First attempt at lost wax casting

[Binraker]

My first lost wax casting, a horse head brooch in sterling silver:


One question for those that do this sort of thing everyday:

The casting came out rather black and matt:

After a pickle and polish it came up OK but I was wondering if this is normal.
I used SRS Classic because that's what I got from Walsh, but I am wondering If I should be using Eurovest or Global for silver casting?

[Nick martin]

Wow that looks tremendous!

I've never attempted lost wax casting as I don't have the facilities at present. Did you go down the kiln - vacuum - centrifugal casting route?

Nick

[surfergirl]

That's come out wonderfully! I've not done lost wax casting either so can't help, sorry

What will you turn this into?

[ShinyLauren]

Oh well done! We learned mould making and centrifugal casting at college (loved it!), but I don't have the space or expertise to do my own, so send all my casting out.

Mine generally come back from the caster a sort of matt pale grey colour.

[Binraker]

I carved the original from a block of blue wax with the intention of using deft clay to cast it but it turned out that when I hollowed it out to get the weight down it was now too thin so the metal cooled before filling all the detail so I thought I would have a go at lost wax. Knowing that the first attempt could go wrong, I used some dental silicone putty to make a mould and then slush cast a couple of copies. I ordered couple of casting flasks, sprue bases, sprue wax and plaster from Walsh (which got held up for about 4 weeks due to the weather in America). To vacuum degas the plaster I used a pressure cooker I had previously modified to be a vacuum chamber, a bit of silicone automotive vacuum pipe and a 1.5cfm refrigeration service pump (I have a much better Edwards pump but I seam to have lost one of the seals in a house move so that's out of service at the moment annoyingly). The burn out was done in my pottery kiln with a tinfoil dish under the flasks and the flasks on pin stilts. To do the vacuum while pouring I took a piece of 6mm steel sheet, drilled a hole in it and welded on a hose barb from a hydraulic hose end (The last time I bought hydraulic fittings they sent me the wrong ones so I have a load of swage on ends that I haven't got a crimper for so I just turn off the nut and use them as weld on hose barbs.) then put a piece of 3mm silicone rubber on top of that and attached the pump used for the investing.

[Ebo Von Gaz]

Nice casting. Various logistical difficulties prevent me from getting a kiln at the moment, not least the cost. I'd love to see a photos of your vacuum setup if that was possible (eyes up fridge craftily...) I've got that and a waste oil furnace on the list for a fridge compressor, my heart skips a beat whenever I see a dumped fridge!

[Binraker]

That's come out wonderfully! I've not done lost wax casting either so can't help, sorry

What will you turn this into?

It is a brooch. The back is hollowed out for weight (weighs bout 35g, would be twice that if solid) The nice thing with casting is that can all be done at the wax stage. Then I soldered the pin and catch on (ended up a bit wonky as I had trouble with heating everything to soldering temp without melting anything so i won't show that bit)

[josef1]

I had my flask temp to high and the models were noticeably blacker but yours turned out well so yours cant be to far off ! not sure if a mag stirrer would have enough umph ?
this is the first one I made, still running and gives an ok result,Its enclosed now the video was the taken when I was testing it.
https://www.youtube.com/watch?v=sDCmlWlLYG4