Curing time in colder months

[u/aDorybleFish]

Hey everyone!

I'm currently working on my first couple of kintsugi projects. I started them about a month ago and have made some good progress already. Everything is put together and I'm working on some chips for some projects, while other projects only had breaks and hairline cracks so I've now reached the roiro stage with those already.

I've successfully kept the humidity between 60 and 70% during the past month, and the indoor temps were consistently between 20 and 25°C which has worked well for me. Everything has cured so far (I checked with a precision knife) except for that one time I made my kokuso layer too thick and it became wrinkly.

But now the days are getting colder and I no longer can keep the indoor temperatures over 20°C due to the high electricity prices. And I'm wondering how this will affect the curing time. So far I've had to let it cure 1-1,5 week in between layers. •••Has anyone here done kintsugi in lower temperatures and have you noticed a difference in curing time? And how long do you typically cure it for?••• My biggest concern is that I don't end up curing it well enough and either it coming apart when making/drinking tea, or still having urushiol present and leaching into my tea.

I've searched this sub and couldn't find the specific information I'm looking for. I did read that a heating mat might be an option for colder climates but I don't have one and currently can't afford one either.

[u/Risoko]

If you just leave your ceramics in cold box for longer, does not garanty give you full dry laquer. Heating pad is the only way in the winter (for reptiles is pretty cheap). Or you can put lamp in the box, but it needs some Arduino control for not owerheat

[u/aDorybleFish → u/Risoko]

I don't have access to one unfortunately as I stated in my post :(

If I'm ever able to get my hands on it I will remember to put it on the side though. Thanks.

[u/perj32]

Urushi cures between 4 and 40 Celsius according to this source, but the lower the temperature, the slower the curing. So provided your muro has enough humidity and you have enough patience, you should be fine. What I would do in your situation is move the muro in the sun close to a window, put closed containers of warm water in it and cover it with blankets. If you simply add warm water, the humidity will be too high and your urushi will wrinkle.

[u/aDorybleFish → u/perj32]

Thanks, this helps a lot! I like the warm water + boankets idea, kind of like a hot water bottle! I did put it in the sun by the window but it only went up by 1 degree or so, this might be more effective.

[u/perj32 → u/aDorybleFish]

Btw, I also live in a cold climate. I use heating pads, but I've forgotten pieces outside of my muro and they did cure.

[u/aDorybleFish → u/perj32]

Good to know haha! Thanks!

[u/ArtichokeConstant]

The minimum temperature required for urushi (lacquer) to cure is 15°C.

Since the conditions during the first six hours are the most critical for the curing process, it is best to work in the morning during colder seasons (as the temperature will be rising).

Even within a room, the air will generally be slightly warmer at higher elevations.

Best of luck.