Now that I have the box fan dehydrator built, its time to dry something. And I just got a bucket full of basil from my farmer neighbor, at first I thought about making it into pesto and freezing it into ice cube trays. But why not put the box fan through its maiden voyage, to work out any kinks.
Well it turns out that the type of filter you use can be a major kink in using a box fan dehydrator. The filter that I started with was a cotton style filter with a MERV 8 rating. The problem with using a filter with that high of a rating was that the box fan wasn’t strong enough to blow its air capacity through the filter. So a majority of the air ended up bouncing off the filter back though the box fan. So what was supposed to take a day to dry out ended up taking five days. So for next time I’m going to use one of those blue furnace filters that has a MERV 2 rating, since a MERV 8 is just overkill in this application. That is unless you are a dust freak/germ-a-phobe, then maybe a MERV 8 is the way to go.
3 comments on “Drying Basil in the Box Fan Dehydrator”
You know, that was what killed me on AB’s design, was finding those damn cotton furnace filters. And when I actually did find them, I wasn’t about to spend $3-4 a pop for something that I was going to toss out after the drying was all done.
OK, so to answer your questions:
1) Yes the aluminum does hold up over time. And no I wouldn’t have chosen a different material. You basically have three different materials that you can go with: aluminum (bright or mate black) or fiberglass. For me, I didn’t even consider using fiberglass, since fiberglass screen seems to shed and splinter a bit too easily for my taste. Plus the last thing I want in my food, is fiberglass screen particles. So that left me with aluminum, the bright style. Since my reasoning was if I use a plan aluminum pot to cook my food, why would I want to dry my food on aluminum coated is some kind of unknown black finish.
I really haven’t had any sort of rusting problems from the steel staples that hold the mesh to the frame. And as far as clean-up goes, I just use dish soap, a sponge and sometimes a scrub brush to clean up the frame without any problems, and as soon as I’m done rinsing off the frames. I just stack them on the running box fan to dry out. One thing I have noticed, is that I stapled the mesh to the side of the frame instead of the bottom, so sometimes small food particles will get trapped in that gap at the bottom of the frame. But so far it was been relativity easy to shake out anything caught in that gap.
2) As far as an air filter, yes I think it’s necessary. Because no matter how clean your house it, there is still dust floating around. And since my house is about 90 years old, plus I run the drying operation in the basement (which is dusty as hell) I feel a little bit better trying to stop what I can in the way of dust getting onto the items being dried. Plus the filter acts as kind of a crude drip tray to catch any errant fluid or fine particles from the actual items you are drying. But with a furnace filter and the box fan on high, it most certainly gets the drying done in a hurry. (And yes I can see the irony in using a fiberglass furnace filter, but not using fiberglass screen material.)
It’s funny that you mention making beef jerky, since it’s crossed my mind a couple of times to give it a try on this set-up. I just always get wrapped up in some other project, and the idea just gets put on the shelf for another time.
But if you have anymore questions. Just let me know.
So, I’ve done AB’s box fan dehydrator a couple of times now and I can say that I’m disappointed in the price/reuseability of the air filters… even at the best deal, just three are pretty expensive.
So, my intention is to do exactly what you’ve done with wooden frames and some sort of mesh. I had a few questions though, in hopes of profiting from your experience with them:
-Does the aluminum hold up over time? Would you have chosen a different mesh if given the opportunity? (Rust problems, clean-ability?) I make jerky a lot, which is fairly damp to begin with…
-Do you really find the air filter to be necessary? I thought about putting one on the intake side prior to seeing your picture with one. I noted the comment on the filter grade. I can only imagine how quickly food will dry out with the all mighty power of a box fan ripping the moisture away from it unimpeded..
Any input would be appreciated!