Hop Drying Oast design?

[lexuschris]

Heyas,

Hop harvest time is coming up and I'm trying to come up with a hop dryer, or 'oast', design. I have 40 plants, and I expect a fair amount of hops in this 2nd year of growth. Air drying is not really a great option, as Arizona summers can get real humid during the monsoon season (August).

Also, I need to make it collapsable & easily stored between seasons. I came up with one idea on this scetch, and would love some comments and or other suggestions. I'm not handy at all, so my approach feels very one-dimensional. Any help is appreciated.. especailly from those of you who build things for fun & profit!

Thanks,
-LexusChris

Oast_Design1.pdf

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[lexuschris]

Spent a bit of time reviewing posts on HomeBrewTalk.com and GVH_Dan has many good points. I can already see some good suggestions on the design.

+ Use a centifrugal fan, instead of a box fan to accomodate more air movement accross pressure drops
+ Mount fan under oast to pull air thru, rather than push. This reduces hop cone agitation & luplin shake-out.
+ It is difficult to pull a lot of air through so many layers. I might be better off with 2-3 shallow box designs, using smaller screens & cheap box fans. e.g. 3 oasts, 3' x 4' screens, 3 layers deep = 108 sq.ft drying area... ???
+ Too much heat can evaporate hop oils & also reduce alpha acids. Need to keep it warm (85-95-F) rather than hot....

--LexusChris

[backhousebrew]

Let me know when you're ready to start construction. I have all the tools to build it.

[Marotte Brewery]

Ever think of using A/C filters instead of screens? They stack very well and the creases in the filter would work perfect for keeping the hops separated. I saw Alton Brown use that setup for drying all sorts of foods, including fruits and even meats.

[backyard brewer]

Ever think of using A/C filters instead of screens? They stack very well and the creases in the filter would work perfect for keeping the hops separated. I saw Alton Brown use that setup for drying all sorts of foods, including fruits and even meats.

+1.

16x16 pleated filters duct taped together and stacked on the inlet side of a 16x16 box fan. The fan will draw the air through nicely and everything but the fan is cheap enough to be disposable so storage is really easy. There should be enough give in the filters not to crush the hops but if not you could make a plenum from a 16X16X?? tall box, drop a filter in, line it with hops, another filter, etc...

Basic fiberglass air filter from Grainger is $5.55 each, 12 to a case. http://www.grainger.com/Grainger/AIR-HA ... Pid=search



You could probably cut the fiberglass off if you were worried about the hops sticking to it since they have that screen on them.

[lexuschris]

I looked up the episode with Alton Brown taping the filters together and drying jerky with it. It looked like he had like 3 layers drying on the fan, and it worked well.

I wonder how many you could stack before there was too much for the fan to reach thru?

Also, with 40 plants worth to dry, I have a pretty large volume of hops ..and only over a short period while I am out there.. (2-days).

Last time, we used a large food dehydrator (at least as large as I could order online) and while great results, it was just too small for the volume we had. We ended up putting the rest on full size screen doors (2 of them) and letting them dry in the sun. We got lucky that no afternoon monsoon rains came up!

Maybe I should think more along the lines of 2 large screens taped together, sandwiching a large layer of hops, and just put a few box fans around them to move the air alot.... rather than trying to pull through a dense stack of them...??

Hmmm....
--LexusChris

[nico soze]

I looked up the episode with Alton Brown taping the filters together and drying jerky with it. It looked like he had like 3 layers drying on the fan, and it worked well.

I wonder how many you could stack before there was too much for the fan to reach thru?

Also, with 40 plants worth to dry, I have a pretty large volume of hops ..and only over a short period while I am out there.. (2-days).

Last time, we used a large food dehydrator (at least as large as I could order online) and while great results, it was just too small for the volume we had. We ended up putting the rest on full size screen doors (2 of them) and letting them dry in the sun. We got lucky that no afternoon monsoon rains came up!

Maybe I should think more along the lines of 2 large screens taped together, sandwiching a large layer of hops, and just put a few box fans around them to move the air alot.... rather than trying to pull through a dense stack of them...??

Hmmm....
--LexusChris

or you could just buy 3 more of those dehydrators....

[maltbarley]

I have some ideas, Chris. Let's talk at the next meeting. I think the biggest issue will be what size of flat material (MDF sheets) you can haul. Measure the back of an LX*** or whatever and we can draw up some plans.

The basic idea is a box with a light bulb at the bottom and a box fan on top pulling the heat up. Simple framed screens will hold the hops.

[lexuschris]

Sounds good!

Reminds me that I need to cement our location for this meeting. I'm hoping for a return to Out of the Park, but have yet to call Dan... Will let everyone know on the boards when its certain...

Thanks for the suggestions everyone! Always a fun learning experience!
--LexusChris