How many taps on 5/16" for natural vacuum

[danfredw]

I've been a bucket guy but my neighbor got us into 3/16 natural vacuum last year. It's not a huge slope but it worked. From what I understand and have read, somewhere between 20-25 taps is optimal to get enough flow but also not overwhelm the possible flow.

This year he wanted to run multiple 3/16 lines to 1 5/16 line. Does the logic still apply? If 25 taps are ok on 3/16, how many total will work to create the same natural vacuum on 5/16? Anyways he did it, one 5/16 maybe 100' line with 4 3/16 lines teeing into it, maybe 80 taps.

I've found one thread saying that the 5/16 may not hold the sap. For us it is, so maybe that means our slope is so bad it's not doing much. I've thought about putting some vacuum gauges in but FW Webb is far from my house. Lots of variables but I thought it would be interesting.

In the great runs this weekend we gathered maybe 80 gallons. I had 25 drops on buckets last year and feel like I would have gathered the same. Except he also had 50-75 taps on separate 3/16 lines and we gathered a ton. So compared to what I normally get, it's about the same, but combined we aren't doing super.

Ideally we're building a sugar shack next year and/or going to some vacuum, so this may all be moot, but can I convince him to abandon this 3/16 to 5/16 idea? I'm on 2 acres, he's got 56. So I'm never going to get bigger myself but I can be frustrated with decisions he makes. I would guess 10-15 acres of those are maples and we're just tapping one hedgerow between corn fields.

[ADK_XJ]

I've been a bucket guy but my neighbor got us into 3/16 natural vacuum last year. It's not a huge slope but it worked. From what I understand and have read, somewhere between 20-25 taps is optimal to get enough flow but also not overwhelm the possible flow.

This year he wanted to run multiple 3/16 lines to 1 5/16 line. Does the logic still apply? If 25 taps are ok on 3/16, how many total will work to create the same natural vacuum on 5/16? Anyways he did it, one 5/16 maybe 100' line with 4 3/16 lines teeing into it, maybe 80 taps.

I've found one thread saying that the 5/16 may not hold the sap. For us it is, so maybe that means our slope is so bad it's not doing much. I've thought about putting some vacuum gauges in but FW Webb is far from my house. Lots of variables but I thought it would be interesting.

In the great runs this weekend we gathered maybe 80 gallons. I had 25 drops on buckets last year and feel like I would have gathered the same. Except he also had 50-75 taps on separate 3/16 lines and we gathered a ton. So compared to what I normally get, it's about the same, but combined we aren't doing super.

Ideally we're building a sugar shack next year and/or going to some vacuum, so this may all be moot, but can I convince him to abandon this 3/16 to 5/16 idea? I'm on 2 acres, he's got 56. So I'm never going to get bigger myself but I can be frustrated with decisions he makes. I would guess 10-15 acres of those are maples and we're just tapping one hedgerow between corn fields.

I am only beginning my own experiments with tubing but, from what I've read and briefly witnessed, 5/16 is simply too much diameter to create the same kind of sap "column" that you would get with 3/16 that creates that head pressure and ultimately the natural vacuum.

I see this play out on the lines I've put in on the sloped section(s) our new property: the 3/16 line has a solid, speedy run of sap with intermittent air bubbles, while the 5/16 line has just equal ratio of air to liquid or less moving much slower.

[Z/MAN]

I am only beginning my own experiments with tubing but, from what I've read and briefly witnessed, 5/16 is simply too much diameter to create the same kind of sap "column" that you would get with 3/16 that creates that head pressure and ultimately the natural vacuum.

I see this play out on the lines I've put in on the sloped section(s) our new property: the 3/16 line has a solid, speedy run of sap with intermittent air bubbles, while the 5/16 line has just equal ratio of air to liquid or less moving much slower.

I know everyone says you don't get natural vacuum on 5/16 tubing. I have twenty taps on 5/16, very steep drop towards the top and levels off at the bottom. (Not ideal)I usually pull 5-6 inches of vacuum and at times as high as 9 inches. Normal vacuum bubbles in the line and I can even find leaks by the extra bubbles at the leak. YES, you can get natural vacuum with 5/16! I realize my vacuum at the top is probably better than the bottom.

[DrTimPerkins]

You can get decent natural vacuum on 5/16" lines, but it is much slower to develop and much more difficult to maintain. It'll work good when the sap is flowing well, but not well at all at low flows (not enough sap to generate vacuum) or at peak flows (too much sap causing backpressure). The drawbacks are big enough that people typically don't try.

[danfredw]

You can get decent natural vacuum on 5/16" lines, but it is much slower to develop and much more difficult to maintain. It'll work good when the sap is flowing well, but not well at all at low flows (not enough sap to generate vacuum) or at peak flows (too much sap causing backpressure). The drawbacks are big enough that people typically don't try.

Thanks for the replies. I'm wondering what my action item is then. Yes, our setup doesn't really work, but do you have any suggestions on what we should do instead without a vacuum pump? I'm really guessing here as I have a lot to learn, but run a 3/4 or 1" main line that each 3/16 natural vacuum line tees into, and then that main line will drain with natural gravity to our tote? The sure solution I know would be to run for 3/16 lines to our tote, but that becomes a lot of tubing.

Assuming we do get a vacuum pump for next year, would the mainline be the best setup to prepare for it too? Or for any other future year?

[motowbrowne]

Thanks for the replies. I'm wondering what my action item is then. Yes, our setup doesn't really work, but do you have any suggestions on what we should do instead without a vacuum pump? I'm really guessing here as I have a lot to learn, but run a 3/4 or 1" main line that each 3/16 natural vacuum line tees into, and then that main line will drain with natural gravity to our tote? The sure solution I know would be to run for 3/16 lines to our tote, but that becomes a lot of tubing.

Assuming we do get a vacuum pump for next year, would the mainline be the best setup to prepare for it too? Or for any other future year?

A few options. Running the 3/16 right to the tote is probably the cheapest and easiest. Assuming it's not hundreds and hundreds of feet. Adding a mainline costs a fair amount and requires a kinda involved installation.

You can add a cheap shurflo vacuum pump to the mess of 3/16 laterals also very cheaply. I had great success for five years doing this.

Adding a mainline is something you'll really want to do if you ever decide to use real vacuum pump and a releaser and use 5/16 to get the best sap yields and not deal with clogging 3/16 fittings. I just took the leap from 3/16 and shurflo to a setup like I just described. For me at 330 taps and selling all retail, it made sense, but I think the usual tipping point would be between 500-1000 taps before it makes sense to run that stuff.

If you want to chat about simple diy vacuum stuff, I'd be happy to chat on the phone sometime. 715-222-3237

You should be warned though, you start running a bunch of 3/16 lines and shurflo pumps, you'll be swimming in sap pretty soon and you'll end up shopping for an RO and a bigger cooker.

[Sugar Bear]

I know everyone says you don't get natural vacuum on 5/16 tubing. I have twenty taps on 5/16, very steep drop towards the top and levels off at the bottom. (Not ideal)I usually pull 5-6 inches of vacuum and at times as high as 9 inches. Normal vacuum bubbles in the line and I can even find leaks by the extra bubbles at the leak. YES, you can get natural vacuum with 5/16! I realize my vacuum at the top is probably better than the bottom.

I know everyone says things, but I can never get my head around how much of it is just inconsistent with my experience.

I have a 5/16 inch run with 8 sugar taps on it this year. Last year it had only 7 taps on it. It is a straight run and a straight final run of about 75 feet that drops 12 to 15 feet in that 75 feet to the collection barrel. Last year the gauge at the top of the run peaked at 17 inches of mercury and ran well into the freeze of the nights. This year it has only gotten to 10 inches ( the most recent run ) so far with 1 more tap added at the top. But the fat lady is still in bed. At least for now. But I am suspicious I added a micro leak on T fittings this year.

So for me 5/16 generates vacuum for sure. But its tricky and very demanding of the proper landscape 4 SURE! I have another sugar run with 10 taps on it and a steeper final run but much shorter at a distance of only about 35 feet to the collection barrel and drops about 10 feet. It does not do as well. It is also not a straight run, but the final run to the barrel is straight down the fall line of the hill, but only 35 feet in length and 10 feet in drop.

I should add here that the trees on these runs are a magnitude 10 on the maple tree Richter scale.

It should also be said here that it is far easier to set up a run of 5/16 taps on tubing that does worse then those taps would if they were on drops to individual buckets, then it is to do better. This is the main disadvantage.

[DrTimPerkins]

So for me 5/16 generates vacuum for sure.

No doubt 5/16" tubing can generate vacuum, but just more difficult to have it work well and consistently. 5/16" tubing left open at the bottom will eventually drain and vacuum will be lost...3/16" tends not to drain (as completely at least), so vacuum is easier to start and maintain. The inner volume also makes it easier to develop vacuum in 3/16" tubing. Kind of the opposite of sucking the air out of a container...if you have a small container (3/16") it is fairly easy. If you have a large container (5/16" tubing), it takes a lot more effort to suck all the air out.

[Sugar Bear]

No doubt 5/16" tubing can generate vacuum, but just more difficult to have it work well and consistently. 5/16" tubing left open at the bottom will eventually drain and vacuum will be lost...3/16" tends not to drain (as completely at least), so vacuum is easier to start and maintain. The inner volume also makes it easier to develop vacuum in 3/16" tubing. Kind of the opposite of sucking the air out of a container...if you have a small container (3/16") it is fairly easy. If you have a large container (5/16" tubing), it takes a lot more effort to suck all the air out.

Yes, with my experience I can get my head around what you say here. Even though I have never used 3/16 but can see it through as "powering up" more easily and "powering down" less easily. Baby physics in concept to my baby physics mind.

I will add that last year was the first year I measured vacuum on my 5/16 line thatgenerated 17" on it and had been using that line with the seven taps on it for 4 years prior to that. It still drops as much sap per season now as it did in year 1. I do clean it well at EOS.

While I take the word of several in sugaring as the word of god, Tim Perkins included, Bruce Bascom told me that he was steering away from the use of 3/16 for the reason of clogging problems. My feeling is that if I used 3/16 I might have a much more difficult time keeping it clean and clog free over years. And of course there is the "tare it down ... throw it away ... and buy a new one concept" and that works well for many too.

But we need more of that concept like we need three more wars on three more continents right about now.

So I like the idea of learning and using where I can be effective with 5/16 natural vacuum and using it there and going to other options where I can't. On some reds this year I went with 5/16 lines and a solar powered pump and I have been overflowing by collection barrel on it. Rats!