Casting brass

[Maker]

My dad's 50th is coming up and I've had an awesome Idea for a present, a brass Vulcan bomber. I'm thinking I'll carve a wax one as best I can, make a mould from it, melt out the wax, pour brass in and finish it up with a file and sandpaper. I'm confident I could do it but first I have a few questions.

For the mould, I've heard of people using plaster of Paris for non-ferrous parts. Is this a good Idea for me and are there any better options like normal greensand, I'm mainly looking for a good surface finish and it being easy to work with?

Should I make a 2 part (cope and drag?) mould and take the wax out or make it all one piece and melt the wax out?

Does brass need a flux of any sort? (I'm using brass because I have some scrap bits and it's heavy(= nice))

For a crucible, I'm thinking of welding together some bits of 40 x 8 flat bar because I've got a load of it and I'm guessing 2mm wall box section won't stand up to the task.

Oh, and I've never cast anything before, so some general casting information (or a link) would be great as well.

 

[mike 109444]

You need to watch "timeteam" they have had bronze casting on there done in the open using the lost wax method. If I recall some have used flower pots to melt the metal down (don't forget to plug hole in bottom, of pot!)

 

[doubleboost]

There is loads of casting info on you tube
I as well as many others have vids
Be better to cast bronze it is much cleaner & safer than brass
How much weight are you wanting to melt

 

[DanielW]

 

[doubleboost]

nice foot protection lol

 

[julianf]

For my furnace build (in progress - kind of) im using a burner from a domestic boiler. I have more biodiesel than i need, so it seems the easiest option.

Cheapest insualtor for the furnace is probably perlite / pre-mix fire cement, but i dont think it lasts that long... but then youre not going that hot with brass.

People use old gas cylinders, or beer kegs. Im on the look out for a stainless hot water cylinder, as the diameter will be larger than 47kg propane tanks (i want to do larger alluminium melts, so a larger diameter crucible)

I know nothing about casting, as i figured id look into that later. Ive been concentrating on the furnace first.

 

[Maker]

There is loads of casting info on you tube
I as well as many others have vids
Be better to cast bronze it is much cleaner & safer than brass
How much weight are you wanting to melt

I don't know the exact weight but probably around 3kgish.
I'll have a look at buying some bronze to use, I was just thinking brass because I've got some.

For my furnace build (in progress - kind of) im using a burner from a domestic boiler. I have more biodiesel than i need, so it seems the easiest option.

Cheapest insualtor for the furnace is probably perlite / pre-mix fire cement, but i dont think it lasts that long... but then youre not going that hot with brass.

People use old gas cylinders, or beer kegs. Im on the look out for a stainless hot water cylinder, as the diameter will be larger than 47kg propane tanks (i want to do larger alluminium melts, so a larger diameter crucible)

I know nothing about casting, as i figured id look into that later. Ive been concentrating on the furnace first.

I don't think I'm gonna build a furnace, just use the oxy/propane I'm buying off W.olly. Obviously a furnace would be better but His birthday is 4 weeks today so I can't waste time on other projects. I suppose I could sit the crucible in half a butane tank and line that with insulation but I really can't be building burners etc.

 

[brightspark]

hope u have a fat wallet for the bronze. scrappies will well charge u for it. decent bronze flows and casts easier than brass does though

 

[doubleboost]

hope u have a fat wallet for the bronze. scrappies will well charge u for it. decent bronze flows and casts easier than brass does though

I am paying £7 a kilo for bronze bushes & valves

 

[DanielW]

How do tell the diff between bronze and copper? I have this pencil sharpener in the form of an upright piano,it looks like bronze but I'm not sure?

Don't know if its worth anything mind?

 

[Maker]

I am paying £7 a kilo for bronze bushes & valves

That doesn't sound too bad, where is it from?