Casting Scrap Aluminium

[Ruairidh Dunford]

Aged 16, I was building my Ulster and needing a pair of rear mudguard brackets. Fyrth Cross had one casting left, from a batch that he’d made for his own car, he gave me this with the idea I could get it cast in aluminium.

The school had a foundry, but it had not been used for years due to H&S.

I approached Mr Hannaford, my Tech master, about how I might go about getting some cast. I was told to return, after school, and he would help me.

We pressed the bracket into the sand mould and I was told to stand back. Mr H had a huge leather apron on, with leather gauntlets and a full face mask. He smelted some scrap aluminium and then poured - the first one was bubbly, so we tried again. The next two were perfect and are still on my car today.

I met with Mr H a few years back, he told me that it was the last time the foundry was ever used and he was elated to be able to fire it up.

The foundry building is long demolished and the Tech department is now largely computer based. I found the bubbly reject casting at our parents’ home last week…

[Mark Dymond]

You can get some good results with relatively rudimentary equipment so give it a go. It not been said here so Ill add what might be obvious. Best results will be from Aluminum scrap from a cast part, rather than extruded or rolled.

[Duncan Grimmond]

Quote "I found the bubbly reject casting..."
Did you use a de-gasser tablet in the crucible Ruairidh? Casting melted scrap can be a bit of an unknown and when I was at college we used de-gassing tablets held at the bottom of the crucible with a perforated plunger with a long handle.
Ghastly fumes but whisked away with the extract fan... good castings followed.
IIRC they came from a Birmingham based casting supplies firm Foseco

[Ruairidh Dunford]

It was last century, Duncan. Regretfully, I can remember only what I have written above…

[jpsmit]

It was last century, Duncan.  Regretfully, I can remember only what I have written above…

I was waiting for that answer. I can't remember what I had for breakfast. 

In a similar note, in our new home 9we have just moved 2 hours east of Toronto in anticipation of our immanent retirement, there is a school for the deaf. It used to be a residential school and it used to have hundreds of students, now there are less than 100. My brother was the principal of another school on the same property and regails me with tales of the large complete wood shops and machine shops that remain in the basement of the original school - now long out of use. I totally understand H&S and declining student populations etc but, it does seem something has also been lost.

[Nick Lettington]

a few random pictures of the process I followed...

  former, spree and release agent.jpg (Size: 138.25 KB / Downloads: 275)

  biscuit in sand box.jpg (Size: 97.01 KB / Downloads: 276)

  biscuits.jpg (Size: 110.47 KB / Downloads: 277)

  casting box.jpg (Size: 210.12 KB / Downloads: 275)

  set up.jpg (Size: 212.86 KB / Downloads: 275)
   

[Duncan Grimmond]

Excellent stuff, well done!
(Ruairidh, I too was there in the last century, born in the exact mid-point! Now an officially recognised crusty old git!)

[Tony Griffiths]

My good friend the late Stan Whinham had searched for years for a hub cap for one of his vintage Humbers.   Stan decided to cast one out of scrap aluminium.   Having made the mould he banked up the open fire in the lounge, opened the under-floor draught and sat his crucible in the glowing coke.   When the scrap had melted he decided to skim the dross off the top using a piece of bent steel strip.  This resulted in a major pyrotechnical display of sparks and flames upon which Stan's wife Betty, who bore more than a passing resemblance to Thora Hird, came into the lounge and gave him a major rollocking.  Suffice to say that the next day Stan was in B and Q buying paint and the next few days were spent redecorating the bungalow rather than playing in his garage.  He told me that he may have had some scrap magnesium amongst the aluminium he decided to melt.   The irony is that at the next autojumble he attended he found one of the elusive Humber hub caps!
Happy days!

One day, in the early 1970s, I went to work, forgetting to close the under-floor draft feed and close the dampers of the back boiler in the lounge. Fortunately, a friend happened to call in to collect something and, upon opening the door, discovered what he called "A minor Bessemer convertor at work". So high was the temperature reached that the cast-iron grid had melted. Amazing that such a simple fire could do that.

[dickie65]

I have cast lead with a camping paraffin stove and steel saucepan. Fist time the plaster of paris mould still had moisture in it the results were spectacular as the water boiled off spitting out molten lead.
Second attempt was fine after the mould was left in the oven to dry out.
I have yet to try re casting any Austin Alloy of which I have a lot of scrap.

[Jamie]

Thank you for all of the replies. I have only just been able to log back in to my account: I lost my access details. I have yet to try any casting as domestic matters have intervened, but I shall update this when I do to show how it goes.

Jamie.