broken up previous
castings of similar metal, traces of other metals thrown in to aid
flowing, or finish appearance, or minimise internal bubbles.
Generally of a vague and uncertain constituancy.

Also used a lot in the automotive industry, small cast parts etc.

Yes, i'm pretty certain you have hit the name correctly.

Thanks, John

I think the metal with a person's name you refer to is "Woods metal" and is a very low melting point alloy used in fusible links in sprinkler heads in fire protection systems. Babbitt is a mostly lead alloy used as bearing material and pot metal is cast aluminum. There are a lot of other similar alloys for all kinds of things from typeface to bullets.

[john1]

Hi Websurf,

Thank you for your input, I think "Woods Metal" probably was the name
i was groping for.
But its not the name of the material that is used for cheap crappy
castings, often used in the motor trade, and (was) used for childrens
toys. I dunno if they still make toys from that stuff as it contains
metals that may not be allowed these days in childrens toys.

Wood's metal is more of a specialist sort of alloy, with exceptionally
low melting point, used where its low melting point is a necessary
feature.
As you mention, such as the sprinkler head seal.
Also it is used where joints need to be made with soft metals which
can only be made using another metal.

If thats the name i was thinking of, then i was mistaken cos that is
not "Crap Metal", in fact it might be quite expensive, and not a wide
spread casting material.

I still feel pretty sure that the metal i am referring to is "Pot
metal" which does have aluminium in it, but its not only aluminium.

And i have recalled another feature which may help to identify it,
which is that when this metal breaks, the broken surfaces are often
crystaline in appearance, and have little sparkly bits.
Dunno if that rings a bell with anyone.

Regards John

[philtivvy]

Hi john1
I think the name of this zinc alloy is Mazak (not sure of the spelling), and it is a ***** to solder or weld too much heat and it just disappears.
Regards
phil

[john1]

Hi Phil,

Yes it is a very awkward metal to work with.
One of the problems is that it contains many voids and bubbles, this
in normal use is not normally a problem, just makes it a little
lighter.

As its cooling and solidifying, the surfaces normally solidify first,
leaving bubbles and voids within the more bulkier bits ... usually.
Any that unfortunately have a bubble or a pit in any surface that
matters to its function, would simply be put back in the pot, to be
part of the next bunch of castings.

This means that anyone trying to repair a break in such a casting is
in a very awkward position.
Too hot and it will shrink away, as the voids become lost, giving the
impression of the metal disappearing.
They do make special low temperature fluxes and solders for this type
of job, but they do need practice and experience to get satisfactory
results.

They also make quite strong glues these days, which can often make a
repair which is very near permanent.
Also drilling and tapping is a very effective repair but clearly can
only be used where its possible to put bolts into the casting.

All in all, repairs to this type of material can be very difficult,
and at times only worth the trouble if the part is virtually
unobtainable.

Regards, John