Thanks, Roy! I melted the wax cut-offs and the sheets look like the new ones. Nice that you can make them according to whatever thickness and size you need.
If anyone wants to try this, here are some observations. I know some are obvious but it may help if you do this in a rush at the end of a full day :)
Wax: Kemdent Anutex dental modelling wax (about 250g of fairly clean off-cuts, any plaster remnants were scraped off)
Tray: with a 16cm x 25cm tray I got 3 trays worth of new wax strips with about 2mm thickness. Make sure your lab tray is smooth and the surface is levelled.
Lining: you could re-use the paper that separates the wax strips in the box to line your lab tray or baking paper. Although, baking paper may crinkle when wax gets poured onto it, and you lose the straight surface needed to make detailed moulds (you can still use the other side though but it can be greasy). So, I tried one batch without any lining and even if removal was a little trickier, it worked well with my tray once the wax hardened fully. I may try this on a matt silicone sheet next time for a less glossy wax strip.
Meltinginwater bath/bain marie (about 15-20 minutes over simmering water). Please check the safety data sheet for your type/brand of wax to ensure it does not ignite at temperatures subjected to during melting.
Pouring: the wax can be sieved if needed but I skipped that as my wax pieces were fine (and the wax would not be in direct contact with the object anyway in our case). That way loss of wax was avoided, plus no need to clean too much equipment afterwards.
Curing: The wax hardened really quickly, within about 15min it kept its shape but I let it cool completely before removing it from the moulds. Like the new sheets, they keep their shape really well and soften after gentle heating with a hairdryer, and there is no funny oil film or anything going on (as of yet)
Preparation of cut-offs, tray and new wax strip (left); remelted/newly cast strips cut to size (right)
"Depends on what kind of wax it is I guess. If it's ordinary paraffin wax or reasonably close, use could use it to: make furniture polish, wax the undersides of wooden drawers, ditto the sides of old-fashioned sash windows."
Thank you, Ariana, for sharing Etym Dub's suggestions. I'll keep them in mind for when we have troubles with our sash windows or drawers in the studio! (The wax we use is Kemdent Anutex dental modelling wax, by the way)
When literally restoring tons of ceramic on excavations in Romania I came up with the following extremely easy recycling technique:
- First get a big bowl and fill it with very hot water from a kettle.
- Pour in all your wax scraps and stir properly. The wax will melt and any rests of plaster etc. will sink to the bottom while the molten wax will be floating on the surface of the water.
- Let it sit for a while to cool to room temperature. As soon as the water cooled down, you will have a new wax plate covering the water like ice on a frozen lake.
- Cut it near the bowls rim and you will have a new wax plate with one rougher side (the one facing the water) and one smooth side that you can use to back new fillings.
One more tip: If there are flies around, you might want to cover the bowl when it is cooling. They are magically attracted by the wax and drown in there.
The method does not produce as clean and impressive results as your remelting. But it was very fast and the results were good enough for us. We reused the same wax again and again even for multiple campaigns and it worked fine. I even made some really thick and huge plates to back some plaster fillings on a large vessel (about 1m height). So if you are on an excavation in the middle of nowhere, this could be your method :)
Thanks a lot for sharing this method @Alex Dittus. I'm very keen on trying this next time we have a collection of wax cut-offs and will report back how it went :)
I think from a safety point of view it is better to use a double boiler to melt wax to avoid sudden fire/explosion. I think it is something to do with flash point - I'm not a physicist. But you can DIY these fairly easily from things you are likely to have already and there are instructions all over the internet.
Thank you very much for the safety tip. The safety data sheet for Kemdent Anutex HS Modelling Wax mentions "when heated above 150°C will burn whilst heat source available" so the waterbath/bain-marie is definitely the way to go. I added the safety tip to the post above!
Have you tried remelting them and cast new sheets?
Thanks, Roy! I melted the wax cut-offs and the sheets look like the new ones. Nice that you can make them according to whatever thickness and size you need.
If anyone wants to try this, here are some observations. I know some are obvious but it may help if you do this in a rush at the end of a full day :)
Wax: Kemdent Anutex dental modelling wax (about 250g of fairly clean off-cuts, any plaster remnants were scraped off)
Tray: with a 16cm x 25cm tray I got 3 trays worth of new wax strips with about 2mm thickness. Make sure your lab tray is smooth and the surface is levelled.
Lining: you could re-use the paper that separates the wax strips in the box to line your lab tray or baking paper. Although, baking paper may crinkle when wax gets poured onto it, and you lose the straight surface needed to make detailed moulds (you can still use the other side though but it can be greasy). So, I tried one batch without any lining and even if removal was a little trickier, it worked well with my tray once the wax hardened fully. I may try this on a matt silicone sheet next time for a less glossy wax strip.
Melting in water bath/bain marie (about 15-20 minutes over simmering water). Please check the safety data sheet for your type/brand of wax to ensure it does not ignite at temperatures subjected to during melting.
Pouring: the wax can be sieved if needed but I skipped that as my wax pieces were fine (and the wax would not be in direct contact with the object anyway in our case). That way loss of wax was avoided, plus no need to clean too much equipment afterwards.
Curing: The wax hardened really quickly, within about 15min it kept its shape but I let it cool completely before removing it from the moulds. Like the new sheets, they keep their shape really well and soften after gentle heating with a hairdryer, and there is no funny oil film or anything going on (as of yet)
@Julia Johanna Wagner
so cool how that worked out! Well done ✌️
From Etym Dub on Twitter:
"Depends on what kind of wax it is I guess. If it's ordinary paraffin wax or reasonably close, use could use it to: make furniture polish, wax the undersides of wooden drawers, ditto the sides of old-fashioned sash windows."
Thank you, Ariana, for sharing Etym Dub's suggestions. I'll keep them in mind for when we have troubles with our sash windows or drawers in the studio! (The wax we use is Kemdent Anutex dental modelling wax, by the way)
When literally restoring tons of ceramic on excavations in Romania I came up with the following extremely easy recycling technique:
- First get a big bowl and fill it with very hot water from a kettle.
- Pour in all your wax scraps and stir properly. The wax will melt and any rests of plaster etc. will sink to the bottom while the molten wax will be floating on the surface of the water.
- Let it sit for a while to cool to room temperature. As soon as the water cooled down, you will have a new wax plate covering the water like ice on a frozen lake.
- Cut it near the bowls rim and you will have a new wax plate with one rougher side (the one facing the water) and one smooth side that you can use to back new fillings.
One more tip: If there are flies around, you might want to cover the bowl when it is cooling. They are magically attracted by the wax and drown in there.
The method does not produce as clean and impressive results as your remelting. But it was very fast and the results were good enough for us. We reused the same wax again and again even for multiple campaigns and it worked fine. I even made some really thick and huge plates to back some plaster fillings on a large vessel (about 1m height). So if you are on an excavation in the middle of nowhere, this could be your method :)
Thanks a lot for sharing this method @Alex Dittus. I'm very keen on trying this next time we have a collection of wax cut-offs and will report back how it went :)
I think from a safety point of view it is better to use a double boiler to melt wax to avoid sudden fire/explosion. I think it is something to do with flash point - I'm not a physicist. But you can DIY these fairly easily from things you are likely to have already and there are instructions all over the internet.
Thank you very much for the safety tip. The safety data sheet for Kemdent Anutex HS Modelling Wax mentions "when heated above 150°C will burn whilst heat source available" so the waterbath/bain-marie is definitely the way to go. I added the safety tip to the post above!