I have just bought an old chamber pot made by Royal Doulton for not a lot of money. I'd love to use it as a planter, but the glaze has crazed, but not too badly I'm thinking that it's cast earthenware, with a plain white glaze and no decorations of any kind.. What would happen if I popped it on stilts and took it slowly up to temperature? Anyone any idea whereabouts that temperature might be?
I've often come across interesting pots with crazed glaze, but never been tempted to try this before. Thanks for all your help.
Hi Susie, with the accummulation of dust and grim sitting in the crazed sections(even if it looks clean) of your pot I would say refiring will not help in any way.
If you attempt this, I strongly recommend that you go VERY slow at the start. If it is earthenware, the pot almost surely has moisture trapped inside it, which will not come out simply by sitting around at room temperature. If you raise the temperature too fast, you'll have a lot worse than crazing!
In fact, you might want to use your kitchen oven for this. Start out with an hour or so on "low" (under 200F) and work your way up to (say) 350F over a few hours. I used this approach on a friend's earthenware mug that always got hot in the microwave. I suspected trapped water, and this approach indeed "cured" it... at least until the next time he washed it!
Which brings us to the fact that despite your best efforts at reglazing, you pretty much have to assume that water will somehow find a way into the body, which may very well cause new crazing down the road.
Nevertheless, this might be a fun project and if you take it slow you don't have much to lose but the pot. As far as re-firing temperature, I'd keep it under cone 04 if you don't know anything about the body. If that doesn't heal the crazing and you are still interested, maybe go to cone 1 or
2 max, watching through the peephole for signs of sagging.
Please report back here if you try this!
Best regards,
Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis
formatting link
Scope, Spectrum, Spectrogram, Signal Generator Science with your sound card!
I have a kiln with a firing ramp starting 25/40/60deg per hour. I should be able to crawl at low temperature for quite a while and then creep up the range. This should stop the thing heating up too quickly and, as you put it, gives me worse problems than just the original crazing. The kiln cuts in to full power at 600degC. My kiln's a top loader, so there's no way of checking through peephole for problems. Time to play safe at the lower temperature, if I go ahead and try this.
I suppose on other way of going about this is to seal the inside of the pot with one of the polyeurathene varnishes. Probably a safer approach, but not as much fun. Any recommendations, please. From what you say Bob, I will probably have to do this after firing anyway.
Of course, Bob, I'll let you know what happens if I do fire it.
Going back a few decades, I bought a couple huge old platters at an auction. They were badly crazed, cost near nothing. I fired them in a very slow bisque fire. I always do hours and hours slowly firing, and rarely if ever, lose anything. Anyway, the platters came out beautiful and looked sparkling new. I was amazed, never expecting such remarkable results. I wish you equally fine luck with your piddle pot. ;- )
InspirePoint website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.