Hello nexians, I as many of you sometimes don't have enough time or just don't feel like taking a whole weekend for doing multiple boils and reducing over and over while stinking your whole place.
So I put together this setup to have my bark sitting in an acid bath at high temperatures for an unlimited amout of time. Now, I this setup is not designed to reach boiling temperatures because it would require constant attention and refiling of water thus rendering eliminating the unnatended part.
The setup is very simple and can be put together easily, it needs the following, the most expensive part is the cooler but most of us have one already:
40lt or higher capacity cooler - $20 - $50
Digital temperature controller - $12.50 (ebay)
Immersion water heater (bucket water heater) - $1.50 (hardware store)
Mischelaneous Cables and plugs - $10 (electric parts store)
Power Outlet
All you have to do is put your shreded/powdered bark in a large glass jar with lid and add your acidified water to it, close the lid and just put it in the cooler that has been filled with water and with the water heater and temperature sensor already installed. The temperature controller will take care of turning on and off the water heater to maintain the programmed temperature, I programmed mine to keep it 65-75ºC, I wouldn't recommend getting near 80ºC because the water alreay starts to boil above 80ºC and you don't want any accidents with over-pressure even though the cooler is not sealed it can still acumulate pressure.
I will let it sit for a few days or maybe a week or two and let you know how it went. If you need detailed instructions or have questions on how to put it together let me know and I can post a more detailed guide.
Here are pictures of my setup:
You can see here the jar with the bark floating around, the water heater and the temperature sensor: