Hey all,

I have been doing extractions for a year now and I always use the trusty STB Tek that I have developed myself over time. I have been experimenting with different methods and one I can't get right is heat baths. I have tried 3 times to do it and all 3 times I have had the glass crack and wasted precious deemz! Would you please share some tips as I know how to extract and understand it well I just don't know how to warm it effectively. I use a 1L thick glass clip-top mason jar.

Make sure that the jar is near whatever heat that the water is when you place it in the water.

I tend to use a Ball brand jar, and my heat bath is always in a large pot. I also keep the lid on the jar relatively loose (but still on) in order to reduce pressure buildup which can contribute to the glass cracking and breaking.

As for the heat, I don't know the exact heat, but it's relatively low. It makes the soup and jar pretty warm, but I can still handle it with my bare hands. Out of 9 heat settings, I stay around 2.

One love

If the glass vessel is breaking due to temp stress I would say you are definitely using to much heat, I use a very thin walled glass bodum as the soup holder and have never had an issue.

I do my pulls at around 50c*. Colour varies from off white to yellow. Usually the first pull is nearly white but it get yellower on each subsequent pull.

To my mind this says that the temp is probably too hot. I am going to experiment with simply heating the soup and not the NPS as well as lowering temp to say 35-40c and see if that reduces the amount of oils that are also coming through.

When using the max ion tek I didnt use heat at all and nearly always got pure white xtals.

I must admit to being somewhat lazy with this step as after reading the thread on white/yellow/red dmt and the fact that theres very little difference between them I figured it wasnt worth putting that much time or effort into it.

*this is the temp my crockpot heats things to if using as a water bath.

Yeah, perhaps not only too much heat but, as Burnttoast22 suggests, also the wrong kind of glass - ideally you would use borosilicate (sometimes known as Pyrex™), and preferably thin material.

Many moons ago when I was a fresh spring chicken I had the bottom break off a large sweet jar in exactly your scenario: Wrong glass (soda lime), and too great a temperature differential between the heat bath, the jar, and the jar's contents. Fortunately - much as Voidmatrix also mentions - the pan for the hot water bath was large enough to hold the contents of the jar in addition to the hot water that was already in there, so nothing was lost.

This was the only time I had a jar break (not counting sheer clumsiness in the lab ofc) so I hope you're now attuned to the parameters for avoiding a third repeat of the thermal stress failure phenomenon. Or can at least ensure you use a large enough pan to save the extraction - a bit of dilution in the heat bath doesn't do it any harm. IIRC, the extraction continued fairly well from the large stainless steel pan, the only problem being the large surface area made naphtha recovery trickier and less efficient. And there are workarounds even for that.

Also not all soda glass is created equal. Im pretty sure my Bodum isnt Boro for example.

You also need to be careful with newer Pyrex as its not necessarily Boro glass anymore. When the company was sold or moved to the US they stopped using it across the range.

If you get pyrex glasss from the UK, particularly if it is a few years old then its almost certainly Boro.

I have used a borosilicate glass mason jar and still cracked lol I really want to try it again but it's so wasteful when it breaks and sad too haha. So if it breaks in a big enough pot then the soup is still usable yeah?

Unless the jar was compromised, boro glass should be able to easily handle 70-80C temp difference.

If everything was clean to start with and the pot contained only water (or even brine) then absolutely.