meltdish disaster. help required

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MrG

Member
Joined
May 11, 2014
Messages
11
Before I describe my disaster I want to wish everyone a happy new year!

I've tried to find information on this site to sort of help me recover from this current situation but find the information is fragmented in as much as some parts are useful in certain situations but haven't found a whole resolution for my problem. As you will see from pics attached I have ended up with two much borax/sodium carbonate in the meltdish. I have only introduced sodium carbonate to try and make the borax more liquid went heated to enable the gold beads to bond together.

I use a MAP propane torch for my melts and have several successful melts but for some reason I seem to have got into a chasing my tail situation on this one. Advice needed as to what would be the best course of action.

An afterthought I have had is that perhaps I'm losing too much heat out of the dish and have noticed in some videos that some people sit their meltdish on insulating medium, I live in the UK an it is currently cold so not sure if I'm getting enough heat to get the job done properly. Not sure whether to write off this meltdish and put the contents into an acid to liberate the pm's or whether I'm not realising some other vital information.

Please see picture and thanks for looking.

Simon
 

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What where you melting.
There are some small beads visible but most seems to be slag.
as flux is meant to do with impurity's,may be most of your material has been consumed by the flux.
If you think there is value there.
Try to soak it up with some silver and digest again once you have consolidated a workable button..
 
Hi Justinhcase

Thanks for the quick response!

I was smelting a small volume of unrefined gold bonding wires just to put the pm's into a bead for easier storage until the summer months where I was going to re-refine the material. I think there may have been a little bit of copper from ic chips caught up but I wasn't too bothered as knew I would be re-refining the material. When melting the borax I think I possibly started off with too much which didn't enable the metal to bead together in the centre of the dish as per previous experiences. Thanks for your suggestion of adding silver, I hadn't thought of this. What are your thoughts re tidying this dish up? Do you think its past the point of rescuing? I haven't had much experience with the melting of the pm's and I guess this is the sort of thing you learn as you go to a degree. Do you think also the fact that the dish wasn't sitting on an insulating pad, this would have had an effect?

Thanks again, Simon
 
If you have it available, try wrapping your dish with some kawool insulation to help hold the heat in the dish and you may get a better more even melt that way.

Ken
 
Thanks for your reply Ken, I will try this 1st next time I have some free time.
As I remember from my last attempt to sort out this mess the material would melt on one side of the dish and
in the middle but would then solidify on the other side of the dish, and as hard as I tried I could not get the
whole lot to melt evenly.
So my next attempt will have some insulation under the dish.

I think also a small dish may have helped my situation, O what fun!!

Simon.
 
I cut out a small section of insulation and then cut a small area the melting dish can be sat in. While its not cut to exact size, the dish sinks down far enough that its completely covered and makes all the difference.
 
Insulation helps, or putting a few firebricks up around the melting dish. A lot of the heat loss is by radiation and the firebrick kiln is helping reflecting that heat back into the melting dish.

Look at this thread for an example. The firebricks made a huge difference.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=61&t=19840
I melted 50g of gold with just an LPG torch without oxygen.

Göran
 
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