5/16 into 3/16

[325abn]

So I have 5/16 laterals running into a mainline, the main line needs to be replaced, the laterals are in good shape.

I have good slope throughout my sugar bush.

If I take the current 5/16 laterals, reduce them into 3/16 tubing and run that tubing down slope to a tank will the run of 3/16 pull a vacuum in the 5/16 part of the run?

Thoughts?

[VT_K9]

No experience with 3/16", but I think it would be safe to say the vac gains would not be there until the 3/16" was filled and helping pull. My concerns would be the length of 3/16" you are thinking and slope. From what I read it is a combination of slope and length which are factors in the vac production for 3/16". If loss was minimal at best and you are looking at transitioning to 3/16" the loss may be worth the risk. If no loss beyond a few feet and a reducing coupling then do it.

If I had a steep area to tap and did not want to or could not run a vac I would be interested in trying 3/16" to see what it is all about. I just have too many other projects to experiment with 3/16".

[325abn]

Yeah I was thinking once the 3/16 fills up it would take some time to pull the vac on the 5/16, but once there it should hold that vac. Assuming a tight system.

I can have some long drops with the 3/16th portion of the run.

[1/325a.i.r.]

I have not logged in here since 2015, was clicking on forums today regarding 3/16 (we have approximately 50 taps on that, another 100 plus on 5/16) and thought I had actually posted a thread start by accident when I saw your username. When were you at Bragg? I was there at A Co. 1/325 from 2002 to July 2004 when I was abruptly levied to Korea after initial OIF one tour. We are going to repair one of our 3/16 runs today as a log had fallen on it and tore it apart. I patched up other one last week, after my wife purchased some semi rigid CDL tubing. The original 3/16 we ran is very flexible, almost as easy to stretch as a rubber band compared to the new stuff. Both of our lines had longer runs which were damaged by deadfall. The 5/16 line had some fall on it as well, just pulled it down. Cut the logs off, hiked line back up the tree some and it was good to go. We just had a warm spell here and some of the larger producers nearby have already tapped. Most of the smaller ones have waited and will be tapping in next weeks or so. We are getting stuff ready now, probably fall in line with the later group. Have a good season.

Chris Acompora

All the Way1

[DrTimPerkins]

If I take the current 5/16 laterals, reduce them into 3/16 tubing and run that tubing down slope to a tank will the run of 3/16 pull a vacuum in the 5/16 part of the run?

Your vacuum would likely not be as high as it would be on a pure 3/16" system. The 5/16" lines have a much larger internal diameter and thus a much higher internal volume. That means there is more air to evacuate from the system than there would be with 3/16" tubing. The real answer is...it depends. It would depend upon how many trees you have, the flow rate, how much 3/16" and how much 5/16" tubing, and how tight you keep the system.

Think of it this way. What would you get for vacuum if you had 3/16" tubing connected to a barrel at the top? You have to evacuate all that extra air from the system to build up your vacuum.

If you had only a little 5/16" and a good amount of 3/16" below that, it probably wouldn't matter much. But if you have a lot of 5/16" with just a little 3/16" below it, it would likely impact it a lot.

[325abn]

Hello Brother Falcon. We are everywhere. AATW!

I was 3/325 & 4/325 1983 - 1989. Spent a year in Vicenza.

[325abn]

I like the barrel analogy Dr. Tim.

I plan on adding some 3/16 this year anyway so I think I will experiment with a few existing laterals to see what happens.

[maple flats]

At Tim Wilmot's presentation at the VVS maple conference earlier this month, he stated that adding a section of 3/16 downstream from 5/16 laterals did not help anywhere near as much as going 3/16 all the way (and then only if you have good slope). He did however say it could help a little, again assuming the slope, and feet of drop.

[1/325a.i.r.]

For a comparison of 5/16 and 3/16, we installed two runs of 3/16 line, one with 27 taps, other with 30 taps, after initially running four lines of 5/16 with a total of approximately 110 taps on them. The 3/16 were running for a few days prior to 5/16 starting to run sap. On average 3/16 was 80 to almost 100 percent of the yield that the 5/16 was providing us. We are getting going to change the other runs eventually, but not until we purchase an evaporator that can handle that 3/16 production. This is second year we will have the 3/16 line so we will see if production stays same. Good luck.

[DrTimPerkins]

On average 3/16 was 80 to almost 100 percent of the yield that the 5/16 was providing us.

Assuming you mean "80 to almost 100 percent" MORE yield than the 5/16"?

[Daveg]

It depends. It would help immensely if you had a lot of drop AFTER then lowest tap in the system. Can you place your tank at a lower point to achieve that?