I have been thinking about a way to make an affordable freeze dryer. An old vac oven seems like the best Starting point. Has anybody atound here ever made a freeze dryer from scratch or converted a vacuum oven?. I’ve looked into autoclaves as a vessel as well as stainless kegs vs welding up my own but bang for the buck seems to be an old vacuum oven hooked up to a chiller.
1 Like
Technically I think all you need is dry ice and a vacuum oven… the heated shelf ones are best.
Since the physics of it you are reducing the boiling point of water, then you freeze the product beyond the freezing point of water and sublime it under reduced pressure.
4 Likes
@PharmExOregon makes some nice candies. Took can’t make it really a freeze dryer without cooling, but you can kind of do it.
3 Likes
You can turn one into one by slapping some heat mats under ur shelfs and wiring it thru a vacuum/pressure proof wire connection to get it outside.
Prefreeze ur stuff in any freezer, throw it in, pull full vac, then start cycling ur heat mats
5 Likes
it can’t be any worse than a harvest right. Lol. Pretty much dead set on doing this. If anyone wants to donate some vac ovens to the cause we can work out a deal. Somebody has to have done this before this idea seems insanely generic but I havnt found anything on YouTube or Google Or at my local chiller services shops that have actually done this yet.
2 Likes
Add a LN2 cold trap to catch the water or use an oil-less vacuum pump. Otherwise you will be changing the oil pretty often.
3 Likes
I have a Poly science heater chiller that would work great for this and would also provide a defrost mode between runs
Like a metanol cold trap out the back. Like one of the BR instruments setups
U only have to defrost if ur using the outside walls as ur “water catch” like the harvest rights do. Once u heat the shelfs and the “exterior” the only place for the water to settle is outside ur chamber
realistically Ill just just run 2 or 3 of my glass cold traps just for terps that get sucked through
1 Like
Technically the terpenes will come off after the water… higher boiling points, just more volatile, so if they are not making vapor the lowest boiling point substance should sublime first. Have heard pretty damn good results with freeze dried terpene retention.
Not much of a steam distillation taking place under vacuum with sublimation so vapor pressure shouldn’t carry much over.
2 Likes
Just make one of these shit boxes and throw some dry ice in the fish tote
1 Like
Making candies is simple with a freeze dryer, you dont even need to use a freeze dryer, just vacuum the candies and you can watch them expand and dry out.
If you pre freeze material, your material will stay cold as long as the vacuum levels can stay low. the trick to this is having a sufficient sized ice trap and proper vacuum, dry scroll is the best.
I have been freeze drying flash frozen flower with great results, the water doesnt smell like terps and the tests have come back at 3-5% terps. My freeze dryer does not have directly heated or cooled shelves and my temp probe that touches the material shows the flower stays below freezing until the drying process is complete even when my temp profile is having the jacket at 20c.
2 Likes
Pictures worth a 1000
I have an ice trap isolated so I can keep the main chamber under vacuum while I thaw the ice enough to knock it out of the trap.
Using an Edward’s XDS46i vacuum and do 50-70lbs wet at a time.
Just realized the phone didn’t capture the pid read out but it’s currently at +14c in the chamber. And material is below 0c
8 Likes
Come on down and grab some ovens, im looking at getting one too just dont wanna buy a new harvest right.
3 Likes
I have a prototype built out of a keg thats basically the same thing. Id like to be able to dry more than an lb at a time tho . That bvv setup looks like it might dry a nug from time to time. Lol
1 Like
Got any more pics , looks roughly like what im shooting for.
Sorry for the dumb question, but can you make freeze dried candy and double mushrooms extractions with the same machine? I want a freeze dryer for extractions, and my wife said to jump on it because she wants to make candy. I didn’t know if like flavors from the mushrooms would some how stick around in the system and give a nasty taste to the candy.
I know this is too small scale for you but my first r&d freeze dryer I built from one of those cheap amazon/ebay vacuum chambers. If you can figure out a vacuum oven that allows for flowing through the shelves or if you can add heating/chilling lines from copper and seal them maybe that could work? I had this hooked up to a heater/chiller so I had the -20F to +30F range that I was looking for. I ultimately got tired of chasing vacuum leaks and picked up a harvest right instead. Very interested to see if you get this going OP.
1 Like
Like @thesk8nmidget said, you don’t need a freeze dryer to make “freeze dried” candy. Just a normal vac oven with a cold trap to catch the moisture you remove. It’s probably same for the mushrooms but I haven’t tried. Smell crossover should be a non-issue if you clean the oven and cold trap inbetween runs.
Here is some candy we did in a vac oven at 135f/58c for an hour.
4 Likes