Vac oven purge problems.

I’ve been having problems getting a nice sugar crumble consistency with my bho. I’m using a vac oven and I average about 200g after purge. Sometimes I’ll get a nice sugary wax on parchment and also a good crumble in Pyrex but other times it will just flatten out and turn into goo. Am I putting to much bho extract in my Pyrex? I’ve been reading alot on it but only to find mixed reviews about it. Any advice would be appreciated. I’ve been playing with different Temps and vac but I’m starting to feel a bit lost. I don’t go under 90 or over 120.

  1. Try the search feature…
    Search results for 'sugar' - Future4200
    Search results for 'nucleation' - Future4200
    Search results for 'butter' - Future4200
    and maybe even Search results for 'shatter' - Future4200

you’ll need to look deeper that the 1st hit.

  1. what are you doing before getting to the oven? Making goo sounds like you started with partially decarbed material, or over heated during recovery. Going into the oven in Pyrex suggests you might be open blasting. Tell us what you’re running & how.

I am running a closed loop MK4C terp extractor. I freeze the packed columns in a cryo freezer before blasting. I have a partner doing the blasting so im worried that the problem is starting with him. We run 10lbs of solvent(twice) through the column to soak for about 15 min before dumping into bottom pot, so about 30 min soak time between two 10lb blasts. The bottom pot of the terp extractor is in warm water to help evaporate the solvent. Once the run is done ill take the Butane rich Bho and ill usually whip it pretty well before pouring into pyrex or parchment. After this is done ill place bho into my vac oven and pull vacuum with a temp at 100-110.

Also, Sometimes when i get the freshly extracted bho (before oven) it comes out dry and hard, what does this suggest?

In my experience with crumble, Some material dries out faster than others and requires lower whipping temps. Ive always felt the terp profile is partially responsible for gooey texture too. My fruitier material usually wants to be more gooey and the more earthy flavors dry out nice as crumble. A good rule of thumb would be anything that makes nice stable shatter will make a good crumble. I muffin the crumble in my oven at 90 degrees Fahrenheit and that temp seems to work really well. I also start whipping at about 108 then slowly increase to about 120. A double wash and soak sounds pretty extensive though, you might be picking up some water solubles. I do a 3 to 1 ratio solvent to material, single wash and no soak. Your yield might drop a little doing it this way but the color quality should be better and you’ll get less undesirables in your final product.


Thankyou for your response! when you vac down to get your muffin are you fully vacd?
When you whip at 108 are you saying you’re slowly bringing it up to 108 after your muffin stage and then breaking vac to whip?

I get up to about 10 inHg before i have to stop my vac before it muffins over the sides

the first thing it suggests to me is that the temperature of your warm water is not well controlled.

As @Merakian_Hash states, the individual terpene profile will also change how quickly your products firm up.

“Sap”, if it meets state mandated residual solvent levels, and contains appropriately low amounts of THA (vs THCA) is a terpene based phenomenon.

Different strains, produce different mixtures and absolute levels of terpenes. As a rule, the C10 mono-terpenes are easy to boil off, the C20di-terpenes less so, and C25sesterterpenes are even harder to remove.

I have a CBD chemovar that produces sap. I can get it to firm up, but that would just mean boiling off terpenes.

Edit: seeding in addition to whipping might have some utility…


I whip first starting at about 108 then work my way up as needed. I just pay attention to how much the wax is responding to whipping. when you find that less reaction is happening thats when its time to bump it up a bit. As it gets close to buttering then ill put it in the vac at 90 and pull vac to about 15inhg or 20inhg. What I really aim for is getting the largest muffin I can without letting the bubbles pop and deflate the muffin. If that happens take it out whip it again then try the muffin tech again. It should eventually work but after too many tries it won’t muffin anymore., and you’ll get less of a honeycomb and more of a brick of crumble. After you get the muffin to hold let it sit for about an hour and let it dry out then I usually pull full vac and let sit for an additional 2 hours for good measure. 2 hours might be a little bit of an over kill but thats up to you to decide if you think the product is finished or not.

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I have this muffin at 90 degrees at 20inhg. There isn’t much reaction going. Should I slowly raise the temp? I’m hesitant to do so because I don’t want goo.

don’t raise the temp. give it time and it should dry out. but keep an eye on it incase it starts to deflate. It looks like it could have used a little more whipping but its hard to tell. I also whip and muffin inside a 9 inch round pyrex. Ive never done a muffin on parchment.

how does it look right now?

it looks the same. i can see bubbles in the muffin and it looks more wet than dry

maybe different with parchment?

let it sit. it should still dry out like that. I don’t think its the parchment. I think maybe it need a little more time whipping. how high did you et on the temp when you were whipping? also what strain is it?

Ive seen someone not even whip and just knead and twist and just get the wax into a shiny lighter color then throw it into the oven and i watched it get 2-3 inches thick. How would I do that? Unfortunately I can’t get this information anymore