Extended 3/16" line

[Ptim]

I have 4 runs of 3/16" lines with 20-25 taps per line going into two barrels. I want to extend it 100' so I can run more lines into a tote. There is drop going another 100'. Should I just extend each line or could I tee into one 5/16" line to the tote?

[motowbrowne]

Just extend each line. You'll be certain to get the maximum vacuum that you can by doing so.

[n8hutch]

How much drop in that last 100 feet? If it's marginal I would go with 5/16 and keep it tight, 3/16 does not work well with marginal slope.

Its natural to assume that all that head or drop before it flattens out would keep that sap running but it doesn't. 3/16 without the proper slope is disappointing at best I've tried it.

[Cedar Eater]

You can do either, but for only 100' I would extend the 3/16 and capture the extra drop.

[Ptim]

It's probably another 5'-7' of drop

[BSD]

It's probably another 5'-7' of dropIMO, go with 3/16. gain a few more inches of vacuum

[Atgreene]

I was poised to ask the same question. I've got to go under a road through a 4' box culvert, down a slope, through another 4' culvert then into a mainline under vacuum. Was debating if having it hooked into vac made 3/16 or 5/16 work better, probably 12' drop in 300'.

[GV2]

3/16 without the proper slope is disappointing at best I've tried it.

I second that. I tried a 25 foot drop in elevation from the last tree over 600 feet (i.e 4% slope) and I was very disappointed. Granted it is sloping down a north side and we only had on average 48 hour thaws this season so I am suspecting ice in the line may be the limiting factor. I have 23 trees zigzagged on about 1 to 2% slope feeding in. Looks like it will be above freezing all next week. If it still under performs I am going to try and work a mainline in next year. Just curious, what do you consider "proper slope" for a) the 3/16 tapped section (e.g. zigzag section) and b) the 3/16 elevation drop to gain pressure?

[motowbrowne]

I second that. I tried a 25 foot drop in elevation from the last tree over 600 feet (i.e 4% slope) and I was very disappointed. Granted it is sloping down a north side and we only had on average 48 hour thaws this season so I am suspecting ice in the line may be the limiting factor. I have 23 trees zigzagged on about 1 to 2% slope feeding in. Looks like it will be above freezing all next week. If it still under performs I am going to try and work a mainline in next year. Just curious, what do you consider "proper slope" for a) the 3/16 tapped section (e.g. zigzag section) and b) the 3/16 elevation drop to gain pressure?

Did you walk that line and check for leaks or blockages?

[GV2]

Did you walk that line and check for leaks or blockages?

Seeing how I only have this one line and buckets, I do walk the line just about every evening. I did repair a block early on but when there are bubbles to watch everything appears to be in order, though I did read today about bubble behavior on lower trees if a line is overloaded and it sounded familiar. I will check for that possibility too. I was just curious as to what 3/16 folks consider inadequate slope because others have said slope does not matter if you have the pressure/elevation drop.

[BSD]

Seeing how I only have this one line and buckets, I do walk the line just about every evening. I did repair a block early on but when there are bubbles to watch everything appears to be in order, though I did read today about bubble behavior on lower trees if a line is overloaded and it sounded familiar. I will check for that possibility too. I was just curious as to what 3/16 folks consider inadequate slope because others have said slope does not matter if you have the pressure/elevation drop.do you have a vac gauge? that will help ID potential problems

[GV2]

do you have a vac gauge? that will help ID potential problems

I did buy one but did not install it because most evenings there is nothing moving in the line, which is why I am curious if the 4% north slope in my drop could be the limiting factor. I know it is hard for folks to diagnose without seeing the setup but I appreciate the feedback.

[BSD]

is the line full? or sparse and lots of bubbles?

[GV2]

is the line full? or sparse and lots of bubbles?

Boy that is a good question! I am not experienced enough yet to tell just by line weight. last night I did see stationary bubble "sections" about 10 feet apart and more. No sign of bubbles in the 600 foot drop section. My guess would be "full".

[n8hutch]

I second that. I tried a 25 foot drop in elevation from the last tree over 600 feet (i.e 4% slope) and I was very disappointed. Granted it is sloping down a north side and we only had on average 48 hour thaws this season so I am suspecting ice in the line may be the limiting factor. I have 23 trees zigzagged on about 1 to 2% slope feeding in. Looks like it will be above freezing all next week. If it still under performs I am going to try and work a mainline in next year. Just curious, what do you consider "proper slope" for a) the 3/16 tapped section (e.g. zigzag section) and b) the 3/16 elevation drop to gain pressure?

I'm not expert but I personally won't set up any more 3/16 tubing unless I have 8 to 10 % or 8-10' every 100 of slope after my last tap, the zigzag portions of the run are not as critical you could probably get away with almost level in short distances, but the end run / after the last tap needs to be fairly steeply pitched in my opinion.

I tried some lines with 3-5% slope and found that they were not as productive as when they where bucket trees in the past.

If you have 4% slope you would need to run 700 to 800 feet after the last tap to get the desired elevation drop, that's alot of tubing . You might have 3 rolls up to get 25 taps. Doesn't add up for me, your mileage may vary.

[GV2]

Thanks Hutch. before this year's setup I did ask about slope on this forum and got a few "slope does not matter" responses, but I am tending to agree with your first hand knowledge. I would be curious to hear if 4% works for other. I did run a 3/16 line on good slope in 2015 but did not like the sap % and collection location. Next year I think I am either going to go back to it or turn this year's mostly rock maple (failed) stand in to a mainline / 3/16 low-tree-count laterals hybrid. PS: sorry for high jacking the thread!

[Cedar Eater]

My 3/16 natural vacuum lines are nearly level on a plateau and then drop off down a 15% slope for a 30' change in elevation. On several of those, I pick up a tree or two on the way down the slope. I'm very satisfied with them. These are reds and I'm certain that I far exceed what I would get from them with buckets. I also have one 3/16 line with 27 taps that is nearly level and is over 700' long but has a small cheap 12VDC diaphragm pump providing 24" of vacuum. I think that line is overloaded. Next year I will split that into two lines that join at the pump.