anyone ever make their own Freeze dryer?

[jeanw]

If my one younger BELOVED brother was still alive Im sure he would have taken the challenge
any comments on Freeze dryers or anyone ever made their own?. I dont know why the units/// have NOT come down in price (pre depression days{ since I first heard about them. , I have only seen videos. and heard radio commercials so etc. never seen a unit in real time, Thanks all again

 

[Corey]

To do it right, you're going to need a modest sized vacuum chamber, vacuum pump, piping, control system, cold traps/moisture removal... oh - and a freezer to keep it all cold. Not that it can't be done, but vacuum pumps/chambers/etc are slightly elevated levels of DIY. You could probably get by with a freezer and a bag of desiccant, but that is really slow and not truly 'freeze drying' where you are actually subliming the water directly to vapor.

I think a lot of this stuff is 'mature' technology so pretty stable in price. There is not much you can do to make a cheaper vacuum chamber or control valve. At least not in the way you can make a cheaper Rolex by having it made in china.

 

[Dan Freeman]

I skipped the DIY and bought a Harvest Right FD 2 years ago. One of the best investments I ever made.

 

[Ashful]

$4k to $6k. I love Astronaut ice cream as much as the next guy, but... damn!

j/k... I know you prep'ers have loftier goals than my bricks of Neopolitan.

 

[Dan Freeman]

$4k to $6k. I love Astronaut ice cream as much as the next guy, but... damn!

j/k... I know you prep'ers have loftier goals than my bricks of Neopolitan.

LOL. Astronaut Ice Cream....NOT! Try veggies, meats, and fruits for long term storage. I am not interested in FD'ing ice cream, skittles, and Jolly Ranchers. We have FD'd over 500 lbs. of fruits, veggies and meats (bought on sale or grown by us) in the past two years and are not paying the outrageous prices for these products being charged right now, nor will we pay the higher prices or have a lack of food as the S continues to HTF. We just FD'd a bunch of potatoes and tomatoes this week. Will be doing more tonight. I have onions, turnips and beets lined up to FD over the next couple of days, all of these from our gardens. Eating like Kings and Queens for a fraction of what the stores/restaurants are charging. Our FD has already paid for itself, and it's all "gravy" after this.

 

[Ashful]

To each their own. I never have met a king or queen, but from what I read, I don't picture them eating much freeze-dried food.

Are you including the cost of electricity consumption of the device or your time in your calculations? I could understand ignoring your time, if you do it as a hobby or if you're salaried and your time doesn't cost you anything. But those things must suck some juice, given the few I checked require a dedicated 20A circuit.

 

[Dan Freeman]

To each their own. I never have met a king or queen, but from what I read, I don't picture them eating much freeze-dried food.

Are you including the cost of electricity consumption of the device or your time in your calculations? I could understand ignoring your time, if you do it as a hobby or if you're salaried and your time doesn't cost you anything. But those things must suck some juice, given the few I checked require a dedicated 20A circuit.

Didn't anyone ever tell you that sarcasm is a very low form of wit, but the best most folks can do when they don't know what they are talking about.

We will be eating like kings and queens when others are on a food line.

Yes, cost of electricity is figured in. It's only a couple of dollars per load. I don't know where you are getting your information about FD'ers. Time, well that doesn't matter much since it is set and forget. Nothing to do until the food is ready to come out. (No, this is not a hobby, nor are we salaried. We are just doing our preps.) Then, we put it in 7mil Mylar bags with a 300cc O2 absorber, heat seal it, and store it. Properly stored and rehydrated and you can't tell the difference from food that was just bought today, but for some reason many folks don't want to believe this. Oh, well...

You seem like you just want to be against buying a FD. (?) Perhaps you need to do more research, or you are just "cheap" like so many folks I see on this forum.

 

[Ashful]

Not against it at all, Dan. I don't see much point in it, or understand exactly what folks have been "prep'ing" for since the 1950's. But have fun with it, if it's your thing.

 

[EbS-P]

I’ve been starting to plan for a 3-5 week camping road trip. Cooking takes to much time and cold storage space for food. This is interesting. Figure feeding 7 for 10 meals a week for 4 weeks. Wonder if I could get them to eat MREs? Save at least one or two store runs a week and an hour a meal prep time. Couple that with the fact we don’t eat like your average American.

You know if I could find a a scout troop to split the cost with me……. Or maybe Uncle John’s wants to prep for the the big one….

Maybe I should buy/lease the empty lot down the street and build a big green house and garden? Soil is crap and I’m not sure I want to work that hard but like the idea

 

[Ashful]

It'd be interesting to see the break-even point on buying your own freeze dryer, EbS-P. I'm guessing for one 3- 5 week trip, you're still falling on the side of buying the food already FD'd. I'd bet Dan already has a number, it sounds like he's done the math on it.

... and I wasn't kidding when I mentioned Astronaut ice cream. I love that crap. I still remember when they changed from the expanded form of the 1970's to the more modern dense brick you can buy at the Smithsonian Air and Space museum today. Buying my own freeze dryer, specifically for making that treat, is an idea I probably first had around age 6.

 

[EbS-P]

Back to the OPs original idea. A decent sized vacuum vessel that would fit in your freezer and a pump. Sure I think it could be DIYed. Once below 0C it just sublimates anyway. I don’t see any pressure control needs. Only concern would be plugging lines due to vapor condensation and re freezing. No danger won’t ever extend -15 psi. I don’t know what pressure you should target but bigger pump will be faster.

Edit*****
I didn’t really think about how to do a quick flash freeze or how important it might be.

 

[EbS-P]

My ignorance on the topic needs to be admitted. I’ve worked with high vacuum systems and realize what equipment would be needed but neglected to account for the volume of water.

You really need a cold trap to keep all the water vapor from going through your pump. The diy version seems to a second vacuum chamber in a dry ice bath. Basically you need the trap to be enough colder than the chamber to condense the vapor. Vacuum pumps are expensive. Maybe you could get a cheap one you didn’t really care about that didn’t pull a great vacuum and you could skip the trap but seems to be pretty important. Maybe you could get a bunch of desiccant it might help. To dry the the pumping system.

Basically messing with dry ice in the quantity needed to make any appreciable amount of food would be a non starter for me.

If I was to go down this path it would be for quantity not novelty. Getting the process down for max output probably requires temp control in the chamber warmer the temps the faster it dries.

My take is I don’t see how you could diy a decent system for less than 1k$.

By the time your in that deep the commercial system seems more appealing. Just to save R and D time

 

[Ashful]

I'd think you'd want to keep the freezer small, if the goal is to get anywhere near 14 psi vacuum. Given the wall construction of most modern freezers, even a modest pressure might be enough to buckle it, on a larger side panel. Just a 6"x6" square in the center of the panel will see 500 lbf., which I have to imagine is sufficient to cave the side of a kitchen-sized refrigerator, if not even a collegiate.

Do note it's an exponential (at least cubic) problem, as the larger panel supported only at 3 edges is both weaker, and also sees larger forces.

 

[EbS-P]

I'd think you'd want to keep the freezer small, if the goal is to get anywhere near 14 psi vacuum. Given the wall construction of most modern freezers, even a modest pressure might be enough to buckle it, on a larger side panel. Just a 6"x6" square in the center of the panel will see 500 lbf., which I have to imagine is sufficient to cave the side of a kitchen-sized refrigerator, if not even a collegiate.

Do note it's an exponential (at least cubic) problem, as the larger panel supported only at 3 edges is both weaker, and also sees larger forces.

One Would need a vacuum chamber inside. Available with lid.

 

[stoveliker]

The inside plastic of the freezer will certainly buckle and start leaking in at the edges (if not cracking).

You can safely run water vapor through even oil-sealed pumps. Membrane pumps can be nicer (though the membrane replacement is harder than replacing the oil). As long as the oil pump works hard enough the oil is warm enough to exhaust the water from the oil down to equilibrium concentration.

(At the institute I did my PhD we had a 4 story high demo of a vacuum gauge. 4" dia glass tubes, water, oil pump. I never understood why they did this because the water kept boiling...)

 

[begreen]

$4k to $6k. I love Astronaut ice cream as much as the next guy, but... damn!

j/k... I know you prep'ers have loftier goals than my bricks of Neopolitan.

The medium size is $2895. Not so different from a wood stove, it's a lifetime investment. Over the course of say 10 yrs, that's less than $300 a year. Given today's grocery bills, not a bad investment, especially with the extensive gardens and greenhouse production that Dan has. It helps them achieve a notably higher quality diet free from the crap and contamination in processed food. Organic produce is not cheap.

Harvest Right™ | Home Freeze Dryers | Freeze Dried Food Storage Home Freeze Dryers

harvestright.com

 

[EbS-P]

The medium size is $2895. Not so different from a wood stove, it's a lifetime investment. Over the course of say 10 yrs, that's less than $300 a year. Given today's grocery bills, not a bad investment, especially with the extensive gardens and greenhouse production that Dan has. It helps them achieve a notably higher quality diet free from the crap and contamination in processed food. Organic produce is not cheap.

Harvest Right™ | Home Freeze Dryers | Freeze Dried Food Storage Home Freeze Dryers

harvestright.com

And think space ice cream at home! Only time I ever got it was when we visited the Cosmosphere