During my presentation this past Saturday at the North American Maple Syrup Council meeting in Wisconsin I introduced some new fittings that Wade Bosley and I (UVM PMRC) have developed and tested over the past few years and will be testing further over the 2024 maple season. While I can't go into it really deeply in a short post, there are three main things:
1. Barb-Spout. The barrel (nose) is considerably shorter than a regular maple spout to reduce the amount of outer edge wood/xylem tissue that is blocked off by standard spouts. Sap flow and sugar content is highest in the other rings of wood, so this spout is designed to allow better and faster access to sap flow in that area. In order to maintain stability due to the shorter barrel, the spout has a series of graduated barbs (much like a ring-shank nail). The first pair of barbs engages in the wood, the next pair in the bark, and the last two provide a positive stop so spouts are not overdriven. If using in thick-barked trees, the larger flakes of bark should be scraped off first. We’ve seen a 10-23% improvement in sap yield in our testing over 2 yrs.
2. Arc-Flow Fittings. These fittings have a curved design which is designed to reduce friction and turbulence in fitting junctions. The Arc-Flow design can be incorporated into spouts, tees, saddles, end-tees, etc. In modeling calculations, it provides a 5-10% improvement in sap yield. Note that unlike a normal tee, the post faces downward instead of outward (away from the tree). This is so it can be easily flipped over for tapping below the lateral line. Only one end-line fitting needs to be made with this design as it can be used on either the right or the left side of the tree. The other thing that’ll be done on all these fittings is to bevel the connection edges at a 45° to reduce turbulence and friction between the liquid and fitting when entering and exiting the fitting. I've posted several videos we've made during testing at: https://www.youtube.com/playlist?lis...kN7muW8AXvxphj to help show turbulence inside the various types of fittings, and why the Arc-Flow fittings are superior to standard fittings.
3. External Maple Tubing Fittings This fitting is designed to replace barbed fittings that go INSIDE of tubing with fittings that fasten EXTERNALLY. Thus there is no restriction to flow and no place for microbial masses to build up. These can be configured to spouts, saddles, unions, tees, etc. There is a small clip with a barb that goes on each leg to secure the tubing in place. The internal passage is slightly tapered to accommodate variations in tubing sizes and to snug up the tubing tightly into the fitting with a tubing tool so it will be vacuum tight. It is designed to help with the 3/16” tubing clogging issue, but could also be used for 5/16” tubing to reduce frictional losses in lateral lines.
Photos of these are at: https://photos.google.com/album/AF1Q...qsQTIwKaoehUeg (I hope that link works)
UVM has filed patent applications for each of these and for several embodiment (variations). We’ve been working with a company in Vermont to design and prototype these fittings since the designs require somewhat complicated injection molding tools to construct. This company (Middle Valley Maple) will do both direct mailing to producers as well as distribute via any maple equipment company who wishes to carry these fittings. Cost should be about the same as standard fittings. More information will be available after testing in the 2023 season.
We’ve ordered the test molds and hope to have some units produced shortly after the new year. They will be tested by researchers and Maple Extension folks as well as selected maple producers during the 2023 season.
I'll be presenting this information at the Lake Erie Maple Expo on Nov 11-12, 2022.