Vacuum Purging Winterized Oil

After removing most of the polar solvent (I use etoh) from the oil at a warm air fan purge, can too high of a vacuum decarb the oil even at lower temps <105F. I see lots of decarb bubbles and a few larger solvent bubbles, but not sure if this is making it harder to get shatter or easier? I run a 6cfm vac that pins out on my gauge at 30Hg. Would I be doing myself a service by getting a bleed-off valve and lowering my Hg for this step of the process to something more gentle (just enough to pull solvent bubbles)?? Or is it just a bad idea to vac winterized oil at all? Any thoughts???

You are boiling the THC away at room temperature at full 29.92" Hg vacuum. We use -29.5" Hg max.

Winterizing makes a more concentrated and smoother vaporizing oil, but with less monoterpenes. Long term, I prefer winterized oil to vaporize, because it is easier on my lungs and still tastes damn good.

Fadedawg said:

You are boiling the THC away at room temperature at full 29.92" Hg vacuum. We use -29.5" Hg max.

Winterizing makes a more concentrated and smoother vaporizing oil, but with less monoterpenes. Long term, I prefer winterized oil to vaporize, because it is easier on my lungs and still tastes damn good.

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How do you modulate the pressure to keep the vacuum stable at -29.5"? I have heard of some people leaving a valve on their vac ovens open a just a crack and getting more flavorful results, but I don't imagine that is a good long term course of action for your pump.

mrcryce said:

How do you modulate the pressure to keep the vacuum stable at -29.5"? I have heard of some people leaving a valve on their vac ovens open a just a crack and getting more flavorful results, but I don't imagine that is a good long term course of action for your pump.

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Not sure about the best solution for a vac oven but for a chamber with pump you can just buy an adjustable pressure relief valve and that will allow you to lower your Hg . I am using 6CFM 2stage pumps that may be a bit overkill but we got really good deals on them so it was hard to resist, but with winterized stuff I feel its much more easy to pull terps than it is when purging butane (at least until you have passed that wet unpurged BHO shatter stage). So I feel the need to make sure i'm not pulling too hard of a vac.

mrcryce said:

How do you modulate the pressure to keep the vacuum stable at -29.5"? I have heard of some people leaving a valve on their vac ovens open a just a crack and getting more flavorful results, but I don't imagine that is a good long term course of action for your pump.

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Cracking the vent at the oven works well, and allows the aspirated air to act as a gas ballast as well.

mrcryce said:

How do you modulate the pressure to keep the vacuum stable at -29.5"? I have heard of some people leaving a valve on their vac ovens open a just a crack and getting more flavorful results, but I don't imagine that is a good long term course of action for your pump.

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An analod gauge does not display enough resultuion to truly tell the difference between 29.5 and 30" Hg. Here is a link to a good vacuum pressure comparison chart. http://www.engineeringtoolbox.com/vacuum-converter-d_460.html

Check out the comparison of % vacuum to "Hg. Vacuum is not a linear scale, it is logrithmic os you can see how important very small increments are as you go lower and lower in pressure. The only way to truly moderate the base pressure of the system asside from a precision gauge-controller feedback loop is to source a pump that has a base pressure consistent with your desired vacuum level. For this application, we reccomend a pump that has a base pressure fo 1.5 Torr. This means that no matter what--gas load, temperature, oven size--the pressure will not get lower than that. Trying to choke a dual-stage rotary vane pump with air will displace oil into your environment and ultimately destroy the pump.

An interesting point. Instead of trying to control vacuum levels measuring with an analog gauge calibrated to 29.92 divisions for one atmosphere, Torr break one atmosphere down into 760 parts, and microns down to 760,000 parts, which is also where millitorr takes us. We operate in the rough vacuum zone, but using Torr or Millitorr instead of in/Hg, makes nuances easier and we don't have to crowd in as safety margin.

1.5 torr is about 29.86" on an analog gauge, which would be pretty hard to read, so a Torr/militorr, or micron gauge would be required. At that point, THC still boils above 110F, so it will still work, and the reason that I picked -29.5" Hg, instead of -29.86" Hg, is for safety margin using crude instruments. At -29.916", it boils at 62F and at -29.919 at 23F.

CT, do you have links to any budget minded digital Torr meters, that ma and pa might use to retrofit their ovens and chambers, as well as to ones more oriented toward the commercial community?