I'm using a Vcella TL16 tilting furnace with a graphite crucible, idk if it has the same properties as the large crucible seen here.
http://www.lmine.com/mm5/merchant.mvc?S ... ng_furnace
I'm using the following in my melts of various copper alloys. Most alloys consist of either a copper zinc or copper lead variety.
Brass Flux Synex - BA315 - http://www.budgetcastingsupply.com/Brass_Flux.php
15% Phosphor Copper Shot - http://www.budgetcastingsupply.com/Phosphor-Copper.php
Brass Degasser - Asbury 761 - http://www.budgetcastingsupply.com/Brass_Degas.php
I put in some Flux at the start before a charge is added to help the metal form a heel. After the metal is melted I add some Phosphor shot, Flux, then degasser, then pour. However, I was shipped something that was suppose to be Brass Degasser - Asbury 761 but it may have been plumbago I simply cannot tell the difference it does react in the furnance as the degasser should. When I am done with my furnance I am noticing a thick black substance on the crucible walls, that when I touch it flakes off. It looks almost like sweat on the inside of the crucible. The crucible has about 12hrs use on it. It looks like it may last 30-50hrs total. The outside of the crucible is 100% ok, the inside is looking like 75-80% ok it just looks like it needs to be cleaned and then patched in some ways or coated to prevent this from happening anymore.
Possible Solutions: (Which should I do?)
Cut down on amount of flux, and degasser used.
Use ITC 213 on the inside of the crucible. The same stuff I coat my skimmers with - http://www.budgetcastingsupply.com/ITC.php
Try using some Buffalo Patch on the inside of the crucible - http://www.lmine.com/product/17152X.html
Also what should I do to a new crucible to help it out and prevent chemical damage to it?
How do I clean the inside of the crucible without damaging it, and with what?
http://www.lmine.com/mm5/merchant.mvc?S ... ng_furnace
I'm using the following in my melts of various copper alloys. Most alloys consist of either a copper zinc or copper lead variety.
Brass Flux Synex - BA315 - http://www.budgetcastingsupply.com/Brass_Flux.php
15% Phosphor Copper Shot - http://www.budgetcastingsupply.com/Phosphor-Copper.php
Brass Degasser - Asbury 761 - http://www.budgetcastingsupply.com/Brass_Degas.php
I put in some Flux at the start before a charge is added to help the metal form a heel. After the metal is melted I add some Phosphor shot, Flux, then degasser, then pour. However, I was shipped something that was suppose to be Brass Degasser - Asbury 761 but it may have been plumbago I simply cannot tell the difference it does react in the furnance as the degasser should. When I am done with my furnance I am noticing a thick black substance on the crucible walls, that when I touch it flakes off. It looks almost like sweat on the inside of the crucible. The crucible has about 12hrs use on it. It looks like it may last 30-50hrs total. The outside of the crucible is 100% ok, the inside is looking like 75-80% ok it just looks like it needs to be cleaned and then patched in some ways or coated to prevent this from happening anymore.
Possible Solutions: (Which should I do?)
Cut down on amount of flux, and degasser used.
Use ITC 213 on the inside of the crucible. The same stuff I coat my skimmers with - http://www.budgetcastingsupply.com/ITC.php
Try using some Buffalo Patch on the inside of the crucible - http://www.lmine.com/product/17152X.html
Also what should I do to a new crucible to help it out and prevent chemical damage to it?
How do I clean the inside of the crucible without damaging it, and with what?