I made .54 gallons of walnut syrup from 10 taps and 35 gallons of sap. Brix ran about 1.5 compared to about 2.4 for my maples. Very interesting taste--like apple jelly. It was very difficult to filter. In fact, I wouldn't call it filtering. I tried to run it through a pre-filter and an orlon cone, but it wouldn't even get through the paper unless I squeezed it like a jelly bag. I think most went through the seams, so the syrup is very cloudy.
I would recommend using taps with very long shanks because of the thick and furrowed walnut bark. The cast aluminum Leader 5/16 spouts do not work well--the newer stainless steel spouts work much better.
I had visions of being a walnut producer, given that I have many more walnut trees here than maples (and prices I hear are being paid). But given the small production and the problems with filtering, I won't do it again. It was a fun experiment.
Central Ohio
Leader WSE 2x6
Old metal corn crib converted to "The Shack"
Smoky Lake 6 gallon water jacket canner
Daryl 5" filter press with air pump
Deer Run 125 RO
2023: 140 taps, buckets, 32 gallons
2019: 100 taps, buckets, 45 gallons
2018: 100 taps, buckets, 31 gallons
2017: 100 taps, buckets, 15 gallons
2015: 100 taps, buckets, 34 gallons
2014: 100 taps, buckets, 30 gallons
2013: 100 taps, buckets, 52 gallons