I don't see why not. The thing you'd want to do is to have some sort of system of marking in order to be able to dial-in the same level of vacuum repeatably.
As an aside, I visited a new bean-to-bar startup I've been working with and they built one of these and the results are extremely impressive. A couple of notes based on what I saw:
-) Make the entire front of the unit in plexiglass so you can see everything.
-) Use something (i.e., weatherstripping foam) to make sure that all seals are air tight. This includes the seal around the hole at the top where the nibs are introduced. Air leaks will reduce the vacuum and reduce the efficiency of the system.
-) Find some way to introduce the cracked nib and shell at a steady rate. If the flow of nib/shell is too high some amount of shell will be dragged down without having a chance to be drawn off.
-) Introduce some sort of "baffle" to scatter the nib and shell after it falls into the chute but ABOVE the vacuum draw.
-) Pre-classifying is one key to making this process really time-efficient.
-) If you are not pre-classifying, post-classifying (having the nib that falls through all the way fall through a screen to catch really large bits) also works.
-) You can also play with (as in reduce) the airflow gap to increase the amount of vacuum that's available. This will give you more "headroom" depending on the power of the shopvac you're using.
-) Consider using something like the Oneida Dust Deputy Cyclone to ensure that very small fines don't clog the filter of the shopvac, reducing its efficiency over time.
08/18/13 21:08:31 @donny-gagliardi:
Clay could a ball valve be used in place of the wood flap to control air flow?
With a pre-classifier system you can make the whole process much more efficient. You can make your own, but you might want to take a look at this set of sieves made for gold panning that fit on top of a 5-gallon bucket. The smallest sizes are way too small for winnowing (but may have other uses around the workshop) but the larger ones are perfect for pre-classifying. Individual sieves are also available - consider the 2 (1/2" - good for catching flats and uncracked beans), 4 , 8, and 12 mesh.
Donny -
I don't see why not. The thing you'd want to do is to have some sort of system of marking in order to be able to dial-in the same level of vacuum repeatably.
As an aside, I visited a new bean-to-bar startup I've been working with and they built one of these and the results are extremely impressive. A couple of notes based on what I saw:
-) Make the entire front of the unit in plexiglass so you can see everything.
-) Use something (i.e., weatherstripping foam) to make sure that all seals are air tight. This includes the seal around the hole at the top where the nibs are introduced. Air leaks will reduce the vacuum and reduce the efficiency of the system.
-) Find some way to introduce the cracked nib and shell at a steady rate. If the flow of nib/shell is too high some amount of shell will be dragged down without having a chance to be drawn off.
-) Introduce some sort of "baffle" to scatter the nib and shell after it falls into the chute but ABOVE the vacuum draw.
-) Pre-classifying is one key to making this process really time-efficient.
-) If you are not pre-classifying, post-classifying (having the nib that falls through all the way fall through a screen to catch really large bits) also works.
-) You can also play with (as in reduce) the airflow gap to increase the amount of vacuum that's available. This will give you more "headroom" depending on the power of the shopvac you're using.
-) Consider using something like the Oneida Dust Deputy Cyclone to ensure that very small fines don't clog the filter of the shopvac, reducing its efficiency over time.
Clay could a ball valve be used in place of the wood flap to control air flow?
With a pre-classifier system you can make the whole process much more efficient. You can make your own, but you might want to take a look at this set of sieves made for gold panning that fit on top of a 5-gallon bucket. The smallest sizes are way too small for winnowing (but may have other uses around the workshop) but the larger ones are perfect for pre-classifying. Individual sieves are also available - consider the 2 (1/2" - good for catching flats and uncracked beans), 4 , 8, and 12 mesh.
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