3/16 with mechanical vacuum

[Bolen Creek]

We currently have a system set up with a vac pump that pulls 25 in of vac. I was thinking about adding on to it using 3/16 and plugging them into existing line. I have decent drop. Just wondering if there is any negative to doing this and would I keep the same vac level as I would with normal system

[Cedar Eater]

I think you would increase the vacuum on the lowest trees on the 3/16" line. You might not increase much on the highest trees.

[BnSmaple]

I just installed a similar system 3/16 7-10 taps per lateral feeding into 1" mains hooked to a MES releaser and a indiana vacuum pump pulling 27.5" at the releaser. So far have collected 17 gal of sap per tap.

[maple flats]

I have a similar set up. In my woods with good slope I have a vacuum tied to a vacuum tank. As such I regulate it down to 19". Then about 1/3 of my taps are on a side hill with good slope. There I have 3/16 with 14-41 taps per lateral. I'm adding a vacuum gauge at the lower part of that largest tap count to see what I'm getting. I will likely split that into 2 laterals. All my other 3/16 have no more than 31 taps on a lateral and the drop varies from 50' at one end to the vacuum mainline and down to 20' at the other end of the hill. Both read max. vac at the top. I'm adding vac gauges at some of those lines at the bottom to determine if I have overloaded any. I think only that 41 is overloaded. But, the sap flows great in all my 3/16 lines. When it's flowing I often catch myself just standing and watching the flow. Even on the low end of the one with 41 I still have vacuum based on how the sap flows in the drops at the bottom, but it is likely not great there.
In my other woods, I have no slope and I ran an experiment there. At the end of one of my mains I have 3 lines I changed to 3/16 because the slope if is away from the main. The main there has 21-22" of vacuum. I tied 3 laterals in 3/16 to it, one with no slope and 2 with negative slope of 2-3'. Those also flow well, but I haven't added gauges there yet. I suspect the vac at best will show at 17-18". I'll get gauges on there this week. Those 3 laterals are not loaded like the other woods, one has 7 taps, one 8 taps, both negative slope and the level one has 7 taps. A gauge will go on all 3 at the end of the line.
Last year was my first using 3/16 but so far I'm very impressed. If the woods that has little to no slope does well on those 3 I'm trying, the woods my get all 3/16 as lines get renewed over the years. I'm not likely going to remove good laterals to change them so it will take a few years.

[WESTMAPLES]

last year i installed 4 runs of 3/16 with 7-12 pre run with 50 ft of drop into a 3/4 in main, with some flatter runs of 5/16 off the other side of the main with the thoughts of adding mech vac next year ( 2017) it worked good being just gravity . i setup the mech. vac releaser with a 60 gal vac tank supplied from 600 ft away from my other vac station yesterday it was working great , didn`t get to measure how much of a difference there is yet, but i can tell you all the vac gauges at the top of the 3/16 where maxed out after turning the releaser on , have to wait a few day to tell you the exact difference it makes, but it sure seemed worth the effort the hr i saw it working .