Maintaining Casting Crucibles with Janet E Alexander

Hand-held casting crucibles are used for casting in cuttlebone, sand casting, straw casting, and water casting. Before using a new crucible it must be prepared by coating the bowl and spout with borax. Over time, a used crucible becomes coated with too much borax and the borax can cause problems while casting. If the collection of borax becomes too thick in the crucible, it can cause a clog at the spout, or even pour into your mold blocking the metal from entering. This course shows the process of preparing and cleaning the crucible.
Janet is an accomplished metal artist with her work published in several books and magazines including on the cover of Lapidary Journal Jewelry Artist; The Gemmys 2015, Contemporary Metal Clay Rings. Her creations can be found in Metal Clay in Color, American Craft Magazine, Metal Clay Artist Magazine, Contemporary Metal Clay Rings, Metal Clay 101 for Beaders, and in New Directions: Powder Metallurgy in a Sheet Metal World.
For the past several years she has taught adults metalsmithing at conventions and gem shows. As a writer she co-authored, Metal Clay in Color, has written many tutorials for books and magazines.

[@chrismalcomson7640]

Thanks for the video. I do spin casting and there's actually a fairly small hole for the molten bronze to go through and the build up of borax over multiple castings causes a few issues. I usually just use a new cricible when it gets too bad but I'll give it a go..

[@JanetAlexanderJewelry]

I hope it worked out for you to clean the crucible?

[@MxC1337MxCsh43d]

Thank you! Your videos are underappreciated!

[@JanetAlexanderJewelry]

Thank you for watching!

[@JanetAlexanderJewelry]

Hi Julia, the borax coating always cracks. If it gets to thick. You might heat it and scoop out the excess and then re-coat the area.

[@joycejoy7651]

Thank you for the video, very helpfull

[@JanetAlexanderJewelry]

Thank you!

[@JuliaPeraltaL]

Hi! Thank you for making this video. I tried to prepare my own crucible with borax and is all coated but it started to crack, not the crucible itself but the crystallized borax is cracked. I don't know what went wrong. I want to know if its ok to use it like that and melt silver on it or if I should scrap the coating off (and how) and try to glaze it again?

[@seanfoltz7645]

OK, thumbs up as you explained the why behind the borax treatment. Follow up question since you seem to know your stuff - do you have to retreat the crucible periodically?

[@JanetAlexanderJewelry]

At times you will need to heat the crucible up making the borax fluid and scrape out the excess. Other than that there is no reason to retreat it. Sometimes, if the metal is really dirty you have to add some borax over the metal to get it to melt more easily.

[@spotlobac7694]

hi there , dont know if yoool get this, i had 1 crusible that had about a gram of gold bbs & sluff. wild idea was pour some warm aqua regia in it & let is soak. it works, recovered some gold & had a semi new looking ceramic that needed to be refluxed.

[@JanetAlexanderJewelry]

Wow, that's great to know! Thanks.

[@mich65ek2]

If a crucible had previously used as melting copper, can I still be able to melt silver with it? Would it contaminate the silver?

[@JanetAlexanderJewelry]

Yes, it can. If you are casting sterling silver though it won't matter because sterling has copper in it. But if you are casting fine silver, then some of the left over copper, in the flux, can contaminate it making it less pure silver. I have one crucible for gold, and one for sterling silver.

[@christophersanchez3213]

Interesting. I did this to a crucible I have and I had a loss of silver when I poured it.. the silver ended up on the walls almost like tiny dust.. I recovered some of it, I was tolled my flame may have been not hot enough or my silver was not clean.. I used a mapp gas torch from harbor freight... I guess I have to get a burns o matic torch..

[@TheWyoCoyote]

I wish I had known this. I had a guy give me a crucible and I melted brass in it. I did use some borax but it is all gummed up with glaze now and I can't get it off. I will try again, but I don't have a carbon stick.

[@JanetAlexanderJewelry]

Richard, you can purchase a carbon stick at www.ottofrei.com/Store/Kerr-Electromelts-Digital-Electric-Melting-Furnance-Melting/Carbon-Stirring-Rods.html for $5.

[@debbievine946]

Hi. How often do you have to coat your crucible?

[@JanetAlexanderJewelry]

I apply a coating only when its new. It never goes away and as you melt metal you add a pinch of borax over the top of the metal keeping the oxides off the metal. When you pour the metal some of the borax attaches to the crucible and spout. That's why over time it has to be cleaned out.

[@debbievine3334]

Debbie Vine thanks!

[@leilahankinson4498]

I found this video while searching for a solution to sky problem: I primed a new crucible with borax, which looked great all perfectly glazed. (I live in a very humid area) so...when I went to melt gold, I noticed the glaze was sticky so I heated up the crucible to re-glaze the glaze. it looked good again. well, then I started to melt a small amount of gold but the glaze melted faster than the gold and the gold got all gummed up and stuck inside the glaze! I realized I had too much borax in my original glaze application, plus my torch wasn't hot enough. so for those of you who are beginners, beware of priming your new crucible with too much borax to glaze it. then make sure your torch is hot enough to melt gold. if you get metal trapped in glaze, wait till it cools, then melt the glaze with water and your metal will be released!

[@JanetAlexanderJewelry]

Yes, that is when you would use the carbon stick to remove your metal and then scrape out the excess borax.

[@JanetAlexanderJewelry]

Yes and no. .. the borax is used to coat the crucible so that there is a glass like coating over the ceramic material. It never needs relocating. Then, also it is used for cleaning oxides off the molten metal. If you are melting used metal, or tarnished metal there will be reddish floating stuff over the metal when it's completely melted. Sometimes just stirring it with a carbon stick will cleaned/push it to the crucible sides. But sometimes you have to put a pinch of borax on the metal while stirring it, to remove the oxides. Over time the borax becomes too thick and then needs scraping out while the crucible is hot..

[@chrismalcomson7640]

I use borax to help the metal flow. A little pinch of borax helps the metal melt. Before casting I use an old needle file to drag any slag to the back of the crucible so it doesn't interfere with the flow..

[@danieltingstad857]

does boric acid work the same as borax?

[@JanetAlexanderJewelry]

+Daniel Tingstad, Hi Daniel, no boric acid doesn't work the same.